Orthopaedica Belgica Musculoskeletal Trauma and Degenerative Diseases Research and Innovation in Orthopaedics 22 - 24 April 2015 Aula Magna, Louvain-La-Neuve Programme & Abstracts

With the participation of Belgian Association of Pediatric Orthopaedics (BAPO) Belgian Foot and Ankle Society (BFAS) Belgian Hand Group (BHG) Computer Assisted Orthopaedic Surgery (CAOS) Spine Society of (SSBe)

www.OB2015.org Table of Contents

DEPUY SYNTHES COMPANIES OF JOHNSON & Committees and International Faculty 4 JOHNSON IS THE LARGEST, MOST COMPREHENSIVE Welcome Address 5 ORTHOPAEDIC AND NEUROLOGICAL BUSINESS IN THE WORLD, BUILT UPON THE STRONG LEGACIES Scientific Programme

OF TWO GREAT COMPANIES. Wednesday, 22 April 6

www.depuysynthes.com Thursday, 23 April 10

Friday, 24 April 16

Abstracts of Invited Lectures 19

Abstracts of the Residents Session 109

Exhibitors 115

General Information

Registration 120

Social Programme 121

General Information 122

www.ob2015.org 3

Deckblatt_Kongress.indd 1 13.04.15 16:19 Committees and International Faculty Welcome Address

Congress President C. Delloye (President SORBCOT) Dear Colleagues,

Congress Vice-President J. Somville (President BVOT) We are proud to welcome you to the Orthopaedica Belgica 2015 Congress, taking place in Louvain-La-Neuve from 22 to 24 April 2015.

Scientific Committee Louvain-La-Neuve – a young university town – is happy to host the Orthopaedica Belgica 2015 Congress. X. Banse () W. Kurt (Liège) O. Barbier (Brussels) E. Munting (Ottignies-LLN) The plenary sessions will cover two main themes: the shoulder & research and J. Bellemans (Genk) L. Paul (Brussels) innovation in orthopaedic surgery and traumatology.

O. Cartiaux (Brussels) E. Pire (Liège) Orthopaedica Belgica 2015 also welcomes societies dealing with orthopaedic O. Cornu (Brussels) L. Renson (St-Truiden) subspecialities such as the Belgian Association of Pediatric Orthopaedics J. de Halleux (Brussels) F. Schuind (Brussels) (BAPO), the Belgian Foot and Ankle Society (BFAS), the Belgian Hand Group (BHG), and the Spine Society of Belgium (SSBe). S. de Wouters (Brussels) T. Thungen (Brussels) P.L. Docquier (Brussels) B. Vande Berg (Brussels) Furthermore the first Belgian CAOS (Computer-Assisted Orthopaedic Surgery) L. Fabeck (Brussels) T. Van Isacker (Brugge) Symposium will take place on Thursday, 23 April. The theme of the CAOS Symposium is ‘Improving accuracy in computer assisted orthopaedic surgery’. P. Gillet (Liège) O. Verborgt (Antwerpen) A. Hebrant (Brussels) S. Willems (Liège) We wish you an instructive Congress at the Aula Magna. N. Hollevoet (Gent) D. Zorman (La Louvière)

Yours faithfully, International Faculty Christian Delloye Johan Somville M. Bandi (Switzerland) J. Kieffer (Luxemburg) President Vice-President E. Baulot (France) P. Merloz (France) P. Boileau (France) L. Miladi (France) E. Camus (France) A. Petersik (Germany) F. Gouin (France) M. Richter (Germany) M. Guelfi (Italy) J. Verhaar (The Netherlands) G. Herzberg (France) A. Viladot (Spain) M. Hessmann (Germany) A. Witteveen (The Netherlands) A. Kamali (United Kingdom)

4 Orthopaedica Belgica 2015 www.ob2015.org 5 Wednesday, 22 April 2015 Concurrent Session Concurrent Session Wednesday, 22 April 2015

Belgian Hand Group Room Hocaille Belgian Hand Group Room Hocaille Innovation and research in hand surgery - Part I Innovation and research in hand surgery - Part II Moderators: Guillaume Herzberg, Lyon, France and Moderators: Bernard Lefebvre, and Jean Goubau, Brugge/Brussels Jeroen Vanhaecke,

14.00 I1 Semi-constrained DRUJ arthroplasty 16.25 I8 Robotic high definition imaging during wrist surgery Ilse Degreef, Olivier Barbier, Brussels

14.10 I2 Total wrist arthroplasty 16.35 3D reconstruction for malunion of the distal radius Guillaume Herzberg, Lyon, France Filip Stockmans, Kortrijk

14.40 I3 Total trapezometacarpal joint replacement - Are new designs better? 16.50 3D reconstruction for malunion of the forearm Nadine Hollevoet, Gent Frederik Verstreken, Antwerpen

14.50 I4 PIP arthroplasty with the Tactys prosthesis 17.05 I9 Nerve repair with neurotubes Jean Goubau, Brugge/Brussels Anne Lejeune, Brussels

15.00 I5 Scapholunate instability - Treatment with volar or dorsal capsular repair 17.15 I10 Anatomy and biomechanics of the TMC Joint - In vitro and in vivo Luc Van Overstraeten, studies Priscilla D’Agostino, Kortrijk 15.10 I6 New techniques in wrist arthroscopy Luc Van Overstraeten, Tournai 17.25 I11 Clinical applications of biomechanical research in elbow / wrist / hand surgery 15.20 I7 Arthroscopic testing of extrinsic ligaments of the wrist Frédéric Schuind, Brussels and Fabian Moungondo, Brussels Emmanuel Camus, Maubeuge, France 17.35 Discussion 15.30 Discussion

15.45 Coffee Break

6 Orthopaedica Belgica 2015 www.ob2015.org 7 Wednesday, 22 April 2015 Concurrent Session Concurrent Session Wednesday, 22 April 2015

Belgian Foot and Ankle Society Foyer Royal Belgian Foot and Ankle Society Foyer Royal Pes plano valgus Acquired pes plano valgus Understanding how and why Moderators: Antonio Viladot, Barcelona, Spain and Moderators: Marco Guelfi, Genova, Italy and Martinus Richter, Schwarzenbruch, Germany Angelique Witteveen, Nijmegen, The Netherlands Posttraumatic 14.00 I12 Anatomical and biomechanical aspects in the flatfoot Greta Dereymaeker, Leuven 16.55 I18 Etiology and treatment of posttraumatic pes plano valgus Kris Buedts, Antwerpen 14.15 Hindfoot deformity, clinic and radiology Pierre Maldague, Brussels Tibialis posterior dysfunction

14.30 I13 Novel hindfoot alignment measurements: Spatial insights in 3 D 17.10 I19 Recent insights in anatomy, pathology and classification weight bearing CT Marco Guelfi, Genova, Italy Arne Burssens, Gent 17.20 I20 My best therapeutic choice in stages I and II 14.40 I14 Influence of the gastrocnemius contracture in the genesis of a Martinus Richter, Schwarzenbruch, Germany flatfoot Angelique Witteveen, Nijmegen, The Netherlands 17.35 I21 Deltoid-spring ligament complex repair in acquired flat foot deformity 14.55 Discussion Stefan Desmyter, Gent

17.45 I22 Double calcaneal osteotomy: How far can we go? Congenital pes plano valgus Geoffroy Vandeputte, Lier Moderators: Anny Steenwerckx, Hasselt and Jacques de Halleux, Brussels 17.55 I23 My best therapeutic choice in stage III: Triple arthrodesis and his principles 15.10 I15 Flexible and rigid flatfoot in children: Etiology, clinic and treatment Thibaut Leemrijse, Brussels Pierre-Louis Docquier, Brussels 18.10 I24 My best therapeutic choice in stage IV 15.35 I16 Which Indications for subtalar arthrorisis in children and adults Bernhard Devos Bevernage, Brussels Antonio Viladot, Barcelona, Spain 18.25 Discussion and Conclusion 16.00 I17 Arthrorisis with calcaneostop screw in children corrects Talo-1st Metatarsal-Index (TMT-Index) Martinus Richter, Schwarzenbruch, Germany

16.10 Discussion

16.25 Coffee Break

8 Orthopaedica Belgica 2015 www.ob2015.org 9 Thursday, 23 April 2015 Concurrent Session Concurrent Session Thursday, 23 April 2015

08.25 Introduction Foyer Royal Belgian Association for Paediatric Orthopaedics Room Hocaille Christian Delloye, President of SORBCOT The paediatric spine Moderators: Frank Plasschaert, Gent and Instructional Course Renaud Rossillon, Ottignies

08.30 History of Mr. Pinocchio, MD, specialist in back diseases 09.15 I32 3D-deformity in scoliosis and supply of EOS Everard Munting, Ottignies - Louvain-la-Neuve Tamas Illés, Brussels

09.30 I33 Safety of sublaminar bands in idopathic scoliosis Pierre Moens, Leuven CAOS Belgium, a subsidiary of CAOS International Foyer Royal Improving Accuracy in Orthopaedic Surgery 09.45 I34 Cervical spine trauma: Radiological pitfalls…. Moderators: Bernardo Innocenti, Brussels and Nanni Allington, Liège Emmanuel Thienpont, Brussels

10.00 I35 Our experience in growing rods 09.15 I25 Introduction Lotfi Miladi, Paris, France Olivier Cartiaux, Brussels

10.30 Coffee break offered by Sprofit 09.20 Navigation I26 What does the surgeon want? Jan Victor, Gent 11.00 I36 Effects of physical therapy on postural parameters in adolescents What can the engineer offer? Luc Labey, Leuven suffering from idiopathic scoliosis: A prospective study Sirine Kachouri, Brussels 09.40 PMI I27 What does the surgeon want? Raf De Vloo, Brasschaat 11.15 I37 Conservative treatment of scoliosis (brace and physiotherapy): What can the engineer offer? Jos Vander Sloten, Leuven What is evidence based? Philippe Mahaudens, Brussels 10.00 Robotics I28 What does the surgeon want? Bart Stuyts, Antwerpen 11.30 I38 Internal fixation with occipital hooks construct for occipito-cervical I29 What can the engineer offer? Ramazan Ünal, Brussels arthrodesis - Results in 14 young or small children Jean-Paul Dusabe, Brussels 10.20 Numerical modelling I30 What does the surgeon want? Thierry Scheerlinck, Brussels 11.45 I39 Surgical treatment of cervico-thoracic Pott disease by kyphosis What can the engineer offer?Bernardo Innocenti, Brussels correction and circumferential fusion in a 2 year 9 month old child Jerry Kieffer, Luxembourg, Luxemburg 10.40 New technologies What does the surgeon want? Emmanuel Thienpont, Brussels What can the engineer offer?Benoît Herman, Louvain-la-Neuve 12.00 Discussion and Conclusions

Coffee break offered by Sprofit 11.00 11.30 Audience discussion ‘CAOS in Belgium’ I31 Experience in creating CAOS in France: Philippe Merloz, Grenoble, France

12.15 Proposal ‘CAOS Belgium, a subsidiary of CAOS-International’

10 Orthopaedica Belgica 2015 www.ob2015.org 11 Thursday, 23 April 2015 Concurrent Session Concurrent Session Thursday, 23 April 2015

The Shoulder: Recurrent traumatic anterior dislocation Aula Magna Residents Session Aula Magna What to do? Moderators: Christian Delloye, SORBCOT and Moderators: Etienne Lejeune, and Johan Somville, BVOT Bart Berghs, Brugge 11.30 O1 Comparison of intervertebral distances based on vertebral 09.15 Welcome vectors in normal subjects and in idiopathic scoliosis: is it an Christian Delloye, President of SORBCOT effect of the spinal cord protection? Harkirat Bhogal, Brussels 09.20 I40 How can I recognize a formerly anterior dislocation of the shoulder? Bruno Vande Berg, Brussels 11.40 O2 Impact of cement mantle thickness on local and systemic gentamicin concentrations in total hip arthroplasty 09.35 I41 When is an open anterior shoulder stabilization procedure indicated? Willem Van IJperen, Brussels Olivier Verborgt, Antwerpen 11.50 O3 Description of the vertebral spine curvatures relations using the 09.50 I42 Decision-making in chronic anterior shoulder instability: top view approach Bone or soft tissue procedure? Sagi Martinov, Brussels Pascal Boileau, Nice, France 12.00 O4 Reliability of patient-specific guides in total knee arthroplasty 10.05 I43 How I perform a Bankart arthroscopic procedure? Marie-Ange Ngo Yamben, La Louvière Jean-Emile Dubuc, Brussels 12.10 Presentation of the SORBCOT grants 10.20 I44 How I perform a bone block arthroscopic procedure? Olivier Cornu, SORBCOT Tom Van Isacker, Brugge 12.25 Announcement of the Winner of the Best Resident Paper Award 10.35 I45 A guided surgical approach and novel fixation method for an Christian Delloye, SORBCOT arthroscopic Latarjet Pascal Boileau, Nice, France 12.30 Lunch 10.50 Discussion

11.00 Coffee break offered by Sprofit

12 Orthopaedica Belgica 2015 www.ob2015.org 13 Thursday, 23 April 2015 Thursday, 23 April 2015

Plenary Session – The Shoulder: Reverse prosthesis Aula Magna Plenary Session – The Shoulder: Reverse prosthesis Aula Magna Updated data – Part I Updated data – Part II Moderators: Olivier Verborgt, Antwerpen and Moderators: Tom Van Isacker, Brugge and Florence Mulpas, Brussels Jean-Emile Dubuc, Brussels

14.00 I46 The story behind the reverse prosthesis: A tribute to Paul Grammont 16.00 I50 The ‘CLEER’ (Combined Loss of active Elevation and External Emmanuel Baulot, Dijon, France Rotation) patient: Do we have a clear answer? Pascal Boileau, Nice, France 14.15 How to convert an anatomical prosthesis into a reverse one? Pascal Boileau, Nice, France 16.15 Bone tumour at the shoulder: Which function afterwards? Two Belgian series 14.30 I47 Reverse prosthesis as a solution for displaced shoulder fracture I51 series: Lieven De Wilde, Gent in the elderly? I52 Brussels series: Thomas Schubert, Brussels Bart Berghs, Brugge 16.45 I53 Revising the reverse: The Nice experience 14.45 I48 Reverse and notching: Frequency? Threat? How to avoid this? Pascal Boileau, Nice, France Lieven De Wilde, Gent 17.00 I54 Tips and tricks in reverse arthroplasty revision 15.00 I49 How do I mobilize my patients after a reverse prosthesis? Florence Mulpas, Brussels Etienne Lejeune, Namur 17.15 Is an instable or an infected reverse prosthesis at the shoulder 15.15 Discussion salvageable? Philippe Debeer, Leuven 15.30 Coffee break offered by Orthophysics 17.30 Discussion and closing remarks Pascal Boileau, Nice, France

20.00 Gala Dinner at the ‘Château de la Hulpe’ (see page 121)

14 Orthopaedica Belgica 2015 www.ob2015.org 15 Friday, 24 April 2015 Friday, 24 April 2015

Introduction Aula Magna Can Research and Innovation in orthopaedic Aula Magna 08.25 surgery change our daily life? Christian Delloye, President of SORBCOT Computer-assisted surgery – Part II Moderators: Philippe Merloz, Grenoble, France and Instructional Course David Zorman, La Louvière

08.30 Can 3D Imaging in an operating theatre improve the results in 11.45 I58 Additive manufacturing: A new technology for manufacturing bone surgery? patient-specific instruments: History and practical examples Xavier Banse, Brussels Laurent Paul, Brussels

I59 Did guides change my practice? A French experience 09.00 Nursing Day organised by VOGV Room Hocaille 12.05 (Vereniging Orthopedisch en Gips Verpleegkundigen vzw) François Gouin, Nantes, France

12.20 I60 Did guides change my practice? A Belgian experience Can Research and Innovation in orthopaedic Aula Magna Pierre-Louis Docquier, Brussels surgery change our daily life? Computer-assisted surgery – Part I 12.35 Discussion Moderators: Luc Renson, Sint-Truiden and Olivier Cartiaux, Brussels 12.45 Lunch

Welcome 09.10 Research in orthopaedic surgery by industry and Aula Magna Christian Delloye, President of SORBCOT implant traceability Moderators: Alain Hebrant, Brussels and I55 Introduction and history of computer- assisted surgery 09.15 Johan Bellemans, Genk Philippe Merloz, Grenoble, France

Research by industry: What is for you a significant progress in the 09.45 I56 3D printing of ceramics-medical applications and 5 years last 5 years? retrospective follow-up in surgery Carsten Engel, Brussels 14.00 Introduction Alain Hebrant, Brussels 10.00 Guides for malunion: Applications Filip Stockmans, Kortrijk 14.05 I61 Product innovations in surgery as an outcome improvement for surgeons in the daily practice 10.15 Guides for prosthetic implants Martin Hessmann, Germany Emmanuel Thienpont, Brussels 14.25 I62 Advanced bearings in hips 10.30 I57 Guides and specific implants for complex acetabular defects Amir Kamali, UK Kris Govaers, Dendermonde 14.45 I63 Improved outcomes and efficiencies using population based design (SOMA) 10.45 What quality should be in CAOS? Significance for surgeons and for engineers Andreas Petersik, Germany Olivier Cartiaux, Brussels 15.05 Exploring knee biomechanics by robotic technology and computer Discussion simulation 11.00 Marc Bandi, Switzerland 11.15 Coffee break 15.25 Round table discussion 16 Orthopaedica Belgica 2015 www.ob2015.org 17 Friday, 24 April 2015

Research in orthopaedic surgery by industry and Aula Magna implant traceability Moderators: Alain Hebrant, Brussels and Johan Bellemans, Genk

Implant traceability

15.45 Introduction David Zorman, La Louvière

15.55 I64 The Dutch register: Lessons Jan Verhaar, Rotterdam, The Netherlands

16.15 I65 Implant registry in Belgium: Orthopride - where are we? Tine Willems, Gent

16.30 Discussion

16.45 Conclusions and Adjourn Christian Delloye, President of SORBCOT

16.50 Belgian Beer Reception

Abstracts of Invited Lectures

18 Orthopaedica Belgica 2015 I1 THE SCHEKER ARTHROPLASTY - PROMISING PRELIMINARY RESULTS I2 WRIST ARTHROPLASTY, TOTAL, INTERPOSITIONAL AND PARTIAL IN A SERIES OF 30 CASES G. Herzberg I. Degreef, L. De Smet Herriot , Claude Bernard University, Lyon, France Orthopaedic Dept., Hand Unit, Leuven University , Belgium Total Wrist Arthroplasty (TWA) for chronic advanced Wrist Destruction The Scheker prosthesis of the distal radioulnar joint is a semiconstrained joint The use of TWA to treat complete chronic destruction of the wrist joint is a arthroplasty, which allows full range of motion of the wrist, with a stable DRUJ joint controversial procedure. Orthopaedic Surgeons should keep in mind that total avoiding impingement between radius and distal ulna. Unsolvable degenerative wrist fusion (TWF) remains a gold standard. Total wrist arthroplasty is a challenger or posttraumatic problems of the DRUJ may be approached with the Scheker of TWF. It is more ambitious as patients always prefer motion but failures do arthroplasty to treat pain and instability and to regain a full range of motion with exist despite recent improvements. Only time and experience will provide more a stable DRUJ. We now have implanted the device in 30 patients over the last consistent prognosis factors when TWA is chosen for a particular patient. It 4 years at our centre. We conclude that preliminary follow-up is promising, but should be understood that TWA is unlikely to help the patient to gain motion. The that certain attention points need to be addressed at the time of surgery. Our aim of the procedure is to relieve pain and maintain functional wrist motion. A single centre experience with the DRUJ total joint arthroplasty supports that this procedure keeping about 30° of active wrist extension and significantly relieving technique appears to be a good solution in selected cases with unsolvable distal pain makes a difference when compared to total wrist fusion. radioulnar instability with loss of the DRUJ joint. The indication for TWA in rheumatoid wrist is painful pancarpal Rheumatoid arthritis in which total wrist fusion (TWF) would be the only alternative option. Volar carpal subluxation in Simmen-type 2 RA wrists should not be considered as a contra-indication. However the surgeon should not expect good results with TWA for Simmen type 1 or 3 RA wrists. The use of walking aids or the absence of functional wrist muscle-tendon units is also a contra-indication for TWA. Active infection is a classic contra-indication to any implant surgery. Arthroplasty surgery using new generation TWA designs has become a reliable procedure for most rheumatoid patients. The procedure is even more justified if the rheumatoid involvement is bilateral and if a total wrist fusion is chosen at the other side.

Total wrist destruction secondary to trauma or any non-rheumatoid wrist condition leading to severe wrist osteoarthritis with carpal collapse may also be an indication for TWA. However the vast majority of these potential candidates to TWA are still active males in their fifties. It should be obvious that these patients should not be selected for a TWA procedure since they will place too much mechanical stress on their wrist implant leading to an unacceptable risk of loosening. The ideal indication for TWA in a non-rheumatoid patient is a 70 year-old patient with severe pain from pancarpal osteoarthrosis secondary to old trauma.

Interpositional Wrist Arthroplasty for chronic advanced Wrist Destruction Interpositional pyrocarbon wrist arthroplasty has recently been proposed as an alternative to TWA for complete wrist destruction. Promising results were recently published but further experience is needed to validate this new concept.

20 Orthopaedica Belgica 2015 www.ob2015.org 21 Hemi Wrist Arthroplasty (HWA) for chronic or acute advanced wrist destruction I3 TRAPEZIOMETACARPAL JOINT REPLACEMENT. ARE NEW DESIGNS For chronic advanced wrist destruction BETTER? As stated above, the use of TWA for advanced wrist destruction in high demand N. Hollevoet patients is questionable since there is a high risk of implant loosening, particularly Dept. of Orthopaedic Surgery and Traumatology, Ghent University at the carpal side. Several authors recently proposed to use a HWA using the Hospital, Ghent, Belgium radial component of currently available TWA. Experiences are preliminary but the designs are evolving and HWA may become a new option when dealing with The first total trapeziometacarpal joint prosthesis was designed in 1971 by Jean chronic wrist destruction in high demand patients. Yves de la Caffiniere. It resembles a small hip prosthesis and consists out of two components: a polyethylene cup and a mono-block metal stem, neck and For acute advanced wrist destruction (so called “irreparable DRF”) in the elderly head. Similar designs were developed including the Guepar, Braun, Steffee (11) Implant surgery at the acute stage for complex fractures in the elderly is an old and Roseland prosthesis (12). Also reversed prostheses were made with the concept that has been validated for the hip, knee, shoulder and elbow. This metal head and neck on a pedestal fixed in the trapezium and plastic stem with concept emerged only a few years ago for DRF in the elderly. Indeed some DRF cup in the base of the first metacarpal (Mayo and Lewis prosthesis) (1). The first in this situation are beyond any osteosynthesis fixation possibilities. The use of a generation total joint arthroplasties were cemented (11). cast without reduction may leave a non- functional wrist with marked deformity. In the eighties and nineties cementless prostheses came on the market (Nahigian An external fixator is not a good option for most elderly patients. K-wires cannot (6) and Ledoux prosthesis (16)). Other uncemented models include the Bedeschi, hold any fragments in osteoporotic bones and are responsible for early skin Isoelastic and Link prosthesis (11). complications which are very cumbersome in this particular population. The use As a prosthesis with the shape of a saddle joint may be better than a ball and of bone substitutes has dramatically decreased. Our P.A.F. system is helpful to socket joint, a cemented resurfacement arthroplasty was developed (17). define the candidates to a resurfacing implant in such a situation. Healthy elderly Several additional changes have been made and nowadays implants without with relative high functional needs and co-morbidities self-dependent patients polyethylene are available made out of ceramic (Moje (5)) or with metal on metal with intermediate functional needs are good candidates to prosthetic surgery. articulations (Electra (13), Motec (8), Rubis 2 (2)). Instead of a mono-block stem, The Extra-articular Displacement severity score should be high along with a neck and head, modular implants such as the Arpe (9), Electra (13), Isis (14), Ivory volar fracture line distal to the watershed line and a circumferential metaphyseal (4), Maia (14) or Motec prosthesis (8) can be used. Unconstrained implants (Arpe comminution. (9), Electra (12), Ivory (4), Maia (15), Motec (8), second generation Guepar prosthesis The Intra-articular Displacement severity score should be high along with (10)) may show less loosening. Most of the recent prostheses are uncemented impaction and cartilage defect. with hydroxyapatite coating (Arpe (9), Electra (13), Ivory (4), Maia (15), cementless Current series are short but confirm that there may be a room for prosthetic version of the Roseland prosthesis (3)), other types have a titanium surface (Isis replacement of the distal radius at the acute stage in selected elderly patients. (14), Rubis 2 (2)) or are coated with resorbable calcium phosphate (Motec (8)). Further controlled prospective studies are necessary to validate this concept. Reported survival rates of old and more recent trapeziometacarpal joint arthroplasties were searched for in PubMed. Survivorship of all types was not available. In some studies different methods and end points were used. Therefore, it could not be determined which prosthesis had the best survivorship (7).

References 1. Cooney WP, Lindscheid RL, Askew LJ. Total arthroplasty of the thumb trapeziometacarpal joint. Clin Orthop Rel Res 1987;220:35-45. 2. Dunaud JL et al. The Rubis 2 trapeziometacarpal prosthesis: concept and operative technique. Chir Main 2001; 20:85-8. 3. Guardia C et al. Roseland prosthesis : Quality of life’s studies about 68 patients with a mean follow-up of 43.8 months. Chir Main 2010; 29:301-306. 4. Goubau JF et al. Clinical and radiological outcomes of the Ivory arthroplasty for trapeziometacarpal joint osteoarthritis with a minimum of 5 years of follow-up: a prospective single-centre cohort study. J Hand Surg.

22 Orthopaedica Belgica 2015 www.ob2015.org 23 5. Hansen TB and Vainorius D. High loosening rate of the MOJE ACAMO prosthesesis for treating I4 PIP ARTHROPLASTY WITH THE TACTYS PROSTHESIS osteoarthritis of the trapeziometacarpal joint. J Hand Surg; 2008; 33E:571-574. J.F. Goubau, B. Berghs, C.K. Goorens, D. Kerckhove, P. Van Hoonacker, 6. Hannula TT, Nahigian SH. A preliminary report: cementless trapeziometacarpal arthroplasty. J Hand Surg Am. 1999, 24:92-101. B. Vanmierlo 7. Huang K, Hollevoet N, Giddins G. Thumb carpometacarpal joint total arthroplasty: a systematic OrthoClinic, AZ Sint-Jan / AZ Sint – Lucas, Dept. of Orthopaedics and review. J Hand Surg Eur Vol 2014 Jan 19 (Epub ahead of print). Traumatology, Upper Limb Unit, Brugge; Universitair Ziekenhuis 8. Krukhaug et al. The results of 479 thumb carpometacarpal joint replacements reported in the Brussel, Vrije Universiteit Brussel (VUB), Dept. of Orthopaedics and Norwegian Arthroplasty Register. J Hand Surg 2014; 39E:819-25. 9. Isselin J. Results of the “ARPE” trapeziometacarpal prosthesis. Chir Main 2001; 20:89-92. Traumatology, Brussels, Belgium 10. Lemoine S et al. Second generation Guepar total arthroplasty of the thumb basal joint : 50 months follow-up in 84 cases. Orthop Traumatol Surg Res 2009 ;95 :63-69. The Tactys® PIP finger prosthesis was developed by a European team of surgeons 11. Lignon J, Friol JP, Chaise F. Historique des prosthèses totales trapézo-métacarpiennes. Ann from Belgium (1), Switzerland (1), and France (5) together with two engineers Chir Main 1990; 3:180-188. 12. Moutet F et al. The Roseland’s prosthesis. Chir Main 2001; 20: 79-84. from Memometal® in France (Bretagne) and commercialized by Memometal in 13. Regnard PJ. Electra trapeziometacarpal prosthesis: Results of the first 100 cases.J Hand Surg 2010. Its design was meant to be revolutionary: the UHMW polyethylene part 2006; 31B: 621–628. was designed to be fit on the P1 component, while the CrCo component was 14. Seng VS, Chantelot C. Isis trapeziometacarpal prosthesis in basal thumb osteoarthritis: 30 designed to fit on the P2 component. This feature enhances the longevity months follow-up in 30 cases. Chir Main 2013; 32:8-16 15. Teissier J, Alkar F. Trapeziometacarpal Maia prosthesis for basal thumb arthritis. A series of 100 since the friction forces are more concentrated on the concave part than on prosthesis with a minimum follow-up of 3 years. Chir Main 2011; 30:S77-S82. the convex part. This design should provide better long-term results regarding 16. Wachtl SW, Sennwald GR. Non-cemented replacement of the trapeziometacarpal joint. J Bone wear and stability. Moreover, the stems have been developed to obtain a full Joint Surg 1996; 78B:787-92. modularity, thus facilitating the composition of a prosthesis with a differently 17. Uchiyama S et al. Biomechanical Analysis of the Trapeziometacarpal Joint After Surface Replacement Arthroplasty. J Hand Surg. 1999; 24A:483-490. sized component in the bony medulla both proximally and distally.

Regarding surgical technique, we recommend a straight transtendineous approach, with desinsertion of the central slip ‘in toto’ allowing a clear exposure, an easy closure of the tendinous structure (with or without central slip bony reinsertion) in order to start immediate postoperative early active motion. Since indications regarding PIP arthroplasty may vary according to the indication rate of the surgeon (which can be very low), the variable outcome secondary to the tendency of the extensor apparatus to adhere, series are typically small in numbers.

The most recent series, is the one presented by the team from Nantes led by Philippe Bellemère, reports an average range of motion of 58 degrees in a series of 22 cases and a follow up of 33 months. The reoperation rate is lower than the pyrocarbon prosthesis and averages 18%.

PIP arthroplasty remains a challenging procedure: indications should be set very strictly, since the only certainty in absence of infection is relief of pain. The other features of success, especially range of motion, remain dependent of the quality of the surgery, but most of all the tendency of the extensor apparatus to adhere, thus decreasing the success rate regarding mobility.

24 Orthopaedica Belgica 2015 www.ob2015.org 25 I5 SCAPHOLUNATE INSTABILITY - TREATMENT WITH VOLAR OR DORSAL I6 NEW TECHNIQUES IN WRIST ARTHROSCOPY CAPSULAR REPAIR L. Van Overstraeten1, E.J. Camus2 L. Van Overstraeten1, E.J. Camus2 1Hand and Foot Surgery Unit, Tournai, Belgium; 2Clinique du Val-de- 1Hand and Foot Surgery Unit, Tournai, Belgium; 2Clinique du Val-de- Sambre, Maubeuge, France Sambre, Maubeuge, France The wrist arthroscopy is a minimally invasive technique that provides valuable Introduction information regarding the kinetics of carpus. Yesterday she only played a Scapholunate (SL) stability depends not only on the integrity of the interosseous diagnostic role. Now, it becomes a therapeutic procedure. ligament (SLIOL) but also on extrinsic volar and dorsal ligaments and capsular The wrist arthroscopy helped to define a new classification of Triangular attachments (DCSS). These structures constitute a true SL complex (SLC). The FibroCartilage Complex lesions. It is today involved in the repair of the TFCC lesion new EWAS classification of arthroscopical predynamic instability specifies the at all stages: debridement, foveal reattachment, distal radio-ular ligamentoplasty. stage 3 of Geissler and should be influenced with the lesional spectrum of SL Arthroscopy can treat ulnocarpal impingement with distal resection of the ulna. instability. The arthroscopic testing of the extrinsic components of SL complex It specified the scapholunate predynamic instability and intervenes in dorsal and assesses the dynamic status of them and specifies the lesional spectrum of palmar capsuloligamentous repairs. Some authors also described arthroscopic instability. This testing participates in the choice of the repair technique. tenodesis scapholunate. Arthroscopy assesses reduction and stabilization of the scaphoid fracture and Material and Methods can also help cheking of steps of nonunion treatment from debridement to bone Between 2010 and 2014, 18 arthroscopic capsuloligamentous repairs treat grafting and stabilization. symptomatic SL instability (12 dorsal, 3 volar and 3 combined repairs). Mean The reduction of complex articular fractures of the distal radius can be helped follow-up: 25 months. by arthroscopy. K-wire stabilisation in 5 dorsal cases. In distal STT osteoarthritis, the scaphoid can be pruned limiting destabilization by respect for scaphotrapezial ligaments. Results and Conclusions Carpal osteoarthritic collapse can also be treated using arthroscopy: Radial The dorsal and volar arthroscopic capsuloligamentous repairs are easy styloidectomy in SLAC 1, tendon interposition in SLAC 2, Proximal Row procedure. They allow to obtain a closing of the scapholunate widening with only Carpectomy or partial arthrodesis. one suture, an immediately arthroscopic stabilisation, an important improving of In Kienböck disease, lunate may be filled with bone replacement or decompressed pain, without stiffness. This procedure is indicated to treat symptomatic lesions of by radial subchondral drilling. the scapholunate complex when they are perfectly reducible (Garcia Elias stage 2 to 4). The type of arthroscopic repair (dorsal, volar or combined) is chosen Conclusion according to the lesional topography of SLIOL and extrinsic components of The wrist arthroscopy is no longer limited to a diagnostic role. It is involved in a scapholunate complex. Its clinical outcome is similar to the open capsulodesis. large number of therapeutic procedure. Its minimally invasive side decreases the The radiologic follow up is too short and then insufficient. A future long term disability duration. analysis will be necessary. Key words Key words Wrist Arthroscopy, CapsuloLiagamentous repair, SLAC, scaphoïde, Kienböck, Scapholunate Instability, Extrinsic ligament, Wrist Arthroscopy, Capsulo- TFCC Liagamentous repair

26 Orthopaedica Belgica 2015 www.ob2015.org 27 I7 ARTHROSCOPIC TESTING OF THE EXTRINSIC LIGAMENTS OF THE This in-vivo study confirms the responsibility of the extrinsic ligaments as CARPUS secondary stabilizers of the wrist, whose lesion are necessary to create a carpal E.J. Camus1, L. Van Overstraeten2 instability. The stage of loosening seems preponderant to the number of loosened 1Clinique du Val de Sambre, Maubeuge, France; 2HFSU, Tournai, Belgium ligaments. But the various extrinsic ligaments have several importance. The DIC is the most important stabilizer of the proximal carpal row, involved in SL and LT Scapholunate (SLIO) and lunotriquetral (LTIO) ligaments are essential to maintain stability. The RSC, LRL and ST ligaments play a role in SL stability. stability of the carpus. But cadaveric studies have shown the role of secondary stabilizers of extrinsic ligaments. Is it possible to confirm “in-vivo” the role of the Key Words extrinsic ligaments ? extrinsic ligaments, arthroscopy, testing Authors proposed an arthroscopic technique for testing extrinsic ligaments. Authors performed arthroscopy prospectively for 85 wrists with arthro- scannographic proof of wrist sprain. They tested all extrinsic ligaments accessible with arthroscopy. They correlated statistically the state of the extrinsic ligaments to the state of the intrinsic SLIO and LTIO ligaments (SSPS 1.9 software).

Testing shows 33 cases with a stable scapholunate space (Ewas 1-2) (38.8%), 42 moderate SL instabilities (Ewas 3) (49.4%), 10 large SL instabilities (EWAS 4) (11.8%). SLIO instability is directly correlated to the severity of loosening of extrinsic Radioscaphocapitatum (RSC), long radiolunate (LRL), Scaphotrapezial (ST) and Dorsal Inter Carpal (DIC) ligaments (p<.001). It is correlated with the number of loosened extrinsic ligaments (p <.05), and specially with the high grade of loosening (p<.001). A correlation is also found in case of combined lesion of SLIO and DIC ligaments (p<0.01).

Finally, SL instability is correlated with a mid-carpal part of the RSC ligament (p<0.05). It is not correlated neither with a radio-carpal part of the RSC, nor with the ST, nor with the DRC ligament lesion.

Lunotriquetral (LT) space was considered stable for 62 wrists (EWAS 1-2) (60%), moderately stable for 34 wrists (EWAS 3) (40%), there was no large instability (EWAS 4). Combined scapholunate and triquetrolunate lesions (stage II or more) were found in 25 cases (29.4%). The study found a significant correlation between LT instability and DIC ligament loosening (P<0.05). On the other hand, there was no significant correlation between LT instability and other extrinsic ligaments loosening.

Wrist arthroscopy allows to analyse loosening of different extrinsic ligaments. Thus it is the most precise exam to define the causes of carpal ligamentar instability.

28 Orthopaedica Belgica 2015 www.ob2015.org 29 I8 TREATMENT OF DISTAL RADIUS FRACTURES WITH ROBOTIZED I9 NERVE REPAIR WITH NEUROTUBES (ARTIS ZEEGO) PEROPERATIVE IMAGING A. Lejeune O. Barbier, T. Schubert, X. Libouton, V. Cordemans Hand Surgery, Chirec, Brussels, Belgium Orthopaedic Dept., Cliniques universitaires St-Luc, Brussels, Belgium The gold standard of peripheral nerve repair is nerve autograft when tensionless By young or demanding patients, results of treatment of distal radius fractures direct repair is not possible. However, donor-site and time consuming procedure are related to anatomical reduction of the fracture. Recent improvements include with a second incision, have led to use bioabsorbable synthetic nerve conduits as better evaluation of the lesions and more stable techniques of fixation with few a simply alternative to autologous nerve grafting for the repair of short peripheral secondary complications by volar locking plates. nerve defects of less than 30mm. These conduits are justified for gap involving small-diameter, noncritical nerve (e.g. digital and radial sensory nerve). Preoperative evaluation of the fracture include standard radiography analyzed according to specific measures and precise evaluation by CT-scan. Per-operative However, their use in large-diameter nerve deficits remains controversial. evaluation is performed by radioscopy and also by arthroscopy which gives a We report 55 patients who underwent repair of nerves using absorbable good evaluation of the joint and associated ligament injuries. New radiological nerve conduits and discuss the failed clinical outcomes. The reported cases techniques are also developed to give a precise per-operative evaluation of demonstrate the importance of evaluating the length, diameter, and function of the bone fragments, the joint and the position of the implant (not shown by nerves undergoing conduit repair. In large-diameter nerves, the use of conduits arthroscopy). The Artis Zeego (Siemens) is a robotized cone beam radioscopy should be carefully considered. with flat panel receptor. The robotized arm supports the radioscopy, maintains positions in memory and has predefined protocol to perform 360° rotations around the zone of interest to permit a complete analysis of the fracture site as a volume. It has already be helpful in our practice to perfectly place the plate and screws stabilizing the fragments of the radius. It guided also the reduction of severely displaced fragments not accessible to arthrsoscopic analysis. The limitations are currently the cost of the system, the radiation and the manipulation of the robot.

30 Orthopaedica Belgica 2015 www.ob2015.org 31 I10 ANATOMY AND BIOMECHANICS OF THE TMC JOINT - IN VITRO Clinically, our findings suggest that the DRL should be repaired or reconstructed AND IN VIVO STUDIES when disrupted to restore stability of the TMC joint and confirm the complexity of P. D’Agostino1, B. Dourthe1, F. Stockmans1,2, F. Kerkhof1, E. Vereecke1 trapezium and MC1 kinematics during thumb motion. An accurate understanding 1Development and Regeneration, Campus Kulak, KULeuven, Kortrijk; of TMC joint function is essential to develop more effective surgical procedures 2AZ Groeninge, Campus Loofstraat, Kortrijk, Belgium and to improve implant design.

Purpose The overall aim of our research is to improve our understanding of trapeziometacarpal (TMC) joint function. A first study focused on the role of the dorsoradial (DRL) and anterior oblique (AOL) ligaments in stability of the TMC joint. The aim of the second study was to quantify the in vivo kinematics of the TMC joint during extension-flexion (Ex-Fl) and abduction-adduction (Ab-Ad) of the thumb in healthy volunteers.

Methods For the in vitro study, 13 fresh-frozen cadaveric thumbs from 9 specimens were used. Length, width, and thickness of the AOL and DRL were measured on MRI and/or after dissection. Next, samples consisting of MC1-AOL-trapezium and MC1-DRL-trapezium were subjected to cyclic loading in displacement-controlled tests. The obtained force-displacement curves were used to calculate stiffness and hysteresis of each sample. For the in vivo study, the dominant hand of 16 asymptomatic female subjects (age range: 50-82yr) without signs of TMC joint osteoarthritis were CT scanned in positions of maximal thumb extension, flexion, abduction and adduction. The CT images were segmented and 3D surface models of radius, scaphoid, trapezium and MC1 were reconstructed for each sequence. Rotation, translation and helical axes for trapezium and MC1 were calculated between the extreme positions using in-house developed Matlab code.

Results The in vitro study showed that the DRL is significantly shorter and thicker, and has a higher stiffness than the AOL, which is thin and ill-defined. The kinematical analysis demonstrated that Ex-Fl and Ab-Ad of the thumb result in rotation and translation of both MC1 and trapezium, with most motion occurring at MC1 including clear internal-external rotation. During both thumb motions, the helical axes of MC1 and trapezium are almost parallel and nonintersecting and located, respectively, in MC1 and trapezium.

Conclusions In line with recent studies on TMC ligament function, our results show that the AOL is relatively weak and compliant compared with the DRL; the DRL being the strongest and stiffest ligament of the TMC joint. The kinematical analysis demonstrated that Ex-Fl and Ab-Ad of the thumb result in rotation and translation of both MC1 and Trap, with rotation of MC1 being most important.

32 Orthopaedica Belgica 2015 www.ob2015.org 33 I11 CLINICAL APPLICATIONS OF BIOMECHANICAL RESEARCH IN I12 ANATOMICAL AND BIOMECHANICAL ASPECTS IN THE FLATFOOT ELBOW / WRIST / HAND SURGERY G. Dereymaeker F. Schuind, F. Moungondo Foot & Ankle Surgery, Dept. of Biomechanics, Catholic University of Leuven, Université libre de Bruxelles, Erasme Hospital, Brussels, Belgium Belgium

Applied biomechanical research allows to answer many questions of the everyday The foot with his very specific anatomy, with the talus as the keystone of the arch surgical practice – many of these problems cannot be adequately solved by of the human foot, provides a powerful aid during walking, running, jumping, clinical research. For example, at the elbow, is the ulnar nerve under tension and allows in an adaptive way locomotion over uneven ground and up or down after total elbow arthroplasty (TEA)? In case of malpositioning of a TEA (which hill. Changes in the biomechanics of the foot can alter the shape of the foot. An is not exceptional in highly destroyed joints), is the function and in particular imbalance in the forces that tend to flatten the arch and those that support the the range of motion affected? Are there risks of early loosening? Does a bipolar arch can lead to loss of the medial longitudinal arch. The arch provides shock radial head hemi-arthroplasty sufficiently restore the elbow stability, in the usual absorption in the early stance phase of gait, and a stiff lever arm for propulsion situation of a deficient medial collateral ligament? At the wrist, does Kienböck’s forward by the triceps surae in the late stance. disease result from abnormal stresses applied on the lunate, and is it possible to reduce these stresses to limit the progression of the disease? At the hand, what The main stabilizers of the arch are: are the forces applied to the sutured flexor tendons? These are some questions • The plantar fascia stretches from the medial calcaneal tuberosity to the that over the years the authors have studied in the laboratory, in collaboration bases of the toes, across the metatarsal area. By binding the bases of the with basic scientists. Answers have been provided to the surgical community. arch together, it limits spreading of the base and, secondarily, collapse of the apex. The plantar fascia is the most important passive stabilizer of the arch (Kitaoka 1994). • The spring ligament (superior and inferior plantar calcaneonavicular ligaments), which limits descent of the talar head. It is continuous with the medial talonavicular capsule and superficial deltoid ligament, which limits medial deviation of the talar head. Also called the coxa pedis. • The tibialis posterior tendon, inserted primarily into the navicular tuberosity, with distal slips into medial 3metatarsal bones except the talus. The function of the tibialis posterior is of great importance. It fires in early stance, mainly eccentrically, to limit midfoot abduction and provide extra support for the spring ligament. • The interosseous talocalcaneal ligament limits gliding descent and medial deviation of the talus. • The long and short plantar ligaments and the plantar ligaments of the individual joint capsules

The main factors that contribute to an acquired flat foot deformity are excessive tension in the triceps surae, obesity, PTT dysfunction, or ligamentous laxity in the spring ligament, plantar fascia, or other supporting plantar ligaments.

Too little support for the arch or too much arch flattening effect will lead to collapse of the arch. Acquired flat foot most often arises from a combination of too much force flattening the arch in the face of too little support for the arch.

34 Orthopaedica Belgica 2015 www.ob2015.org 35 I13 HINDFOOT ALIGNMENT: SPATIAL INSIGHTS OUT OF NOVEL Results MEASUREMENTS IN 3D WEIGHT BEARING CT The angles differed between clinical measurements, radiographs and pedCAT CT A. Burssens (P > 0.01), but showed a positive correlation [Spearman’s correlation coefficient Resident Orthopaedic Surgery, Dept. of Orthopaedic Surgery, Heilig- Clinical/Rx = 0.61, Clinical/CTLA=0.61 ,Clinical/CTTC = 0.72, Rx/CTLA = 0.66, Rx/ Hartziekenhuis, Lier, Belgium CTTC= 0.62 (P < 0.05)]. Further findings showed a mean clinical hindfoot angle of 24.3° (ICC =0.79), a mean radiographic hindfoot angle of 9.1° (ICC =0.82), a mean Background CTLA hindfoot angle of 11.2 (ICC = 0.71), a mean CTTC hindfoot angle of 13.1° Surgical correction of hindfoot malalignment remains challenging due to the (ICC =0.81), a mean tibiotalar shift of 10.4mm (ICC=0.86), a mean subtalar angle of complex anatomy and the influence of weightbearing on the bony structural 72° (ICC = 0.88), mean tibial inclination angle of 3.9° (ICC = 0.84) and and mean composition. In order to obtain an accurate correction, a precise measurement talar tilt of 7.8° (ICC = 0.91). of the malalignment is paramount. This is currently performed on a standard weigthbearing by use of the long axial hindfoot angle, but is hampered by Conclusion and Clinical Relevance superposition of the bony anatomy. Conventional CT-scan contains more The proposed talcalcaneal (TC) hindfoot alignment angle, measured with a accurate anatomical information but lacks the possibility of weigthbearing. cone beam weight bearing CT shows a positive correlation with both clinical Recent technology developed therefore weight bearing cone beam CT-scan and previous radiological long axial (LA) measurements. It seems to be the most to overcome both problems. The effective radiation dose of these devices is precise way to document valgus alignment of the hindfoot and therefore we comparable to five traditional radiographs. would advocate its use in clinical practice. The lateral tibiocalcaneal shift, on which the angle is based, can help the surgeon in determining how much translation is Objective necessary to obtain a neutral alignment during a calcaneal osteotomy. To introduce novel measurement methods, which can be used to determine hindfoot alignment in weight bearing CT in correlation with clinical findings and Level of evidence: N/A previous measurements.

Methods Thirty valgus feet were included, in which standard digital radiographs with full weight bearing in standing position, long axial view and weight bearing CT (pedCAT scan) were obtained. The following angles were measured by two different investigators: clinical hindfoot alignment, long axial hindfoot angle both on long axial (LA)view and weigthbearing CT, novel talocalcaneal (TC) hindfoot angle, talocalcaneal shift (distance from a neutral alignment), subtalar angle, tibial inclination angle and talar tilt. A correlation was made between both clinical, radiological and CT findings. An intraclass correlation coefficient was used to assess rater reliability.

Study Design Radiographic measurements

36 Orthopaedica Belgica 2015 www.ob2015.org 37 I14 INFLUENCE OF THE GASTROCNEMIUS CONTRACTURE IN THE I15 FLEXIBLE AND RIGID FLATFOOT IN CHILDREN: ETIOLOGY, CLINIC GENESIS OF A FLATFOOT AND TREATMENT A. Witteveen P.L. Docquier Sint-Maartenskliniek, Nijmegen, The Netherlands Paediatric Orthopaedic Surgery, Cliniques Universitaires Saint-Luc, Brussels, Belgium Gastroc equinus as a legacy of the atavistic trait might be an underestimated cause of the development of a flexible flatfoot. Etiology The physical presentation of gastroc equinus as well as the possible treatment Flexible flatfoot is one of the most common “deformity” encountered by pediatric will be discussed. orthopaedic surgeon it remains questionable if it is a deformity. There is a physiological spontaneous development of the longitudinal arch with the growth of the child. A depressed longitudinal arch remains in approximately 23% of the adult population. Of this population, approximately two thirds have a flexible, hypermobile flatfoot with normal or increased mobility of the subtalar complex and ankle joint. Approximately one fourth of flatfeet exhibit a contracture of the triceps surae, The remainder of flatfeet are characterized by more rigidity of the subtalar joint, typically seen with tarsal coalitions.

Clinic Clinically, the heel shows excessive eversion during weight bearing, and the forefoot is usually abducted, producing a midfoot sag with lowering of the longitudinal arch. If flexibility of the hindfoot and arch reconstitution are not demonstrated on the tiptoe test, then other conditions must be considered, especially if there is a complaint of pain. Particular attention to the Achilles tendon is important because a contracture tends to make hypermobile flatfeet symptomatic.

Treatment Both footprint and radiographic studies of the child’s foot demonstrate that the longitudinal arch develops during the first decade of life, so no treatment is indicated in case of asymptomatic flatfoot. There has been suggested that shoes may be detrimental to development of the longitudinal arch. Controlled prospective randomized studies on the effect of shoe modifications and inserts on development of the arch have failed to demonstrate any effect. If an Achilles tendon contracture is present, stretching exercises are an appropriate form of management. These children may have symptomatic calluses under the head of the plantar flexed talus associated with the Achilles tendon contracture. Surgical management of a true hypermobile flatfoot is reserved for a patient who has intractable symptoms unresponsive to shoe or orthotic modifications and who is unable to modify the activities that produce pain. Surgical correction, truly a last resort for this normal variant, should emphasize joint-sparing procedures.

38 Orthopaedica Belgica 2015 www.ob2015.org 39 I16 INDICATIONS FOR SUBTALAR ARTHROEREISIS IN CHILDREN AND Flatfeet may be classified in four groups with specific surgical indications: ADULTS 1. Subtalar planovalgus: in which apex is at the level of the talonavicular A. Viladot joint. Indicated surgery is talocalcaneal screwing (horserider) or subtalar Barcelona, Spain arthroereisis. 2. Mediotarsal planovalgus: in which apex is at the level of the cuneonavicular Arthroereisis is a surgical procedure described to limit, but not eliminate, the joint. This foot is treated by lateral column lengthening. movement of a joint where there is a problem of excessive mobility. 3. Combined planovalgus: association of problems at the level of the In the case of flatfoot, arthroereisis, in addition to limiting the excessive mobility talonavicular and at the cuneonavicular joints. of the subtalar joint, corrects the deformity by maintaining the physiological 4. Cavoplanus foot: association of a planus of the medial column and a cavus position of the talus over the calcaneus. of the lateral column. Surgery consists of shortening of the medial column. The indications for arthroereisis in children are the following: In case of tarsal coalition, coalition resection may be indicated. An original • Severe flatfoot, which is unresponsive to conservative treatment. In our method using patient specific instruments is presented. experience, this is very uncommon: only 0,5% of patients with flatfoot. • Symptomatic flatfoot, secondary to tarsal coalition. • Flatfoot in the context of certain neuromuscular diseases. In these cases, the deformity is usually accompanied by some of the following “risk signs” which might lead us to predict a poor outcome. • Retraction of the Achilles tendon. We have found this to be present in approximately 90% of cases. During surgery, elongation of the tendon must be performed to correct the deformity. • Insufficiency of the posterior tibial tendon usually associated with an accessory or prominent navicular. In these cases, it is necessary to perform resection of the same and anchor the tendon to the navicular. • Stiffness of the hindfoot. In children, this is usually related to tarsal coalition and often accompanied by retraction of the peroneal tendons. In such cases, resection of the coalition is required to correct the deformity.

In adults, arthroereisis is indicated in Stage II posterior tibial dysfunction. In these cases, the tendon is elongated or broken but the deformity is still flexible. Before indicating arthroereisis, we should ensure that, in addition to the reducibility of the deformity, there are no signs of degeneration in the subtalar joint. If such signs exist, we should consider arthrodesis.

It has been shown that, in stage II, a simple repair of the posterior tibial tendon alone leads to a poor outcome in the short to medium term. This is due to the fact that, if the valgus heel is not corrected, the pronator moment of the hindfoot persists, causing a new injury to the tendon due to overloading. In our opinion, the goal of the surgical technique is, on the one hand, to perform the repair of the tendon (suture, augmentation, transfer of the F. D. L…) and, on the other hand, to keep the heel properly aligned by means of the arthroereisis.

40 Orthopaedica Belgica 2015 www.ob2015.org 41 I17 ARTHRORISIS WITH CALCANEOSTOP SCREW IN CHILDREN I18 TRAUMATIC FLATFOOT CORRECTS TALO-1ST METATARSAL-INDEX (TMT-INDEX) K. Buedts M. Richter Dept. of Orthopaedics, ZNA Middelheim, Antwerpen, Belgium Dept. for Foot and Ankle Surgery Nuremberg and Rummelsberg, Hospital Rummelsberg, Schwarzenbruck, Germany Obviously the better know pathology presenting a flatfoot deformity is the Acquired Flatfoot due to tib. post/springligament degenerative disease. Arthrorisis with calcaneostop screw is one option for the treatment of flatfoot (Pes abductoplanovalgus) in children. The aim of the study was to analyze the Any post-traumatic malalignment can provoke a valgisation of the hind-foot, amount of correction (for example talo-1st metatarsal-index (TMT-Index)) and depending on the deformity forces and the inability to achieve a good reduction clinical outcome including pedographic assessment. and stable fixation.

In a prospective consecutive non-controlled clinical follow-up study, all patients Great concern has to be given to the medial structures of the ankle. A subtle that were treated with arthrorisis with calcaneostop screw from September 1st instability of the deltoid/spring ligament complex, can provoke a valgus instability 2006 to August 31st, 2009 were included. One foot was operated at a time, and of the ankle. the contralateral foot was operated 3 months later if indicated. Postoperatively, 15kg partial weight-bearing was performed for 6 weeks. The screws were Last but not least, the midfoot plays an important role in the maintaining of removed after 2-year-follow-up. the medical arch of the foot. It goes for itself that a missed Lisfranc injury or a Assessment was performed before surgery, at two-year-follow-up, and at degenerative Lisfranc articulation can give rise to a painful flatfoot deformity. 2.5-year-followup. The assessment staging of posterior tibialis insufficiency, radiographs with full weight bearing (TMT-Index), pedography, and Visual-Analogue-Scale Foot and Ankle (VAS FA).

18 patients / 31 feet were included in the study (age, 10.6 (8-12), 45% male). No complications were observed. In comparison with the preoperative parameters, the parameters posterior tibialis insufficiency stage, percentage of increased pedographic midfoot contact area and force were decreased, and TMT dorsoplantar/lateral/-Index and VAS FA scores were increased at both followups (each p<.05). The parameters did not differ between followups (each p≥.4).

All relevant parameters (stage of posterior tibialis insufficiency, TMT dorsoplantar/ lateral/-Index, pedographic midfoot contact area and force, VAS FA) improved after arthrorisis with calcaneostop screw (before and after screw removal) in pes abductoplanovalgus in children. Since the complication rate is very low, this method allows safe and predictable correction.

42 Orthopaedica Belgica 2015 www.ob2015.org 43 I19 RECENT INSIGHTS IN ANATOMY, PATHOLOGY AND CLASSIFICATION OF TIBIALIS POSTERIOR DYSFUNCTION M. Guelfi1,3, R. Mirapeix2, V. Salini3 1Orthopaedic Division, Montallegro Hospital, Genova, Italy; 2Human Anatomy and Embryology Unit, Dept. of Morphological Sciences, Autonomous University of Barcelona, Barcelona, Spain; 3Orthopaedic and Traumatology Division, University “G. d’Annunzio” of Chieti and Pescara, Chieti, Italy

Introduction Adult acquired flatfoot deformity is generally associated with a collapsing medial longitudinal arch and progressive loss of strength of the tibialis posterior tendon. It is most commonly associated with posterior tibialis tendon (PTT) dysfunction Histologic Findings or rupture that can have an arthritic or traumatic cause. The progressive collapse Within portion where PTT turns around medial malleolus there are microscopic of the medial longitudinal arch leads to the development of many secondary and macroscopic characteristics for which the tendon is also called “Gliding deformities including abduction of the forefoot, calcaneus valgus, plantar flexion Tendon”. of the talus and fixed forefoot varus – supination deformity. In the gliding part the tendon structure differs from a typical traction tendon: Many scientific papers investigate on epidemiological factors as causes that this part is characterized by fibrocartilage. In the past some authors have lead to this pathology, we may resume these in: anatomic, micro-traumatic and systemic (1-2). misinterpreted the presence of fibrocartilage as a metaplasia or degeneration. In 1992, Holmes and Mann (1) suggested, reviewing a case series of 67 patients Now various studies have shown that the occurrence of fibrocartilage within (average age of 57 y/o) that PTT dysfunction or rupture occurs, in part, to gliding part of the PTT is a physiologic finding (5-6). degenerative changes of the tendon. In fact, 60% of these Pts. had a positive history for one or more risk factors such as: • Hypertension • Obesity • Diabetes mellitus • Previous surgeries • Collagen changes from aging

Materials and Methods Vascular Findings We evaluated the literature of the last 30 years on the topic dysfunction and/ In 1990 Frey et al. (7) described micro vascularization using conventional injection or rupture of the PTT and its causes. Thirty years of scientific papers were methods (Spalteholtz technique) (8) founding no evidence for an avascular zone. selected and compared to our clinical experience (153 cases from 1997 to 2014 However they suggested that the tendon has a reduced blood supplied zone in for all grades and treated either conservatively or surgically) and to anatomical the retromalleolar region. experience at the Autonomous University of Barcelona. While Petersen in 2002 (9) underlined the presence of just a few studies on the vascularization of PTT, today we can affirm that literature is certainly more Anatomy rich and methods to evaluate the vascularization of the tendon are different and Macroscopic Aspect more evolved. The anatomy of the PTT is well known, the muscle tendon junction is located in the medial posterior portion of the lower third of the leg. Distal insertion is on Petersen in 2002 used a technique that involves the simultaneous injection into the tubercle of the navicular bone, with plantar expansions going to reinforce the anterior and posterior tibial artery of the leg in fresh frozen bodies with a the medial and plantar talo – navicular joint capsule (Coxa Pedis). Tendon length solution of Technetium 99, Indian ink and gelatin. With this technique he has is from 12 to 15 cm and its cross section has an oval shape with a diameter from shown that the majority of “blood supply of the posterior tibial tendon is by 12 to 6-7 mm. In its intermediate portion PTT flexes about 80° anteriorly rotating posterior tibial artery” and that the portion of the tendon that curves around the behind the medial tibial malleolus (3-4). malleolus is not vascularized.

44 Orthopaedica Belgica 2015 www.ob2015.org 45 In 2006 Prado et al. (10) edit a study whose aim was “to determine if there is a Pathology correlation between the area most frequently affected by degenerative lesions Posterior tibial tendon dysfunction (PTTD) is most commonly a degenerative of the PT tendon and an area of decreased vascularization in this tendon. The process that leads to tendinosis and elongation of the primary dynamic stabilizer, most commonly used method for studying vascularization of a structure are intra- the posterior tibial tendon (PTT). Elongation of PTT influence its structure and arterial injections of dye followed by radiographic contrast (microarteriography) function, determining a inflammatory tendinopathy with formation of fissures or direct observation of the vascular tree under light microscopy. In this study, unable to heal. These can lead to partial or complete tears (12). the vascular density of the PT tendon was calculated after direct observation under a light microscope of histologic cuts stained with Masson’s trichrome”. According to this study there are no differences among the different sites of the PT tendon.

Manscke et al. in 2014 studied arterial anatomy of the PTT injecting anterior tibialis, posterior tibialis and peroneal arteries with India Ink and Ward’s Blue Latex (11). The specimens used for macroscopic analysis were debrided with sodium hypochlorite to expose the extratendinous anatomy. For the microscopic analysis, the tendon was cleared using a modified Spälteholz technique to expose the intratendinous vascular anatomy. Authors reported that macroscopically, an average of 2.5 ± 0.7 vessels entered the tendon proximal to the navicular insertion. Failure of clinical management may lead to progression of tendinosis and In 28 of 30 specimens (93.3%) vessel entered 4.1 ± 0.6 cm proximal to the medial partial tears. With or without rupture, tendinosis and the resultant PTTD result in malleolus and in 24 specimens (80.0%) vessel entered 1.7 ± 0.9 cm distal to the abnormal foot mechanics and contribute to acquired flatfoot deformity. medial malleolus. Microscopically, an average of 1.9 ± 0.3 vessels entered each tendon proximal to the navicular insertion. Twenty-seven specimens (90%) had a Classification vessel entering the tendon 4.8 ± 0.8 cm proximal to the medial malleolus and all Posterior tibialis tendon dysfunction is often misdiagnosed and overlooked but 30 specimens (100%) had a vessel entering the tendon 1.9 ± 0.8 cm distal to the is getting more frequent in the foot and ankle specialist’s office. This is also due medial malleolus. In all specimens, a hypovascular region was observed, starting to increasing of obese patients population. 2.2 ± 0.8 cm proximal to the medial malleolus and ending 0.6 ± 0.6 cm proximal Coughlin (13) reported about the most simple classification that define the to the medial malleolus with an average length of 1.5 ± 1.0 cm. The insertion of the problem in two stages: tendon was well vascularized both on microscopic and macroscopic specimens. • Stage 1: Tenosynovitis: acute swelling posterior tibial tendon, able to perform Their conclusions were that PTT is supplied by 2 vessels, these enter the tendon single limb heel rise. approximately 4.5 cm proximal and 2.0 cm distal to the medial malleolus. In • Stage 2: Definitive rupture. addiction retromalleolar region has low blood supply. Coughlin himself stated that this classification is really poor and not able to define indications to treatment, in the same lesson he empathized the Myerson’s classification.

Johnson and Stroem (14) has been for a long time the most used classification: • Stage 1: Peritendinitis and tendon degeneration but no tendon elongation, symptoms include pain and swelling along the posterior tibial tendon. • Stage 2: Posterior tibial tendon elongates and a supple flat foot deformity develops. • Stage 3: Hind foot rigid in a valgus position with rigid flatfoot deformity.

46 Orthopaedica Belgica 2015 www.ob2015.org 47 In 1996 Myerson published his classification that is universally used and divided 6. Petersen W, Stein V, Bobka T. Structure of the human tibialis anterior tendon. J Anat. 2000 into four stages (15): Nov;197 Pt4:617-25. 7. Frey C. Shereff M. Greenldge N. Vascularity of the posterior tibial tendon.J Bone Joint Surgery • Stage 1: pain over posterior tendon, able to perform single heel rise test, (Am) 1990;72-A:884-8. hindfoot flexible (tenosynovitis). 8. Spalteholz KW. Über das Durcksichtigmachen von menschlichen und tierischen präparaten. • stage 2: valgus angulation of heel, lateral hindfoot pain, flexible hindfoot, Leipzig: Hirzel, 1914. cannot perform single limb heel rise test (soon after rupture). 9. Petersen W. Hohmann G. Stein V. Tillmann B. The blood supply of the posterior tibial tendon. J Bone Joint Surg Br. 2002 Jan;84(1):141-4. • Stage 3: valgus angulation of heel, lateral hindfoot pain, flexible hindfoot, 10. Prado PM. De Carvalho AE Jr. Rodriguez CJ. Fernandez TD. Mendes AM. Salomao O. Vascular cannot perform single limb heel rise test (moderate after rupture). Density of the Posterior Tibial Tendon: A Cadaver Study. Foot & Ankle International 2006. Vol. • Stage 4: rigid forefoot, rigid hind foot,valgus angulation of talus (with 27 (8): 628-631. abducted forefoot), “too many toes sign” (chronic rupture). 11. Manske MC. McKeon KE. Johnson JE. McCormick JJ. Klein SE. Arterial Anatomy of the Tibialis Posterior Tendon. Foot & Ankle International January 2014:1-8. 12. Giannini S. Vannini F. Bevoni R. Romagnoli M. Digennaro V. Trattamento chirurgico delle lesioni In 2011 De Orio emphasized the clinical relevance of the classification, the disease del tibiale posteriore. Progressi in medicina e chirurgia del piede Vol. 16 “Tendinopatie del stage determines the right treatment for PTTD and underlines clinical signs to piede e della caviglia”: 73-85. Ed. Timeo Bologna 2007. evaluate correctly the patient and indicates the most appropriate correction (16- 13. Coughlin M. Posterior tibial tendon dysfunction, diagnosis & conservative treatment. Hand out: Sports medicine of the foot & ankle course. 103-108 Palm Springs 2001. 17). Another useful clinical classification is reported by Richter in 2013 (18), this 14. Johnson KA. Stroem DE. Tibialis posterior tendon dysfunction. Clin. Orthop. Rel. Res. 1989. also divides the disease into four stages taking into account the clinical signs of 239:196. the disease: 15. Myerson M. Adult acquired flatfoot deformity. J bone Joint Surg. 1996: 78A:780-791. • Stage 1: single leg heel rise possible, heel moves to varus during heel-rise. 16. DeOrio J.K. Shapiro S. A. McNeil R.B. Stansel J. Validity of the Posterior Tibial Edema Sign in Posterior Tibial Tendon Dysfunction. Foot Ankle Int, February 2011; 32(2):189-192. • stage 2: single leg heel rise possible, heel moves to neutral during heel-rise 17. Walters JL. Mendicino SS: The flexible adult flatfoot: anatomy and pathomechanics. Clin Podiatr • Stage 3: single leg heel rise possible, heel stays in valgus during heel-rise Med Surg. 2014 Jul;31(3):329-36. • Stage 4: single leg heel rise is not possible. 18. Richter M. Zech S. Lengthening osteotomy of the calcaneus and flexor digitorum longus tendon transfer in flexible flatfoot deformity improves talo-1st metatarsal-Index, clinical orutcome and pedografic parameter.Foot & Ankle Surgery 2011;11:56-61. In 2014 Peterson proposed subdivision of the stage IV into stage IV-A and IV-B. 19. Peterson KS. Hyer CF. Surgical decision making for stage IV adult acquired flatfoot disorder. Clin In stage IV-A ankle is valgus and without significant tibiotalar arthritis. In IV-B rigid Podiatr Med Surg. 2014 Jul;31(3):445-54. or flexible ankle valgus with significant tibiotalar arthritis. Division of stage IV in A and B is important in determining the appropriate surgical indications: IV-A are treated with ankle joint-sparing procedures, IV-B with ankle joint destructive procedures (19).

Conclusions Anatomy and vascularization expose posterior tibial tendon to major degenerative disorders until the rupture. Literature of the last thirty years shows a low blood supply zone of the gliding part of the tendon. Recent classifications of PTT disorder consider not only clinic but also instrumental images allowing choosing best surgical treatment.

References 1. G.B.Holmes Jr. R.A. Mann. Possible Epidemiological Factors Associated with Ruptur of the Posterior Tibial Tendon. Foot & Ankle Vol. 13, No.2/February 1992. 2. Walters JL. Mendicino SS. The flexible adult flatfoot: anatomy and pathomechanics.Clin Podiatr Med Surg. 2014 Jul;31(3):329-36. 3. Testut L. Human Anatomy. Vol. 3. 454-455, U.T.E.T. 1923. 4. Józsa L., Kannus P. I tendini: anatomia, Fisiologia, Patologia. Vol 1: 28-84. Momento Medico 1999. 5. Ploetz E. Funktioneller Bau und funkionelle Anpassung der Gleitsehnen. Z. Orthop 1938. 67:212- 234. 48 Orthopaedica Belgica 2015 www.ob2015.org 49 I20 TIBIALIS POSTERIOR DYSFUNCTION - MY BEST THERAPEUTIC I21 DELTOID-SPRING LIGAMENT COMPLEX REPAIR IN ACQUIRED FLAT CHOICE IN STAGES I AND II FOOT DEFORMITY M. Richter S. Desmyter Dept. for Foot and Ankle Surgery Nuremberg and Rummelsberg, AZ Maria Middelares - Campus St-Jozef, Gentbrugge, Belgium Hospital Rummelsberg, Schwarzenbruck, Germany In acquired flat foot deformity (AFFD) - pes planus et abductus - there is typically Lengthening osteotomy of the calcaneus (LO) and flexor digitorum longus tendon an angular deformity of both the hindfoot and the midfoot. In stage two, the (FDL) transfer to the navicular is one option for the treatment of flexible flatfoot deformity is reducible and arises under load, signaling overstretching (sometimes deformity (FD). The aim of the study was to analyze the amount of correction and rupture) of medial tendons and ligaments. clinical outcome including pedographic assessment. The focus of interest in etiology and treatment has long been on the posterior In a prospective consecutive non-controlled clinical follow-up study, all patients tibial tendon but often there is no discontinuity and the presence of elongation with FD that were treated with LO and FDL from September 1st 2006 to August is unclear. There is, however, a growing interest in the function of and changes 31st, 2009 were included. Assessment was performed before surgery and at in the deltoid and spring (calcaneo-navicular) ligament complex. Basic anatomy 2-year-followup, and included clinical examination (with staging of posterior and biomechanics dictate that the deformity can occur with intact posterior tibial tibialis insufficiency) weight bearing radiographs (Talo-1st Metatarsal angles tendon but not with normal ligaments. Their dysfunction allows an abnormal (TMT), pedography (increased midfoot contact area and force), and Visual internal rotation (and plantar flexion) of the talus. Therefore, the reconstruction Analogue Scale Foot and Ankle (VAS FA). of these structures is essential.

112 feet in 102 patients were analyzed (age, 57.6 (13-82), 42% male). In 12 feet A modified method is presented to close the deltoid-spring interval, taking into (9%) wound healing delay without further surgical measures was registered. account the difficult biomechanical isometry in this area. The main goal is to All patients achieved full weight bearing during the 7th postoperative week. close the triangle formed by the tip of the medial malleolus, the medial tuberosity Until follow-up, revision surgery was done in 3 patients (fusion calcaneocuboid of the navicular bone and the sustentaculum tali. In this way, the talar head is joint (n=2), correction triple arthrodesis (n=1)). 101 feet (90%) completed 2-year- shifted laterally (external rotation of the talus), reducing the talonavicular joint followup. TMT dorsoplantar/lateral/index and VAS FA scores were increased, and the forefoot abduction. Bringing the talar head back over the sustentaculum and posterior tibialis insufficiency stage, pedographic midfoot contact area and helps in correcting the hindfoot valgus. Calcaneal slide osteotomy corrects the force percentage were decreased (each p<.05). remainder of the hindfoot valgus.

All relevant parameters (stage of posterior tibialis insufficiency, TMT angles and index, pedographic midfoot contact area and force percentage, VAS FA) were improved 2 years after LO and FDL transfer to the navicular in FD. The complication rate was low. This method allows safe and predictable correction.

50 Orthopaedica Belgica 2015 www.ob2015.org 51 I22 DOUBLE CALCANEAL OSTEOTOMY: HOW FAR CAN WE GO? I23 MY BEST THERAPEUTIC CHOICE IN STADIUM III : TRIPLE ARTHRO- G. Vandeputte DESIS AND HIS PRINCIPLES Heilig Hartziekenhuis, Lier, Belgium T. Leemrijse Foot and Ankle Institute, Clinique du Parc Léopold, Brussels, Belgium Performing a calcaneal osteotomy as part of a surgical reconstruction of a plano-valgus foot has become a well accepted and routine surgical step. Introduction Double and triple arthrodeses have been used extensively for the correction Many different calcaneal osteotomies have been described and none has been of rearfoot deformities. Traditionally, this has been accomplished through the proven to be superior to another. One can state that there is not one osteotomy incision described by Ollier which is not without complications, in the form of nerve damage, stretching and compromising the lateral soft tissues, or that can universally correct all hindfoot deformities in all feet. incompleted correction of the deformity. Therefore, it may become desirable to perform these procedures through lateral and anteromedial incisions to gain Since 1997 double osteotomies of the calcaneus have been reported. The adequate access to the subtalar, talonavicular, and calcaneocuboid joints for the first osteotomy corrects the valgus of the hindfoot by shifting the tuber of the preparation of the arthrodesis surfaces. calcaneus medially. The second osteotomy corrects the abduction of the foot by an opening wedge laterally (lateral column lengthening). By tailoring these two Methods osteotomies one can obtain a precise correction of the deformed foot. The authors performed a retrospective review of patients who had undergone triple or double arthrodesis using the lateral and anteromedial approaches over We confirm the good results obtained with these combined osteotomies a four year period between 2007 and 2010. Depending of the etiology of the and review the technique, which can be done minimally invasively (two small deformity, additional soft tissue procedures and osteotomies were performed. A incisions). total of 21 triple and double arthrodeses for severe planovalgus stage 3 deformity were included in this review and 6 cases for incompleted surgical correction of planovalgus deformity.

Results All of the patients of this review demonstrated a significant clinical improvement in rearfoot alignment and pain relief. Fusion following the primary surgery was achieved in all but one of the patients (a heavy smoker). Two patients presented superficial infection which were successfully treated by debridement and antibiotics. Three patients presented a remaining valgus deformity due to imbalance of the talocrural ligaments.

Conclusion We provide evidence to support that the lateral and anteromedial approaches for the correction of rearfoot deformities can be successfully used to achieve excellent exposure of the subtalar, talonavicular, and calcaneocuboid joints in order to correct the rearfoot deformity, avoiding the risks of wound healing and nerve damage associated with the Ollier approach.

52 Orthopaedica Belgica 2015 www.ob2015.org 53 I24 MY BEST THERAPEUTIC CHOICE IN STAGE IV FLATFOOT DEFORMITY I25 CAOS SYMPOSIUM: IMPROVING ACCURACY IN ORTHOPAEDIC B. Devos Bevernage SURGERY Foot and Ankel Institute, Kliniek Park Leopold, Brussel, Belgium O. Cartiaux, B. Innocenti, E. Thienpont

The clinical exam is the most important step in the evaluation of an advanced flat During this innovative, interactive session, the participants will learn about new foot deformity, because a few patients, classified as stage 3, are at risk being a options for improving accuracy in joint replacement. stage 4. Pain at the external malleolus, in the area of the deltoid ligament and/or also at the tibiotalar joint must indicate the need for a standing X-ray. The session program is based on a series of five “surgeon-engineer” tandems to talk each on a specific topic. Current technologies like navigation, patient- One must look for internal ligament distension, fracture of the external malleolus, matched instrumentation and robotics will be covered, as well as numerical sacking of the naviculocuneiform joint, ankle arthrodesis. modelling and new technologies. For each topic, the surgeon will start first Stress X-rays, Ct-scan or MRI may be helpful to confirm above mentioned and explain what he is still missing and he hopes to find back in the discussed pathologies. technology. The engineer will then answer to the surgeon’s questions and tell Conservative treatment always fails in this stage. if the technology state-of-the-art is able (or will be able) to help in this quest for better results or if the surgeon is hoping for too much. Surgery is demanding and patient depending. It varies from triple arthrodesis with In the second part of the session, there will be plenty of time dedicated to additional osteotomies or ligamentoplasties to panarthrodeses of the hindfoot. discussion and interaction with the audience. Focus will be on what surgeons The options will be discussed, showing the advantages and disadvantages of and engineers will be able to do if they sit close and talk together. each treatment. The moderators and organizers hope this format will be the standard for creating a new group called “CAOS Belgium”.

54 Orthopaedica Belgica 2015 www.ob2015.org 55 I26 SURGICAL NAVIGATION: WHAT DOES THE SURGEON WANT? 7. Prediction of the remaining laxity and kinematics that will occur after insertion J. Victor of the implant, before the bone cuts are made. Ghent University, Ghent, Belgium 8. Evaluation of range of motion, laxity, kinematics and integration with force measurement devices. Surgical navigation once held the promise to be a major breakthrough in 9. Automatic Integration of intra-operative findings in electronic file of the orthopaedic surgery. It was introduced in knee, hip and spine surgery. After patient. the hype and the initial enthusiasm was over, many surgeons abandoned the 10. Open software platform allowing research applications. technology and returned to the traditional instrumentation systems. Finally, government reimbursement cannot be directed exclusively to the Numerous publications showed improved alignment in the coronal plane implant but should support proven technology that increases accuracy and for navigated knee arthroplasty. However, the added value was considered reproducibility of implantation. insufficient, especially because surgical navigation was of little help in improving rotational alignment. In addition, the procedure could be cumbersome because of problems with the fixation of the reference frame to the bone, the integration of the software interface in the complicated OR environment, the lengthy registration procedure, and most of all, the loss of position tracking by the camera because of fluid or blood spill on the reflective markers. Still, surgical navigation has a huge potential as compared to other technologies that claim to improve positioning of implants: it offers instant, ‘live’ information, and it can integrate alignment, laxity, range of motion and kinematics. Other technologies, such as patient specific cutting blocks, can only offer measured resection guidance, based upon pre-operative imaging, without the above mentioned added value. It is certainly interesting to question why orthopaedic surgery has remained so conservative in its usage of tools, as we are still using mechanical (carpenter- like) instruments and blocks, oscillating saws and chisels. Most of this looks like a previous century toolbox, and is in sharp contrast with the steep evolution of automation, robotics and precision tools used in e.g. urology, cardiac surgery and anaesthesia.

This is the suggested wish list for the orthopaedic surgeon in the example of TKA: 1. Easy set-up and start-up, performed by OR nurse, without lengthy preliminary training. 2. Reproducible and fast fixation of reference frames to femur and tibia, if possible non-invasive. 3. Accuracy below 1 mm and 1°. 4. Reproducible definition of Cartesian coordinate systems for femur and tibia, based upon relevant landmarks. Especially references for defining the femoral and tibial axial planes are currently difficult to mark reproducibly. 5. Automatic integration between pre-op imaging with intra-op findings: augmented virtual reality. 6. Automated work-flow in the software, mitigating the need for active interventions to select surgical steps and windows.

56 Orthopaedica Belgica 2015 www.ob2015.org 57 I27 PSI, WHAT DOES THE SURGEON WANT? I28 ROBOTICS: WHAT DOES THE SURGEON WANT? R. De Vloo B. Stuyts Orthopedic Dept., AZ Klina, Brasschaat Sint-Augustinus Ziekenhuis, Wilrijk and AZ Sint-Jozef, Malle, Belgium

Patient specific instrumentation (PSI) for the use in total knee arthroplasty (TKA) Robotic assistance is a relatively new technology for unicompartmental (UKA) was introduced by the orthopaedic industry in 2008. Since the introduction very and total knee arthroplasty (TKA), as well as for certain aspects of total hip little changes have been made by the manufacturers to improve the usability of the planning software and the accuracy of the pinning and cutting guides. In this arthroplasty (THA). presentation, optimization of the preoperative planning and the peroperative The hypothesis and rationale for such systems is that robotic assistance may use of the guides is proposed. result in improved component positioning and alignment that influences long-term clinical outcomes. According to reports for TKA, for example, Checking, modification and approval of the preoperative default plan is crucial conventional surgery achieves neutral alignment (within 3° of the mechanical in TKA with the PSI technique. At the introduction of this innovative procedure, axis) only 75 percent of the time, and coronal suboptimal alignment greater than it was not clear how to look at the presurgical plan and how to modify it to 3° correlates with worse outcomes. achieve a good mechanical result during surgery with a nicely balanced flexion and extension gap and minimal soft tissue releases. The default plan does not allow for consistent good peroperative results and the personal experience of Overall, the use of robotics for TKAs and UKAs has demonstrated the ability the author is that almost every plan needs to be adapted preoperatively. to improve component positioning in some cases; however, no study has Although literature describes reliable and accurate restoration of the mechanical demonstrated improved functional outcome in near-term follow-up. This may be axis using the PSI technology, midflexion instability was a major problem in our due to limited sensitivity of clinical outcome measures or to the limited follow- first cases due to excessive external rotation of the femoral resection in the axial up period. Longer term follow-up will be needed to demonstrate whether the plane. The extra anteromedial soft tissue dissection to position the tibial guide improved positioning will result in clinically significant improvements in patient properly on the proximal tibia releases the anterior fibers of the superficial medial collateral ligament (MCL). The combination of the excessive external rotation of outcomes. the femoral implant and the additional release of MCL attributes to the midflexion instability. Over the past years we developed a different algorithm for the fine- Robotic systems have several drawbacks. They often require a preoperative CT tuning of varus, valgus and straight arthritic knees prior to approval of the default to perform the necessary image registration, thus exposing patients to additional plan. radiation over a typical preoperative TKA evaluation. All robotic procedures have been found to require additional surgical time in most circumstances. This raises Self-learning intelligent software should lead to customization of the default plan concern about the correlation of surgical time with infection risk. In addition, the for each individual surgeon. At the same time, this should allow for optimization of the default plan for surgeons with less PSI experience to improve their learning curve can be substantial, with a decrease in surgical time within about postoperative results. 20 cases. Finally, depending on the type of registration used, there can be a risk Positioning of a new tibial guide between the actual anterior and anteromedial of pain or fracture from the fixation system. position should avoid interference of the tibial guide with the medial collateral ligament and the patellar tendon, reducing the chance of midflexion instability. Perhaps the largest question underlying robotic surgery is the cost-benefit trade- Statistically analyzing the shape of the femoral and tibial guide and the ideal off. Incorporating robotics into a practice requires the upfront capital expenses position of the guides during surgery, engineers should provide a pressure for acquiring the robot, the additional costs for servicing the robot, and the button on the guides to allow for easy and correct registration of the guides. In our opinion, PSI technology should be more ambitious: our goal should be a generally increased cost of disposable equipment used for each surgery. The better restoration of the individual anatomy of the patient’s knee with repair of initial capital requirement can approach the $1 million mark for some systems. the joint line, the posterior condylar offset and also the anterior condylar offset, In an era of cost-benefit awareness, substantial evidence supporting improved allowing accurate correction of deformities in the coronal, sagittal and axial clinical outcomes must distinguish systems that are truly beneficial from systems plane. that support the marketing of a robotic service line.

Customization of an intelligent planning algorithm adapted to the surgeons Overall, the use of robotics in knee arthroplasty may have the potential to preferences, optimization of the ideal position of the pinning and resection guides and matching of the implants with the patients anatomy should be made deliver better implant positioning than conventional approaches, although some possible by the engineers and manufacturers. Only this way PSI technology will drawbacks - such as increased surgical time - also exist. allow us to improve the results of TKA. 58 Orthopaedica Belgica 2015 www.ob2015.org 59 Although no near-term clinical impact has been detected, the relationship I29 BEING INSPIRED BY THE HUMAN MUSCULOSKELETAL SYSTEM FOR between component positioning and long-term outcomes indicates that IMPROVED LOWER LIMB EXOSKELETONS AND PROSTHESES additional clinical studies are required to assess the true impact of the technology. B. Vanderborght, R. Ünal Surgeons should evaluate whether they believe such a system will aid in their Robotics & Multibody Mechanics Research Group, Vrije Universiteit technique to optimize their patient outcomes. Brussel, Brussels, Belgium

Despite these caveats, robotic assistance has the potential to be an exciting new An increasing number of robotics researchers have realized that in animals addition to the long list of technologies that have incrementally improved the and humans not only the brain creates the intelligence of the body, but that practice of arthroplasty. If robotic arthroplasty can be shown to result in improved the morphology and biomechanics have a great impact on the way animals component positioning that leads to better long-term outcomes, the cost-benefit and humans think and move. A critical role in this respect is played by the ratio may be favorable. This level of evidence will be particularly important in an neuromechanics of muscles, which have functional performance and control era of increasing emphasis on outcomes-based reimbursement. capabilities far in excess reached by artificial actuators. In traditional robotics, stiff actuators controlled as servomotor governed by the principle of “the stiffer the better”, produce high bandwidth control adapted to tasks requiring tracking of a desired trajectory with high accuracy. Many - mostly novel - applications requiring interaction with an unknown and dynamic environment including humans require dynamics that are not well suited to servomotors.

Therefore, Variable Impedance Actuators (VIA) are being developed, which are inspired by biological motor control, where the influence of muscle spring- like properties and their control are of great importance. In the presentation we will highlight the role of compliant elements to design improved lower limb exoskeletons for assistance and rehabilitation and prostheses.

60 Orthopaedica Belgica 2015 www.ob2015.org 61 I30 NUMERICAL SIMULATION. WHAT DOES THE SURGEON WANT? I31 EXPERIENCE IN CREATING CAOS IN FRANCE T. Scheerlinck P. Merloz Dept. of Orthopaedic & Trauma Surgery, UZ Brussel, Brussels, Belgium Clinique Universitaire d’Orthopédie Traumatologie, Université Joseph Fourrier, CHU A. Michallon, Grenoble, France Numerical simulation is a mathematical simulation technique that allows a quantitative representation of the evolution of a physical system. The technique Computer Assisted Surgery (CAS) systems were introduced in the late 80’s in is widely used in orthopaedic and trauma surgery, meanly as a research tool. the area of stereotactic neurosurgery in order to assist a surgeon in placing It allows investigating mechanical failure mechanisms of implants or bone, a probe deep in the brain without any direct visualization. The basic principle thermal consequences of the use of bone cement and loading patterns of the of CAS is to locate the three-dimensional position of surgical instruments in musculoskeletal system. the operative field and to display these instruments on pre or intra operative Compared to in vitro experiments and clinical studies, numerical simulation images. The general purpose of CAS technology is to increase accuracy, reduce allows testing different scenarios and many variables within a short time frame morbidity, obtain better clinical and functional results, offer the possibility of MIS and with limited resources. As such, it is a powerful research tool to explain (with ease and safety) and improve surgical protocols by allowing consistent failure mechanisms in orthopaedics and to define possible solutions that might post-operative studies. This technique is also referred as CAOS / Computer be worth further investigation with experimental methods. Assisted Orthopaedic Surgery, Surgical Navigation, Surgical Robotics, Surgetics, Computer Integrated Surgery, and AIM: Augmented Interventions in Medicine. One of the weaknesses of numerical simulations is the need for a validation From the early 90’s, three teams around the world were at the origin of the procedure to make sure the simulation represents what happens in reality. That concept of CAS: TIMC Lab (Ph. Cinquin, J Demongeot, J. Troccaz, S Lavallée) in validation procedure can be difficult, but is essential to avoid discrepancies Grenoble; University of Pennsylvania (A. Di Gioia) in Pittsburgh and University of between what happens in the real world and what has been calculated in the Bern (LP Nolte). virtual world. A second problem is that most numerical simulations use a single model that is supposed to be representative for most cases encountered in clinical The first CAS systems were introduced for spine surgery in the mid 90’s to practice. However, in most cases, the large amount of variability encountered in improve pedicle screws placement. The first computer aided spine surgeries clinical practice is not taken into account. were done in Grenoble, Montréal (LP Amiot) and Bern in 1995. In this domain, Moreover, the hypothesis that the results of numerical simulations can be two technologies are still in use: the CT-based navigation technique and the generalised to most clinical situation is often assumed, but not demonstrated. fluoronavigation system which can be considered as an alternative to CT-based systems. Nowadays, numerical simulation is undoubtedly recognised as an essential and powerful research tool. However, to be of direct practical use to surgeons, it will Since the end of the 90s, CAOS were under development for many clinical need to be not only reliable and validated, but also individualised to a patient’s applications for osteotomies and arthroplasties: THR, TKR, UKR, HTO… specific situation. As such, numerical simulations could evolve from a pure research tool that provides general answers to orthopaedic problems, towards Three new technologies were recently (in the late 2000’s) added to the a practical clinical tool that helps surgeons make the right choices for individual orthopaedic intra operative arsenal: 3D fluoroscope, Patient Specific patients. Instrumentation and new robots. The 3D isocentric fluoroscope is a new type of fluoroscope, able to provide intra-operative CT-like images and navigation assistance without the need of registration process. Patient’s CT data are used to simulate and plan preoperatively patient specific tools by using rapid prototyping and templating technology for different clinical applications (osteotomy, TKR, UKR, tumor resection). This technique uses a rapid prototyping technology to represent the shape of the bone in the region of the planned trajectories. Intra-operatively these templates were attached to the bone at their appropriate position, thanks to the precise representation of the bony surface and each drill can be carried out exactly as planned with the help of these templates.

62 Orthopaedica Belgica 2015 www.ob2015.org 63 The small robots such as “Bone Mounted Robot” can be fixed directly within I32 3D DEFORMITY IN SCOLIOSIS AND SUPPLY OF EOS the operating field because they are not very cumbersome. With CT-based T.S. Illés technology they demonstrated their ability to help the surgeon to perform Brugmann Hospital, Brussels, Belgium surgical tasks with a high degree of accuracy. Haptic robots are very promising devices: the robot is able to constrain the surgical tool tip to stay in a 3D area Hypothesis predefined on pre-op CT images in order to mill the internal shape of the implant The appearance of scoliosis in horizontal plane is not known because there was accurately. no tool for real 3D visualization of the entire spine.

Compared to conventional surgical methods, navigation provides generally a Design Analysis of scoliosis curves in horizontal plane using vertebra vectors. high degree of accuracy. For instance, in spine surgery, there is an evidence that navigation systems are better than conventional techniques in term of accuracy Introduction for pedicle screw placement especially in large spinal deformities or when spinal There is not enough information about the horizontal plane appearance of segments have been previously fused. scoliosis despite of its 3D nature. The Lenke classification for idiopathic scoliosis is suggested to be a 3D classification although it is only based on 2D images. The CAS is completely part of the Techniques for biomedical engineering and EOS is a new X-ray system with special software for 3D reconstruction of the spine. complexity management – computer sciences, mathematics and applications The vertebra vector, a simplified representation of the 3D reconstructed vertebra with their eight items: Modeling and Simulation in Medicine, Signals and Image based on known vertebral landmarks, is proposed to analyze mathematically the processing in Medicine, Medical Information Systems and database; Sensors curves especially in horizontal plane. and intelligent networks in health sciences, Modeling analysis and tools for disabilities, Learning and assistance to surgical procedures, e-Health, and Tissue Methods 814 cases of idiopathic scoliosis patients underwent, in standing position, to engineering and Implants. simultaneous AP and lateral X-rays using the EOS 2D/3D system. After Lenke classification of curves, 3D surface reconstructions were carried out by sterEOS 3D software. Following the creation of the vertebra vectors, they were placed in an individual coordinate system in order to determine the x, y, and z coordinates of their initial and terminal points. The obtained large database was analyzed mathematically using the K-means clustering algorithm (M-SVMs) software. In addition 95 idiopathic scoliosis cases were also studied in the same way before and after surgery.

Results In the same Lenke group, in spite of the same appearance of two curves in frontal and sagittal planes the horizontal view can be different. In each Lenke group it is possible to define different sub-groups in which the horizontal appearances are similar. During the progression of scoliosis the lateral displacement of the spine is more important than the increase of the vertebral rotation.

Conclusion Vertebra vectors allow visualization and precise characterization of scoliosis curves in all planes especially in the horizontal plane. In all Lenke groups, despite similar appearances in the frontal and sagittal planes, there are different horizontal appearances. The Lenke classification does not accurately characterize scoliosis curves in horizontal plane, so it cannot be considered as true 3D classification. The displacement of the vertebrae in the horizontal plane plays more important role in the progression and in the correction of scoliosis than the axial rotation of the vertebrae.

64 Orthopaedica Belgica 2015 www.ob2015.org 65 I33 SAFETY OF SUBLAMINAR BANDS IN SURGICAL CORRECTION OF I34 CERVICAL SPINE TRAUMA: RADIOLOGICAL PITTFALLS…. ADOLESCENT IDIOPATHIC SCOLIOSIS N. Allington P. Moens, A. Borgers, L. Moke, T. Dewilde CHR Citadelle, Liège, Belgium Pellenberg Hospital, Leuven, Belgium The growing child’s cervical spine has quite some particularities to be know to Introduction interpret adequately the lesions on X-ray and to properly handle the child. The aim of scoliosis fusion surgery is to stop curve progression and apply Special care has to be taken to transport the child (bigger head). Special attention three-dimensional correction in order to restore trunk height and to achieve a has to be directed toward the “abnormal” child-spine regarding authorized sport balanced spine in both the coronal and sagittal plane to prevent junctional curve progression in the unfused spinal segments. The golden standard of scoliosis activities, anaesthesiology…. fusion surgery has shifted over the past years. To this day hybrid constructs, In the “normal” child, cervical spine trauma is quite rare but can be devastating using sublaminar devices, as well as all-screw constructs proclaim to be the and other “images” are some variants of the normal… golden standard. There has been controversy about the safety of passing steel wires under the lamina into the spinal canal. Several case reports have been published in the past three decades concerning transient and permanent neurologic deficits, contributed to use of sublaminar wires. The goal of the present study is to assess the safety of sublaminar polyester bands in the instrumentation for adolescent idiopathic scoliosis.

Methods Patients: The institutional medical ethics committee approved current study. 72 patients with adolescent idiopathic scoliosis were included. The patient group consisted of 56 female patients and 16 male patients. Mean age at time of surgery was 16.7 years. Mean follow-up was 17.5 months. Technical aspects: All patients had instrumented posterior spinal fusion in our hospital between July 2008 and August 2012. Surgical technique consisted of hybrid instrumentation using hooks, pedicle screws and Universal Clamps. All patients had intraoperative neuromonitoring with motor evoked potential monitoring (MEP) and somatosensory evoked potential monitoring (SSEP).

Results The mean preoperative Cobb angle of the major curve was 60 +/-19°. The mean postoperative Cobb angle was 23 +/-13°. Intraoperative neuromonitoring changes were recorded in 9 of 72 patients (12.5%). Two patients had isolated MEP changes; another 2 had isolated SSEP changes and 5 patients both MEP and SSEP modifications. Three patients developed a transient neurologic deficit after surgery. Two of three patients with a postoperative neurologic deficit had intraoperative monitoring changes in both MEP and SSEP recordings. All three recovered without sequelae. We analyzed the recorded data for the moment of the monitoring changes and the surgical action performed at that time. We found no neuromonitoring changes during insertion or passage of the Universal clamps in our series.

Conclusion This paper has focused on the safety of modern hybrid constructs combining lumbar pedicle screws, apical Universal clamps and proximal hooks. Our results demonstrate that passing polyester bands like the Universal clamp under the lamina is safe technique in the correction of AIS. 66 Orthopaedica Belgica 2015 www.ob2015.org 67 I35 OUR EXPERIENCE IN GROWING RODS I36 EFFECTS OF PHYSICAL THERAPY ON POSTURAL PARAMETERS IN L. Miladi ADOLESCENTS SUFFERING FROM IDIOPATHIC SCOLIOSIS: A Dept. of Orthopedic Pediatrics, Necker-Enfants-Malades Hospital, PROSPECTIVE STUDY University Paris-Descartes, Paris, France S. Kachouri1, R. Elbaum1, F. Adam1, P. Mahaudens2 1Erasme University Hospital and 2Saint-Luc University Hospital, Brussels, Our experience in Growing Rods dates back to 1983, at first we used the Belgium Harrington rods, then from 1985 the CD rods. In the early 1990s, we performed many rib distractions by various non-specific devices. Objectives In the early 2000s, with Jean Dubousset we tried a growing rod expandable by Quantify the reproducibility of the evaluation of postural attitude in adolescents radio waves, in order to reduce the complication rate caused by the repeated with idiopathic scoliosis (AIS) to estimate the effectiveness of postural surgeries. In 2005, we used for the first time a growing rod powered by magnet in 30 cases. rehabilitation by physiotherapy treatment associated with the use of brace. From 2009 we use a more conventional device and applied a more advanced Evaluate the relationship between posture indices, characteristics of scoliosis and more rigorous surgical technique, waiting to use an automatic rod in the shape, and specific radiological parameters to validate the application of postural near future. assessment as an alternative to radiological monitoring.

For idiopathic or syndromic scoliosis: The method consists on the association of Method a single intramuscular rod introduced by a minimally invasive approach. The rod The protocol consisted of two evaluations of postural attitude. During the postural is proximally fixed by 3 hooks - 2 supra laminar to resist against pullout forces evaluation the patients were equipped with 62 cutaneous reflective markers and and one pedicle hook to distract – and distally fixed by two pedicle screws which were photographed in a standing position. 34 postural indices were calculated provide a good stability to the assembly and we called it “H3S2 construct”. using the MB-Ruler Pro program and 6 radiological parameters were identified. The spinal fixation levels must be selected to allow the rod to be as vertical as possible to avoid shearing forces leading to stress fractures of the rod. Rod lengthening will be performed on average every 10 months, or when the Results Cobb angle increases more than 10°. This single rod construct is certainly more The statistical tests indicated no significant difference between the two sessions fragile than a dual rod construct, but it seems to be more effective in the long term and no association between postural indices and radiological parameters. because it gives fewer complications like spontaneous fibrosis and autofusions that lead to premature failure of the method Conclusion This study reveals that postural evaluation of AIS is a reproducible method For neuromuscular scoliosis in not walking patients: We always perform a of assessment. But the postural rehabilitation applied during physiotherapy bilateral telescopic construct from C7 or T1 to the pelvis.The proximal fixation is treatment would have no influence over a period of four months. provided by two successive pediculo-supralaminar hooks claws on each side, separated by a free vertebra. The distal fixation is based on two ilio-sacral screws that provide a very solid foundation, even in the most osteoporotic bone. This construct is placed by a minimally invasive approach through two small incisions. The procedure is also performed under moderate traction and Evoqued Potential control, and is prepared by a traction period of some weeks before the surgery for deformities over 90°.

Rod lengthening in neurologic scoliosis are performed every 18 months on average, which allows to correct secondarily and progressively spinal or pelvic residual deformities thanks to an asymmetric lengthening of the rods. The construct appears to be stiff and stable allowing to avoid spinal fusion in this population of very fragile patients. In our experience this technique gives a better quality of life to the patients by improving their general and functional status and exempting them from the conservative treatment. But it should be applied early when the deformity become progressive despite conservative treatment.

68 Orthopaedica Belgica 2015 www.ob2015.org 69 I37 CONSERVATIVE TREATMENT OF IDIOPATHIC SCOLIOSIS (BRACE I38 INTERNAL FIXATION WITH OCCIPITAL HOOKS CONSTRUCT FOR AND PHYSIOTHERAPY): WHAT IS EVIDENCE BASED? OCCIPITO-CERVICAL ARTHRODESIS - RESULTS IN 14 YOUNG OR P. Mahaudens, M. Mousny SMALL CHILDREN Saint-Luc University Hospital, Brussels, Belgium J.P. Dusabe Saint-Luc University Hospital, Brussels, Belgium Idiopathic scoliosis accounts for 80% of all scoliosis. Two systematic reviews issued from Cochrane Library showed that conservative treatment was effective Internal rigid fixation for occipito-cervical using occipital hooks and cervical screws in preventing adolescent idiopathic scoliosis progression, one review for brace and/or hooks improve fusion in young or small children with bone dysplasia treatment, and the other one for physiotherapy associated to conservative and congenital abnormality. We reviewed 14 cases of children who underwent treatment. Nevertheless the scientific quality of both papers was low. occipito-cervical fusion for stenosis and instability. 13 patients had complete fusion and no failure of instrumentation and no major complications in our study. The aim of this presentation is to give an overview on the efficacy of conservative treatment (brace and physiotherapy) in adolescent idiopathic scoliosis. A We conclude that occipito-cervical fixation with hooks and screws is technically systematic search of the existing literature was conducted with the use of a feasible in very young children and it increases fusion rate and did not increase combination of keywords and text words related to “ideal age to start treatment”, complication rate. “risk of progression”, “psychological impact”, and “quality of life”.

70 Orthopaedica Belgica 2015 www.ob2015.org 71 I39 SURGICAL TREATMENT OF CERVICO-THORACIC POTT DISEASE BY I40 ANTERIOR SHOULDER DISLOCATION: RADIOGRAPHIC IMAGING KYPHOSIS CORRECTION AND CIRCUMFERENTIAL FUSION IN A 2 B. Vande Berg YEAR 9 MONTH OLD CHILD Dept. of Radiology, UCL Brussels, Belgium J. Kieffer, M. Glass, F. Hertel Kannerklinik Luxembourg, Luxemburg The aim of this presentation is to describe the radiologic signs of anterior shoulder dislocation with emphasis on radiographic imaging. Purpose Spinal tuberculosis, also called Pott disease, is rare in very young children. Few cases of patients < 3 years old treated with spinal instrumentation are reported. We describe the treatment of a 2 year 9 month old Haitian girl who had initial medical and surgical treatment in the Carribeans, requiring secondary surgery.

Methods A 16 month old Haitian girl with cervico-thoracic kyphosis was diagnosed with spinal spondilitis extending from C4 to T5, spinal cord compression and instability. Histopathology was positive for TB. She was started on 2-drug treatment consisting of Nicotibine and Rifadine and had anterior surgery consisting of C4-T5 corporectomies, a C3-T6 titanium cage and an anterior plate. 2 month later, the plate was dislocated and had to be removed. She came to Luxembourg at the age of 2 years 9 month. Neurological status on arrival was normal. Imaging by CT scan and MRI showed posterior displacement of the upper thoracic spine, cervicothoracic kyphosis with kinking of the spinal cord and posterior C7-T3 fusion. After external stabilization of the head and trunk with a halo vest, the dislocated cage was removed through a left cervicotomy. There was caseum in the distal part of the corporectomies with positive culture for Mycobacterium Tuberculosis. The gap was temporarily filled with a cement spacer and the patient was started on 4-drug treatment consisting of Myambuthol, Tebracid, Rifadine and Nicotibine. 2 days later, she had posterior surgery consisting of a C7-T3 laminoplasty, reduction of the kyphosis and C3-T6 instrumentation. 6 weeks after posterior surgery, she had an anterior C3-T6 fibular graft. The halo vest was maintained for 4 months.

Results CT scan obtained at 4 month after surgery showed anterior and posterior bone bridging and healing. Neurological status is normal. 4-drug therapy is to be continued for a total of 24 months.

Conclusions In patients with TB spondylitis, surgery is recommended if there is spinal cord compression, neurological deficit or significant spinal deformity. Despite the absence of neurological deficit in our patient, the magnitude of the deformity and the latent instability was considered an indication for surgical correction and AP fusion. Due to the number of levels fused, a significant reduction of neck mobility and cervico-thoracic spinal growth is expected.

Significance To report on surgical correction and stabilization of a cervico-thoracic kyphosis due to TB spondilitis in a very young child.

72 Orthopaedica Belgica 2015 www.ob2015.org 73 I41 WHEN IS AN OPEN ANTERIOR SHOULDER STABILIZATION I42 DECISION-MAKING FOR ANTERIOR CHRONIC SHOULDER INSTABILITY PROCEDURE INDICATED? P. Boileau, C. Duysens, M. Zumstein, J. Old, K. O’Shea O. Verborgt Dept. of Orthopaedic Surgery and Sports Traumatology, L’Archet 2 AZ Monica and University Hospital , Belgium Hospital, Nice, France

Recent studies show comparable results of arthroscopic shoulder stabilization Selection is the key to prevent recurrence following anterior instability surgery. techniques compared with the gold standard open Bankart reconstruction. Great It comprises careful pre-operative patient selection, accurate pre- and intra- technical advances and increasing surgeon experience have rendered pathology operative assessment of soft tissue and bony lesions and choosing a treatment once deemed an indication for open surgery as treatable by arthroscopic means. modality that can reliably solve the specific instability problem encountered. With this movement toward a more universal application of all-arthroscopic techniques, we might consider the following question: Is there ever a need to The analysis of treatment failures following arthroscopic Bankart repair, glenoid open? To answer this question, we must first consider normal anatomy and then and humeral bone loss as well as anterior and inferior hyperlaxity (constitutional appreciate the contribution of deranged pathoanatomy to recurrent instability or acquired) were found to significantly predispose towards recurrent instability. in each individual case. The most important issue is whether the shoulder can Patient age (<20 years), type of sport (contact or forced overhead sports) and be stabilized through a soft tissue repair or a bony procedure. The surgeon level of practice (competition) are additional factors that have been implicated in must then determine whether this is best addressed via an arthroscopic or the etiology of recurrent instability. open technique. Arthroscopy, as compared with open stabilization procedures, holds the potential benefits of decreased morbidity rates, early functional Using clinical history, examination and plain radiographs alone, the Instability rehabilitation, and improved range of motion. When a significant pathologic Severity Index Score (ISIS) can be calculated and used to assist in the lesion contributes to recurrent instability and cannot be adequately addressed as determination of the appropriate surgical procedure that will result in the lowest a result of the limitations of current arthroscopic techniques or instrumentation, probability of recurrence following surgery for anterior-inferior instability. It’s an the surgeon should choose an open technique. On the basis of this principle, easy tool that can help to guide the daily clinical practice to the good therapeutic open coracoid transfers (i.c. Latarjet procedure) have proven their efficacy in choice and the first discussion with the patient. The final therapeutic choice functional outcome and return to sports with low recurrence rates in patients needs to be planned and based on a 3DCT with or without contrast was proven with sizable glenohumeral bone defects. Other complicating issues, such as to be superior on MRI to study the bony lesions. attenuated capsule, humeral avulsion of the glenohumeral ligament lesions, cases of revision surgery, and collision or contact athletes, exist and warrant an For those patients in whom an isolated Bankart repair (and its bumper effect) is open Latarjet procedure as well. When performing these bony procedures, great insufficient, the additional procedure should depend upon the predominant type attention should be given to the surgical technique and position and fixation of the of anatomical lesion encountered: capsular deficiency and/or bony deficiency. bone block to avoid complications s.a. hardware problems, recurrent instability or secondary arthritis. Arthroscopic techniques may offer potential advantages The surgical intervention is tailored towards the underlying structural problem: addressing these issues, but especially arthroscopic Latarjet procedures remain • Bony Bankart fixation by incorporation in the Bankart repair or with the Sugaya difficult and are prone to important complications. Arthroscopic isolated bone Technique (for fracture accounting for 5 to 25% of the glenoïd surface). grafting techniques using auto – or allografts may potentially be technically • Hill-Sachs Remplissage (transfer of the posterior superior capsule and easier and may have an important value in well-defined indications. infraspinatus in the deep and engaging Hill-Sachs lesion) for patients with isolated humeral bone. In this presentation, a comprehensive review of current open and arthroscopic • Bristow-Latarjet procedure (transfer of the coracoid process through the techniques for anterior shoulder instability will be given. subscapularis muscle onto the anterior glenoid surface to recreate the bone stock and to add an anterior sling effect to the bumper effect) for patients with glenoid bone deficiency. • Trillat procedure (transfer of the coracoid process over the subscapularis to add an anterior sling effect to the bumper effect) for the patients with a deficient anterior capsule but no bone loss.

74 Orthopaedica Belgica 2015 www.ob2015.org 75 Prognostic Factors Points I43 HOW I DO AN ARTHROSCOPIC BANKART PROCEDURE? J.E. Dubuc ≤ 20 yo 2 Age at surgery St-Luc University Hospital, Brussels, Belgium > 20 yo 0 Introduction Competition 2 A Bankart lesion is an injury of the anterior (inferior) glenoid labrum of the shoulder Degree of sport practice Questionnaire Recreational or non 0 that results from an anterior shoulder dislocation or subluxation. This can lead to sports recurrence or apprehension of positioning the shoulder in an overhead throwing Contact or forced 1 position. A Bankart lesion is often accompanied by a Hill-Sachs lesion. The arthroscopic procedure consists of three or four anchors placed along the ABD-ER Type of sports entire length of the traumatized inferior glenohumeral ligament (IGHL). Other 0 Several factors limit arthroscopic procedures and should be carefully evaluated Shoulder 1 preoperatively: • Significant bone changes resulting from dislocation recurrence: an anterior hyperlaxity Exam Shoulder hyperlaxity glenoid rim fracture, erosion loss from multiple recurrences and an impression Normal laxity 0 defect on the posterior aspect of the humeral head (Hill-Sachs lesion) In external rotation 2 • Patients who fail prior surgery due to an atraumatic event Hill-Sachs on AP X-ray The Instability Shoulder Index Score (ISIS) is used to predict the success of Not visible in ER 0 arthroscopic Bankart repair. AP X-ray Glenoid loss of contour Loss of contour 2 Rim erosion from chronic recurrent dislocations may require a combination of on soft-tissue reattachment and coracoid grafting.

X-ray No lesion 0 Surgical Pearls Total 10 pts The pearls for this procedure are • An examination under anesthesia includes range of motion and translation testing. Engagement of the Hill-Sachs lesion and the damaged glenoid rim is The ISIS score the position of the arm and degree of abduction to recreate the dislocation. • The patient is positioned in the lateral decubitus position. • A posterior viewing portal is created 2 cm from the inferior border of the spine of the scapula and lateral margin of the acromion. The two anterior portals are created between the acromion and coracoid, entering in the rotator interval space. The superior portal is useful to visualize the anatomy of the damaged structures. The working anteroinferior portal is designed lateral to the coracoid, providing access to the inferior glenoid articular margin. • Soft tissue mobilization: The inferior labrum and ligaments are mobilized and separated from the subscapularis. Clear visualization of the subscapularis through the defect is a good indicator of this dissection. • Glenoid rim preparation consists of debriding and abrading the glenoid neck. • A series of bone anchors is applied to the anteroinferior and inferior rim of A la carte” arthroscopic management of recurrent anterior instability: our treatment algorithm is the glenoid, depending on the extent of the labral detachment. based on: 1) determination of risk factors for failures after isolated Bankart repair with the help of the • The first anterior anchor is placed approximately at 5 o’clock on a right ISIS score and 2) selection of the additional procedure to perform according to the predominant (soft shoulder. This is an important strategic anchor to reestablish the resting tissue and/or bony) lesion encountered. position of the humeral head. A second anterior anchor is placed 1 cm (@ = arthroscopic) superiorly. • The most superior anchor of the anterior repair is at the superior margin of the glenoid bone indentation or fovea.

76 Orthopaedica Belgica 2015 www.ob2015.org 77 Surgical Controversy I44 HOW I PERFORM A BONE BLOCK ARTHROSCOPIC PROCEDURE? Closure of the rotator interval has been controversial. In repairs of collision T. Van Isacker athletes, this interval is closed for additional restraint to anterior translation. Orthopaedics Dept., AZ Sint-Lucas, Brugge, Belgium Overhead-throwing athletes may lose maximum external rotation with interval closure. The bone block procedure I perform arthroscopically is the arthroscopic Latarjet procedure as described by Laurent Lafosse in 2007. Postoperative Care We performed the first arthroscopic Latarjet procedure in Belgium in December The postoperative period begins with a brace that positions the shoulder in 2008. Although there was a long and steep learning curve, the technique is safe internal rotation.Time within this brace ranges from 3 to 4 weeks. Patients are and reproducible. started on scapular strengthening, pendulums, and grip strength. The purpose of this presentation is to enlighten the different aspects and crucial Gradual mobilization and return to sports and activities are customized to the steps of the technique. patient’s healing response and the desired activity. Return to activities is 4 to 6 The role of the anesthesiologist, scrub nurse and assistant is crucial. months. The procedure is divided in 5 steps: Conclusion • Preparation of the glenoid neck Arthroscopy is a good technique for treating carefully selected patients (ISIS • Split of the subscapularis lower than or equal to three ) and to stabilize the glenohumeral joint .Attention to • Harvesting of the coracoïd detail is critical in patient selection, technique, and postoperative management. • Transfer of the coracoïd through the subscapularis Surgeons need to be familiar with multiple procedures to correct the different • Fixation of the coracoid to the scapular neck problems that may develop following shoulder dislocation. With careful selection of patients for an arthroscopic technique, the surgical time, Bibliography correct positioning of the coracoid and complication rate is comparable to the 1. Balg F, Boileau P The instability severity index score. A simple pre-operative score to select open technique. patients for arthroscopic or open shoulder stabilisation. J Bone Joint Surg Br. 2007 89(11):1470-7. 2. Abrams JS, Bradley JP, Angelo RL, Burks R. Arthroscopic management of shoulder instabilities: anterior, posterior, and multidirectional. Instr Course Lect. 2010;59:141-55. 3. Bessière C1, Trojani C, Carles M, Mehta SS, Boileau P. Clin Orthop Relat Res. 2014 Aug;472(8):2345-51. The open latarjet procedure is more reliable in terms of shoulder stability than arthroscopic bankart repair.

78 Orthopaedica Belgica 2015 www.ob2015.org 79 I45 A GUIDED SURGICAL APPROACH AND NOVEL FIXATION METHOD FOR ARTHROSCOPIC LATARJET P. Boileau, P. Gendre, M. Baba, C.E. Thélu, T. Baring, J.F. Gonzalez, C. Trojani Dept. of Orthopaedic Surgery and Sports Traumatology, L’Archet 2 Hospital, Nice, France

Background Most of the complications of the Latarjet procedure are related to the bone block positioning and use of screws. The purpose of this study was to evaluate if an arthroscopic Latarjet guiding system improves accuracy of bone block positioning and if suture button fixation could be an alternative to screw fixation in allowing bone block healing and avoiding complications.

Materials and Methods Seventy-six patients (mean age, 27 years) underwent an arthroscopic Latarjet procedure with a guided surgical approach and suture button fixation. Bone Latarjet procedure with cortical button fixation. The coracoid process is transferred and fixed on the graft union and positioning accuracy were assessed by postoperative computed anterior neck of the scapula with 2 cortical buttons and a 4-strand suture. The anterior (coracoid) tomography imaging. Clinical examinations were performed at each visit. button has a pegged eyelet (to avoid cutting the bone with the suture) and is placed first; the posterior (glenoid) button has 2 holes (or a single hole) and is placed after having pulled the suture in the back of the shoulder. Results At a mean of 14 months (range, 6-24 months) postoperatively, 75 of 76 patients had a stable shoulder. No neurologic complications were observed; no patients have required further surgery. The coracoid graft was positioned strictly tangential to the glenoid surface in 96% of the cases and below the equator in 93%. The coracoid graft healed in 69 patients (91%).

Conclusions A guided surgical approach optimizes graft positioning accuracy. Suture button fixation can be an alternative to screw fixation, obtaining an excellent rate of bone union. Neurologic and hardware complications, classically reported with screw fixation, have not been observed with this guided technique and novel fixation method.

80 Orthopaedica Belgica 2015 www.ob2015.org 81 I46 PAUL-MARIE GRAMMONT’S REVERSE TOTAL SHOULDER The first Dijon implantation occurred at the beginning of 1986. By subsequent PROSTHESIS improvements came in 1991, a first generation of modular prosthesis so-called E. Baulot DELTA III made of 5 parts: glenoid baseplate fixed by 2 polar divergent screws and Orthopaedic and Traumatology Dept., Dijon University Hospital, Dijon, 2 equatorial screws, screwed hemi-spheric glenoidal component, polyethylene France cup, metaphysis and shaft of the humerus. This prosthesis is the “mother” of all current prostheses. The response will be lukewarm; however regarding This truly odyssey of Dijon academic surgeon’s invention, Paul Grammont, the quality of the functional results obtained on active mobility in particular on started from unanimous recognition at the end of 1970 that it is impossible to anterior flexion, the diffusion becomes French then quickly European. Finally, obtain good functional results after shoulder arthroplasty for osteoarthritis with FDA approval in United States in 2004 leads to worldwide diffusion. The analysis massive rotator cuff tear. Charles Neer, himself, described this pathology as « of first series showed the emergence of a frequent and specific complication, limited goals surgery ». Paul Grammont explained shoulder mechanical failure scapular notching that might compromise glenoid fixation at mid-term. Solutions of modern man from the comparative anatomy. He analyzed the acquisition of will be quickly proposed to decrease the occurrence and significance. Currently, human raised position which by releasing the shoulder develops new functional about 60% of implanted shoulder prostheses are reverse with an increase competencies. However, they exceed their real organic possibilities with a major perspective of reverse implant of 15% per year. change: relative atrophy of supraspinatus coupled with lateralization of acromion reinforcing the middle deltoid. This creates a real mechanical imbalance to the This original and major discovery of a French surgeon, developed in partnership detriment of the rotator cuff with system’s mechanical failure as consequence. with the French laboratory Medinov, thus at 100% French, allowed to introduce an effective solution to address an issue remained open until now. Then, the original mechanical concept necessary for the intrinsic balance of middle deltoid was demonstrated with pure mathematical theoretical approach. This work directed by P. Grammont was published in J. Bourgon and P. Pelzer engineers final studies report (Dijon University, E. C. M. A. of Lyon, June 1981) entitled “Study of total shoulder prosthesis mechanical model. Prototype creation”.

I quote: “... this leads to the following principle: medialize the center of rotation of the scapular-humeral joint, thus the increase in lever arm of deltoid compensates supraspinatus muscle’s activity loss. Therefore, we are seeking to lift the mobile joint toward the scapula, but with no change of humeral position relative to scapula. Indeed, if in the same time the humerus is interiorized, the deltoid lever arm might be retained and not increased…but keeping the idea of internal rotation centre, the passing of humerus under the edge of acromion will be even more difficult. We will need to lower first the rotation centre.”

The innovative mechanical concept of MEDIALIZATION was born, defining the specifications of a new prosthesis with reverse forms. The break with anatomy is total, sudden; this is definitively a “revolution”. The first prototype has been manufactured in 1985 and called TROMPETTE. Consisted of polyethylene humeral part and glenoid component representing two-third of 44mm diameter sphere, its fixed and unique medialized rotation centre is projected on glenoid plan. This prototype was tested and approved on Strasser-type experimental model by X.Deries in « Biomecanical approach on deltoid strengths stir for modification of shoulder prosthesis rotation centre in abduction. (Postgraduate degree Paris XI University, 1986). 82 Orthopaedica Belgica 2015 www.ob2015.org 83 I47 REVERSED TOTAL SHOULDER ARTHROPLASTY FOR FRACTURE I48 REVERSE AND NOTCHING: FREQUENCY? THREAT? HOW TO AVOID B. Berghs THIS? Orthoclinic, AZ St Jan AV Brugge-Oostende, Belgium L. De Wilde Dept. of Orthopaedics, Shoulder and Elbow Surgery, Ghent University, The incidence of proximal humeral fractures is steadily increasing, ranking 3rd in Ghent, Belgium fragility fractures. Surgical treatment has always been a challenge and covered with complications. Background and Purpose Despite good clinical results with the reverse total shoulder arthroplasty, As experience with a reversed total shoulder arthroplasty has grown, indications inferior scapular notching remains a concern. We evaluated the frequency of its occurrence. We also evaluated if this phenomenon has a clinical impact. Finally expanded and complex proximal humerus fractures in the elderly are now very we analysed 6 different solutions to overcome the problem of scapular notching. often treated with a reversed arthroplasty in Belgium. Despite its widespread patients’ subjective impression on their shoulders’ stability is not correlating with use for this indication, literature is still limited and has a low level of evidence. radiological signs of infraglenoidal scapular notching. Further, comparative studies with the traditional hemiarthroplasty are scarce and all but one retrospective. Methods We performed a literature search on the frequency of scapular notching and its The theoretical added value of a reversed arthroplasty is clear: functional results clinical impact. Than an average and a “worst case scenario” shape in A-P view do not depend on the rotator cuff. However, a reversed arthroplasty has its own in a 2-D computer model of a scapula was created, using data from 200 “normal” complications and its price. scapulae, so that the position of the glenoid and humeral component could be changed as well as design features such as depth of the polyethylene insert, the size of glenosphere, the position of the center of rotation, and downward The indications, contraindications and surgical procedure are discussed. glenoid inclination. The model calculated the maximum adduction (notch angle) in the scapular plane when the cup of the humeral component was in conflict For now, reversed total shoulder arthroplasty appears a valuable alternative for with the scapula. hemiarthroplasty and results are promising. Prospective studies are necessary to justify its explosive popularity for this indication. Results Notching occurred in 68% of cases. It appeared early, but its later evolution was variable. Notching was associated with follow-up, strength, passive and active elevation, humeral radiolucent lines, and glenoid lucent lines. It also correlated with a higher rate in patients with preoperative superior erosion. A change in humeral neck shaft inclination from 155° to 145° gave a 10° gain in notch angle. A change in cup depth from 8 mm to 5 mm gave a gain of 12°. With no inferior prosthetic overhang, a lateralization of the center of rotation from 0 mm to 5 mm gained 16°. With an inferior overhang of only 1 mm, no effect of lateralizing the center of rotation was noted. Downward glenoid inclination of 0º to 10º gained 10°. A change in glenosphere radius from 18 mm to 21 mm gained 31° due to the inferior overhang created by the increase in glenosphere. A prosthetic overhang to the bone from 0 mm to 5 mm gained 39°.

Conclusions Scapular notching is frequent, generally progresses, and is associated with deterioration of some clinical parameters and radiolucent lines. The preoperative pattern of glenoid erosion is of particular importance due to its influence on the surgeon’s glenoid preparation and base-plate positioning. It is crucial to avoid cranial position and superior tilt. To prevent scapular notching theoretically of all 6 solutions tested, the prosthetic overhang created the biggest gain in notch angle and this should be considered when designing the reverse arthroplasty and defining optimal surgical technique. 84 Orthopaedica Belgica 2015 www.ob2015.org 85 I49 HOW DO I MOBILIZE MY PATIENTS AFTER A REVERSE SHOULDER I50 THE CLEER PATIENT – DO WE HAVE A CLEAR ANSWER ARTHROPLASTY? RESULTS OF REVERSE ARTHROPLASTY WITH MODIFIED L’EPISCOPO E. Lejeune, G. Opsomer TRANSFER Service d’orthopédie et traumatologie, Clinique Saint-Luc, Bouge, Namur, P. Boileau, M.O. Gauci, W. McClelland, C. Bessière, C.E. Thélu, Belgium A. Rumian, Y. Roussanne Dept. of Orthopaedic Surgery and Sports Traumatology, L’Archet 2 Goals of the rehab after RSA Hospital, Nice, France • Avoid stiffness and muscle strengthening • Soft tissue healing, especially the subscapularis Introduction To evaluate subjective and objective results of reverse shoulder arthroplasty Rehab RSA vs TSA (RSA) combined with transfer of latissimus dorsi and teres major tendons • Rotator cuff is absent or minimally functionnal (modified L’Episcopo transfer) in a large cohort, and determine if post-operative • Inherent instability due to the design improvements were maintained over time. • Superior approach or deltopectoral approach Methods The key: communication between the surgeon and the physiotherapist Prospective cohort study. Between February 2004 – March 2013, 59 consecutive patients presented to our clinic with a combined loss of active elevation and 3 keys for RSA rehabilitation: external rotation (CLEER). They were treated with a combined RSA and modified 1. Joint protection L’Episcopo transfer. Patients were prospectively followed-up on a yearly basis. 2. Deltoid Function Clinical and radiographic evaluation was obtained in all patients at each visit. 3. ROM and Functional expectations 2 was unable to follow up and 1 patient dead. Follow-up averaged 32 +/- 25 months. 5 patients presented a massive cuff tear, 36 a cuff tear arthropathy, 2 Conclusion fracture sequelae, 4 had a a failed arthroplasty and 9 a failed cuff repear. • Rehabilitation after RSA is different than TSA • The function of deltoid is the corner stone of the rehab Results • Patient, Physical Therapist and Surgeon should work together Two patients sustained traumatic transfer rupture (1 instability and 1 fracture under the prosthesis. They were excluded from functional analysis, leaving 54 total patients (31 female, 23 male). Age at surgery was 70 years (range: 52-84). SSV was significantly improved from 29% preoperatively to 72% postoperatively. Forward flexion improved by an average of 53° and external rotation improved by 28° (-30 to 70°). ADLER and adjusted Constant scores improved respectively from 9 pre-operatively to 25 post-operatively, and a mean of 44% to 88% at most recent follow-up. Improvements were maintained over long-term follow-up. Apart from one of the two patients who sustained a fracture, all patients were satisfied or very satisfied with their surgical result at most recent follow-up. 49 patients were very satisfied ou satisfied, 5 patients were disappointed.

Conclusion Combined RSA with modified L’Episcopo transfer is an effective procedure for restoring forward elevation and external rotation in patients presenting with a combined deficit. Subjective and objective improvements are realized soon after surgery and are maintained with time.

86 Orthopaedica Belgica 2015 www.ob2015.org 87 I51 BONE TUMOUR AT THE SHOULDER: WHICH FUNCTION AFTERWARDS? TWO BELGIAN SERIES: GHENT SERIES L. De Wilde Dept. of Orthopaedics, Shoulder and Elbow Surgery, Ghent University, Ghent, Belgium

Background Normal function of the upper limb is seldom restored after limb-sparing surgery for tumors of the proximal humerus. The literature suggests superior shoulder Illustration of the principals of the modified L’Episcopo transfer. The latissimus dorsi (LD) and teres function is achieved in the short term with reverse total shoulder arthroplasty major (TM) are changed from internal rotators of the humerus (A) to external rotators of the humerus compared to other techniques when performed for conditions with rotator cuff (B) by adjusting their point of insertion. This replaces the external rotation function lost by the deficient infraspinatus and teres minor. deficiency. It is unclear whether this superiority is maintained when reverse total shoulder arthroplasty is performed for tumors.

Questions/Purposes When performed for tumors, we determined whether reverse total shoulder arthroplasty restores function and improves motion, the complications associated with the surgery, and whether reverse total shoulder arthroplasty with autologous grafting is associated with bone resorption.

Patients and Methods We retrospectively reviewed 14 patients who had undergone reverse total shoulder arthroplasty for tumors of the proximal humerus. Four patients died, leaving nine patients for review. The surviving patients were evaluated clinically and radiographically. The minimum follow-up was 0.6 years (mean, 7.7 years; range, 0.6-12 years).

Illustration of the combined effect of the reverse shoulder arthroplasty with latissimus dorsi / teres major transfer. Note the restoration of vertical balance (forward elevation, abduction) provided by Results the deltoid and restoration of horizontal balance (external rotation) provided by the tendon transfer. At last follow-up, mean active abduction was 157° and mean functional Constant- Murley score was 76%. One patient had a deep infection and one developed a loose prosthesis; both were treated with single-stage exchange. At last follow-up, both patients had reasonable function without evidence of infection or loosening. Radiographic graft resorption was seen in all but one patient.

Conclusions Our observations suggest, at medium-term follow-up, reverse total shoulder arthroplasty is a reasonable option for tumors of the proximal humerus. It has low morbidity, restores a mean active abduction of 157°, and limits the impairment of activities of daily living.

88 Orthopaedica Belgica 2015 www.ob2015.org 89 I52 BONE TUMOUR AT THE SHOULDER: WHICH FUNCTION I53 REVISION SURGERY OF REVERSE SHOULDER ARTHROPLASTY AFTERWARDS? P. Boileau, P. Gendre, T. D’Ollone, C. Bessiere, T. Baring, N. Holzer TWO BELGIAN SERIES: BRUSSELS SERIES Department of Orthopaedics and Sports Traumatology, L’Archet 2 T. Schubert Hospital, Nice, France Dept. Orthopaedics and Traumatology, Cliniques universitaires Saint-Luc, Brussels, Belgium Aim To evaluate reasons for failure in reverse shoulder arthroplasty (RSA) and the Primary bone tumours of the proximal humerus are rare entities and they are of outcomes of revision RSA. considerable challenge should the shoulder be reconstructed. While removing the tumour is the primary target of the treatment, a satisfactory Methods function of the shoulder is clearly the main secondary outcome. Between 1993 and 2012, 47 patients with RSA had revision surgery. Clinical and radiologic examinations performed preoperatively and at 3 months, 6 months, From 1987 up to 2006, the reconstruction was based on the anatomy, using an and then annually post-operatively were analyzed retrospectively. Patients were osteochondral allograft and its tendons. Bone was fixed with a plate or a nail. reviewed with a minimum one-year follow-up. However, the availability of a functional prosthesis such as the reverse one has changed our mind and we now use the reverse prosthesis (RP) in combination Results with an allograft if necessary. Active motion and in particular elevation seemed The most common causes for RSA revision were prosthetic instability (37%); more satisfactory. Therefore, we assessed the mobility and the function of our humeral loosening, derotation, or fracture (27%); and infection (24%). Only patients using the Musculoskeletal Society Score (MSTS) and Disabilities of the 3 patients (6%) had to be reoperated on for glenoid loosening and 3 patients Arm, Shoulder and Hand (DASH) questionnaire. for other case. More than 1 re-intervention was performed in 13 patients (28%) because of recurrence of the same complication or appearance of a Between 1987 and 2014, 18 primary bone tumours of the proximal humerus new complication. Underestimation of humeral shortening and excessive were treated at the Cliniques Universitaires saint-Luc in Brussels. Diagnosis medialization were common causes of recurrent prosthetic instability. Proximal was chondrosarcoma (CS) in 6 cases, osteosarcoma (OS) in 11 cases and 1 humeral bone loss was found to be a cause for humeral loosening or derotation. neurofibrosarcoma. Of our 18 patients, 4 died of metastatic disease and one Previous surgery was found as a potential cause of low-grade infection. At a did not participate to our review. Between 1987 and 2006, 8 patients received mean follow-up of 41 months, 42 patients (89%) had retained the RSA whereas 2 a massive osteochondral allograft, 3 of whom died of the disease subsequently. patients (4%) had undergone conversion to humeral hemiarthroplasty and 3 (6%) Ten patients were treated using a reverse prosthesis between 2006 and 2014. to a resection arthroplasty. The mean Constant score in patients who retained the RSA increased from 21 points before revision to 57 points at last follow-up Patients with a prosthesis had a significantly better elevation than the ones (P < .05). reconstructed with a massive osteochondral allograft (134 ± 36° vs. 47 ± 26° for RP vs. allograft, respectively, p<0.05). Deficit of external rotation when compared Conclusions to the contralateral side was found to be similar in both groups. MSTS score Even if revision may lead to several procedures in the same patient, preservation was significantly better in the prosthetic group (23 ± 2.5 vs. 18 ± 2 for the RP vs. or replacement of the RSA is largely possible, allowing for a functional shoulder. allograft group, respectively, p<0.05). Seven patients in the prosthesis group and Full-length scaled radiographs of both humeri are recommended to properly four of the allograft group sent the DASH questionnaire back and adequately assess humeral shortening and excessive medialization before revision. filled. No significant differences in these outcomes were observed.

Conclusion Clinical examination and MSTS score concluded to a better active motion when reconstructing the shoulder with a reverse prosthesis.

90 Orthopaedica Belgica 2015 www.ob2015.org 91 I54 TIPS AND TRICKS IN REVERSE ARTHROPLASTY REVISION Indeed, to obtain a stable glenoid construction, bulky-allografts must be used to F. Mulpas, with the collaboration of the «Shoulder Commission» restore this anatomical structure more effectively. Dept. of Orthopaedics, Clinique Edith Cavel, Brussels, Belgium Loosening of the humeral component is very low (< 2%). However, there are a number of indications for humeral component stem removal (instability, access RSA has evolved to become the dominant option for patients who have substantial of the glenoid side) and this is associated with significant risk of fracture and shoulder pain coupled with an irreparable rotator cuff and glenohumeral arthritis. bone loss. The indications for RSA have expanded beyond those for rotator cuff arthropathy. These surgical indications now include failed shoulder hemiarthroplasty or total So, in this presentation, based upon medical literature and some clinical cases, shoulder arthroplasty, failed treatments of proximal humeral fractures, treatments we will try to expose the «Surgical Tips and Tricks» of these different challenging for 3-part or 4-part proximal humeral fractures associated with greater tuberosity points in RSA revision. osteopenia, and selected patients with massive irreparable rotator cuff tears associated with pain and shoulder dysfunction. RSA has truly ushered in a new era of shoulder surgery and, when the arthroplasty fails, revision remains however a technical challenge with many unanswered questions.

The reported complication rates of RSA in medical literature have been reported from 0% to 68%. The main indication for early revision is infection and instability, 2.4% to 31%. Limited medical literature is available regarding the management of deep infection in patients with RSA. Revision RSA involved increased bone loss concerns over traditional TSA (insufficient glenoid vault and proximal humerus for reimplantation of a baseplate and humeral component).

A recent study (Beekman, 2015; 11 revision RSA in one-stage; 10/11 free of infection at 24 months), suggests treating deep infection with retain components in the initial management by debridement, removal of the modular components and reserved resection arthroplasty if eradication of infection was unsuccessful. Regarding the instability, P. Boileau has published algorhythms describing strategy for the treatment of the unstable RSA. In the same context, A. Laderman, P. Boileau, F. Farron and G. Walch published a study about the effect of humeral lateralization and variation of neck-shaft angle, on the range of motion (ROM) and scapular impingement with different stem design. This recent study is really helpful to understand the better choice of the optimal design in RSA revision to obtain the optimal result in motion range and stability of the implant.

The most frequent RSA complications are to be found on the glenoid side (notching 35% (Zumstein)) baseplate-glenosphere malposition/loosening with the great difficulty to restore bone insufficiency. Effectively rebuilding large cavitary lesions in this small bone volume of the scapula is really technically challenging.

92 Orthopaedica Belgica 2015 www.ob2015.org 93 I55 CAN RESEARCH AND INNOVATION IN ORTHOPAEDIC SURGERY It means that it is necessary to create in health care facilities and research CHANGE OUR DAILY LIFE? laboratories new information systems whose role is not only to ensure the access P. Merloz and storage to information but also to provide data treatment. This development Clinique Universitaire d’Orthopédie Traumatologie, Université Joseph is a direct result of the evolution of medicine to a more scientific medicine, safer Fourrier, CHU A. Michallon, Grenoble, France and more personalized requiring diagnosis or therapeutic decisions based on well-validated data. New technologies and information technology tools Like all medical specialties, Orthopaedics is actively involved in the advances constitute a valuable reinforcement, not only to carry out more reliable and of medicine. During the last thirty years, patients have benefited from a number reproducible treatments, but also to better organize them. This is a real challenge of innovations. Innovation is a difficult word which has the distinction of being for both technical and clinical point of view for the well being of the patient. an intransitive verb. Innovation is an abstract action which involves nothing. We can define innovation as follows: an innovation is a significant improvement and even radical, not the reverse. There are many types of innovation: Product innovation, process, marketing and organization. Product innovation is known by orthopedic surgeons and in this domain we can make a difference between breaking innovations [e.g. digital photography versus film photography] and continuity innovation that proceed by gradual and successive improvements of current technology performance. Modern Orthopaedics lives of these two components (breaking and continuity innovation).

New technologies have made an important and sometimes dominant role in the field of health care, because they are the result of advances and discoveries made since the beginning of the twentieth century. We must now face to a major challenge: how to combine high level care, increase in health cost, increase in aging population in Western countries with a low economic growth environment.

The new technologies in Medicine and Orthopaedic surgery have many facets and they can be divided into seven main chapters: modeling and simulation in medicine; signals and image processing in medicine; medical information systems and database; sensors, clothing, housing and intelligent networks in health sciences; modeling analysis and tools for disabilities; learning and assistance to surgical procedures and e-Health. We must add to these chapters the one related to the tissue bioengineering and implants for joint replacement or osteosynthesis. A true loop can be created around the patient, from diagnosis to the treatment step and to the ascertainment of clinical outcomes. The methods and modeling tools are still to be developed to address all issues, especially the specific domain of health. We are faced to a great challenge that can be addressed through close collaboration between several disciplines, such as engineering sciences, mathematics, signal and image processing, with physiologists, biologists and clinicians teams.

94 Orthopaedica Belgica 2015 www.ob2015.org 95 I56 3D PRINTING OF CERAMICS: CURRENT PAST AND FUTURE IN I57 GUIDES AND SPECIFIC IMPLANTS FOR COMPLEX ACETABULAR MEDICAL APPLICATIONS RECONSTRUCTIONS C. Engel K. Govaers, J. Robberecht Xilloc Medical B.V., Maastricht, The Netherlands Dept. of Orthopaedic Surgery, Sint Blasius Hospital, Dendermonde, Belgium The possibility to create patient-specific medical devices derived from real human scan data specific to each patient is a reality that can only be offered by We describe our early experience with 3D printing in complex revision and 3D Printing technology. The need for patient-specific implants becomes not only primaty total Hip arthroplasty. necessary for cases of trauma, tumours or birth defects, but since every human and its anatomy are different, the implant has to be adapted to the patient’s Revision THA anatomy as well and not the other way around. Acetabular component revision surgery is a challenging procedure, especially when significant bone loss is present. The modified custom triflange acetabular Ceramics such as hydroxyapatite (HAP) and tri-calcium phosphate (TCP) or a component has recently joined the list of available treatment options. Based on combination of both that are currently being developed and industrially used a preoperative Ct scan with 3D reconstruction a plastic model of the pelvis is for spinal and cranio-maxillo-facial implants are biodegradable and bioactive. printed using 3D printing technology. Since those can be produced through 3D Printing technologies, they have a Based on this model a preliminary custom made triflange cup is designed in big advantage compared to ceramic foams. 3D Printing allows a layer by layer close collaboration with the orthopaedic surgeon. This model takes into account fabrication, thereby making the creation of foams with interconnected pores the quality of the remaining host bone. The custom reconstruction cage bridges possible. Those geometries are proven to be more efficient for the Osseo- the defect of the posterior column of the pelvis and is able to correct for pelvic integration and thus the acceptance of the implant. discontinuity. After surgeon approval the final titanium component is printed. Together with this implant comes a custom-made drill guide to assure correct Currently, more than 10,000 inter-vertebral cages in HAP are produced every screw positioning and a plastic trial implant for intraoperative preparation of the year as an example. Compared to metals, ceramics remain very brittle however host bone. All this components are autoclavable. and cannot be used for load bearing applications. There have been no re-revisions in our first 6 patients with severe Paprosky 3 B acetabular defects.

Primary THA Total hip arthroplasty in developmental dysplasia of the hip remains challenging. Complex reconstructive procedures are described in cases of severe acetabular deficiency of the hip. Mostly, autologous femoral head grafts are the technique of choice to restore acetabular anatomy and to obtain optimal coverage of the acetabular cup. Long-term benefits of this technique remains controversial with studies reporting high rates of graft resorption, collapse and non-union. In some cases, highly dysplastic hips require an alternative technique, because of the inability to use femoral head autografts. A custom- made acetabular augment in order to restore this acetabular anatomy could be solving.

Methods We present 5 cases (3 patients, 2 bilateral) of primary total hip arthroplasty in a severe dysplastic hip (Crowe type III and IV), using a patient specific, CT- based acetabular augment. This augment is a metal implant with a trabecular surface to restore the acetabular anatomy and to achieve excellent coverage of the acetabular cup. A custom-made 3D-printed drilling jig was used for optimal screw positioning. Follow-up was clinical and radiological. Mean follow-up time was 13.6 months. 96 Orthopaedica Belgica 2015 www.ob2015.org 97 Results I58 ADDITIVE MANUFACTURING: A NEW TECHNOLOGY FOR We found a satisfactory clinical short-term outcome with restoring of full weight MANUFACTURING PATIENT-SPECIFIC INSTRUMENTS: HISTORY AND bearing. Radiological follow-up showed outstanding augment and screw PRACTICAL EXAMPLES positioning and cup coverage. No short-term complications were reported. L. Paul 3D-Side, Louvain-la-Neuve, Belgium Conclusion The use of custom-made acetabular augments in total hip arthroplasties in highly Patient-Specific Instruments have revolutionized the computer assistances in dysplastic hips is a promising technique. The use of 3D- printed instruments and orthopedic surgery. They progressively replaced the optical navigation systems augments simplifies this challenging acetabular reconstructions. from the early 2010’s to assist the surgeons during total knee arthroplasties. Nevertheless, they have been invented much earlier in the middle of 1990’s for rare and difficult surgeries. Manufactured by subtraction technology (milling) at its beginning, these instruments have not been widely accepted. Their resurgence came from the manufacturing process that has evolved toward material addition e.g. the so-called “3D printing” technology. This latter has known a tremendous growing these years so that it is now considered as the third industrial revolution. The technology has opened new possibilities to treat individual patients. This lecture reminds the history of patient-specific instruments, the manufacturing evolution, and their slow acceptation in the operative room. Emphasis will be put on the preoperative planning that is the crucial task to obtain accurate and useful instrument. A brief report on the controversy about their claimed accuracy and usefulness will be discussed. Finally, innovative applications will be exposed showing the high potential Patient-Specific Instruments can bring.

98 Orthopaedica Belgica 2015 www.ob2015.org 99 I59 DID GUIDES CHANGE MY PRACTICE ? A FRENCH EXPERIENCE • Bone section, mainly were a dorsal to ventral section is carried out where F. Gouin a bone is deep (S1 for example), is dramatically secured by PSI. Thus, the University Hospital of Nantes, France temptation is high to reduce the anterior approach. Higher sacral resection have been done with PSI without anterior approach or associate to a less Pelvis bone tumor resection for bone tumor and reconstruction is a challenging invasive anterior approach (robotic anterior sacral dissection). surgical procedure. This stepwise procedure includes – accurate surgical • As clinical experience (pelvis or elsewhere) is in adequacy to preclinical planning based on high quality imaging and multidisciplinary staging of results of the accuracy of PSI, we planned closer margins than we used to the tumor – patient preparation to a disabling surgery – per operative without PSI for at least 2 cases in the aim to save neurological root. One was replication of planned bone section – long lasting and sometime stressful a failure. At the moment, one must keep in mind that PSI is a tool that aims to surgery – management of high rate of post operative complication – poor improve validated procedure, but not to change the standards. functional and oncologic results. Conclusion Based on our personal experience of Patient Specific Instrumentation (PSI) PSI is a very attractive tool to ease and to improve results of pelvic bone surgery. for pelvis oncologic surgery and some other cases of French colleagues, we Nevertheless, caution is needed before changing one’s practice: the tool as to examine how the use of PSI could have changed my practice. be assessed accurately to define its true benefit for patients and its potential interest in reducing margins and surgical approaches. We used PSI for surgical treatment of 13 patients, suffering of primary bone tumor that required pelvic bone resection. Patients requiring a bone section of posterior part of iliac bone and vertical sacral section (from sciatic notch to sacral bone) were our major indication for PSI.

Clear margins (R0) were obtained for 11 patients, R2 for one patients and R1 in soft tissues for one. The error in planned safe margin averaged 0.8mm (0.1 to 3.4mm).

Per operative time needed for adequate position to the jib was less than 5 minutes in all cases. Jjb were used for both bone section and reconstruction for two patients. At the moment, 1 patient had a local recurrence around femoral vessels (the one who was soft tissues R1) and 1 patient had an early local and distant massive recurrence (he died 5 months after surgery).

Did this experience change my practice? • The use of PSI required to undergo the preoperative planning at least 3 weeks before the surgery: despite it could be the rule with as well without PSI, early planning is a safe practice: it let time to complete inadequate imaging, to prepare earlier patients to unavoidable sequelaes of this surgery, to order sophisticated or custom made reconstruction device. • It takes 30 minutes to 1 hour to delimitate the tumor / to validate engineer proposal. In fact it takes no more 15 minutes extra time on your office: delimitation of the tumor should be done for each procedure, as it gives you the best approach to plan the surgery, to address some troublesome extension (intra articular / perivascular…). This step, required efficient tools to communicate with the engineer.

100 Orthopaedica Belgica 2015 www.ob2015.org 101 I60 DID GUIDES CHANGE MY PRACTICE ? A BELGIAN EXPERIENCE I61 PRODUCT INNOVATIONS IN SURGERY AS AN OUTCOME P.L. Docquier1, L. Paul2, K. Tran Duy2 IMPROVEMENT FOR SURGEONS IN DAILY PRACTICE 1Paediatric Orthopaedic Surgery, Cliniques Universitaires Saint-Luc, M. Hessmann Brussels; 23D-Side, Louvain-la-Neuve, Belgium Klinik für Unfallchirurgie und Orthopädie, Klinikum Fulda, Fulda, Germany Surgical guides or patient specific instruments (PSI) are instruments that are specific to the patient and created on the basis of the CT-scanner or the MRI Techniques in operative fracture management developed rapidly throughout of the patient. They are placed at the surface of the bone and have only one the last 20 years. Although former generations of nails and plates did provide possible location. They allow positioning wires or guiding a sawblade. adequate stability in many fractures, these implants clearly had limitations from PSI ‘s have been developed in our research laboratory to improve accuracy in both the biological and the biomechanical point of view. New biology-preserving malignant tumor resection surgery and to improve safety in safe margins. We approaches and indirect reduction techniques reduce the risk of specific have observed a very important accuracy gain by using the PSI. Now PSI are complications like nonunion and infections. routinely used in oncological surgery. New implants help the surgeon in achieving excellent stability and maintaining optimal reduction in dia- and metaphyseal fractures as well as in articular injuries. Other indications have rapidly been found: PSI for complex tridimensional Adequate stability is the prerequisite for an early functional aftertreatment and osteotomy, for rotational osteotomy and for tarsal coalition resection. for a good functional end result. On the other hand, orthopaedic trauma surgeons are confronted today with Advantages of using PSI is the time sparing, the accuracy gain and no need for changing challenges. Fractures in the elderly e.g. are a rather new but rapidly peroperative fluoroscopy. Disadvantages are the additional cost represented by increasing pathology. Implants must be designed to give an answer on how the preoperative planning and simulation and by the creation of the PSI by rapid to provide reliable fixation in osteoporotic bone. Angle-stable plates and prototyping. Another disadvantage may be the need of a CT-scanner in a child nails, augmented implants and anatomically designed plates and nails with a (radioprotection). 3-dimensional locking pattern are some aspects that demonstrate that product innovations help surgeons in improving their radiological and clinical outcome. Orthopaedic trauma surgeons however should be aware that product innovations do require adapted surgical techniques. New implants used in a traditional manner do not necessarily lead to a better outcome. Surgeons and OR-personnel therefore must be familiar with the specific characteristics of the implants in order to avoid (predicable) failures.

102 Orthopaedica Belgica 2015 www.ob2015.org 103 I62 ADVANCED BEARINGS IN HIPS I63 IMPROVED OUTCOMES AND EFFICIENCIES USING POPULATION A. Kamali BASED DESIGN Smith &Nephew, Warwick, UK A. Petersik, G. von Oldenburg Stryker Trauma GmhH, Germany Many different materials have been used to replace the diseased hip joint in an attempt to alleviate pain and improve the mobility for hip arthritis patients. The An improved implant fit may foster safety and efficiency per and post implantation. materials may be selected depending on age, sex and activity level. The materials Reduced OR-time, increased contact of implant to bone, decrease in mal- used can be catagorized into four major groups; ceramics, metals, ceramicised alignment of fracture fragments and unnecessary soft tissue prominence may metal and polymers. A myriad of materials that have previously been used have be key enhancements. had varying levels of success. Each material used would have certain desirable characteristics; however all of them have had their limitations in vivo. In this talk, Traditionally, the design of implants for trauma and orthopedic surgery was based advanced bearings used in hip replacements will be reviewed in terms of their on limited datasets from cadaver trials or on artificial bone models. Recently, properties, advantages, limitations, clinical survivorship and potential reasons a method has been developed whereby implants shape can be optimized in cited for component failure. an evidence based method founded on a large anatomic database consisting of more than 13,000 datasets of bones extracted from CT scans. This method called SOMA (Stryker Orthopedic Modeling and Analytics) has been utilized to design anatomically shaped bone plates for fracture treatment (e.g. clavicle, pelvis, tibia) as well as for orthopedic applications like hip stems. On the one hand SOMA allows for automated anatomic measurements on all bones in the database providing design input. On the other hand, resulting designs may later be automatically fitted to each single bone in the database, allowing verification of the implants´ anatomic compliance.

Positive clinical feedback obtained on the shape of SOMA designed implants hints this method to be highly advantageous as compared to traditional design approaches.

Examples describing the SOMA capabilities and the typical approach of SOMA based shape optimization will be presented.

104 Orthopaedica Belgica 2015 www.ob2015.org 105 I64 THE DUTCH REGISTER All LROI data are published in the annual report (http://www.lroi.nl/nl/ J. Verhaar publicaties/jaarrapportage) and websites of the NOV informing patients Orthopaedics, Erasmus University Medical Center, Rotterdam, http://www.zorgvoorbeweging.nl and http://www.zorgvoorbeweging.nl/sites/ The Netherlands www.zorgvoorbeweging.nl/files/ZCard-LROI-LR10.pdf.

In 2007, the Dutch Arthroplasty Register (LROI) was initiated by the Netherlands To further improve quality of orthopaedic care the NOV has formulated Orthopaedic Association (NOV) to register patient and implant characteristics of criteria to sort implants in several categories based on their survival in public hip and knee prostheses in the Netherlands. The registration is financed by the registers and ODEP. Every year a new list is produced and published. The list for insurance companies but the register is owned by the LROI foundation which 2015 can be found on the NOV website. has a close relation with the NOV. The LROI is a member of the International http://www.orthopeden.org/vereniging/nieuws/nieuws/classificatie-totale-heup- Society of Arthroplasty Registries (ISAR) since 2010 and of the recently by Efort nov-advies-2015?objectSynopsis=clhw5DYtGNGBuxX9B83bdA#NOnC7aGNQ8 started Network of Orthopaedic Registers in Europe (NORE). 2u1oJ3zxjcMg;

The LROI registers variables, which describe the patient population, such as age, gender, and general health. In addition, patient case mix variables, such as body mass index (BMI), smoking behaviour, orthopaedic vitality (i.e. Charnley score) are included in the database. Adjusting for these case mix variables helps to improve comparability of care between hospitals. In 2013, the LROI completed a unique implant library for all registered hip and knee prostheses in the Netherlands. This implant library contains the name, type, and material of the prosthesis as well as coating, material of the liner, and the method of sterilisation. The LROI also offers the hospitals the possibility to collect patient reported outcome measures (PROMs). PROMs are measured with (digital) questionnaires to assess the effect of the prosthesis implantation on quality of life, pain, and level of functioning.

Since 2012 all hospitals in the Netherlands register in the LROI. For 2013, the completeness was 96% for primary total hip arthroplasties and primary knee arthroplasties. For hip revision arthroplasties, the completeness was 88%, for knee revision arthroplasties this was 90%. To further improve the completeness and validity the LROI visits the hospitals on a regular basis. Last year the LROI was extended with registration of ankle, shoulder and elbow arthroplasties. Also data of the national register of death were allowed to be used in the LROI, so the survival rate of prosthesis (the expected time to revision) can be determined correctly from now on. Many privacy issues had to be addressed before the LROI was allowed to include these data. Recently the Dutch Minister of Health, Welfare and Sports decided to set up a National Register for Implants. The main function of this register is traceability of all medical devices implanted in the Netherlands: tracing back an implant to a person. The LROI will be used as national source for the traceability of joint implants.

106 Orthopaedica Belgica 2015 www.ob2015.org 107 I65 IMPLANT REGISTRY IN BELGIUM: ORTHOPRIDE – WHERE ARE WE? T. Willems Dept. of Physiotherapy and Orthopedics, Ghent University, Belgium

In 2001, the Belgian Orthopedic Associations (BVOT and SORBCOT) recognized the need to establish a National Arthroplasty Registry. This was in part based on the documented success of a number of arthroplasty registries in other countries and the publication of a report made by a private health insurer about hip replacement. However, it took several years before the National Arthroplasty Registry was established. In September 2008, the National Institute for Health and Disability Insurance together with the Orthopedic Associations agreed to fund the Registry development. Data collection on hip and knee replacement surgery in our National Arthroplasty Registry, called Orthopride started in September 2009 on a voluntary basis. Since 2013, the National Institute for Health and Disability Insurance and the Flemish Orthopedic Society provide funding to maintain the Registry.

Data collection in 2009 and 2010 was scarce (<7% of performed knee and hip replacements in Belgium), but started to grow from 13% in 2011, over 19% in 2012, 23% in 2013 to 50% in 2014. In July 2014, registration of knee and hip replacements became mandatory, but verification is not performed. However, from September 2015, hip and knee implant reimbursement will be coupled with the registration in Orthopride. It is anticipated that in the upcoming years the Registry will contain almost 100% of hip and knee replacements performed in Belgium.

The purpose of Orthopride is to define, improve and maintain the quality of care for patients receiving joint replacement surgery. This is achieved by collecting a defined minimum data set that enables outcomes to be determined based on patient characteristics, prosthesis type and features, method of prosthesis fixation and surgical technique used. These collected data are used to investigate the quality of knee and hip replacement surgery and the lifespan of the prosthesis. Since the origin of Orthopride, several limitations in the data collection and Abstracts of validation were noticed. Many were adapted in a new and more appropriate version which was released in January 2015. Since then, some additional patient the Residents Session characteristics as alignment and previous operations are collected. Before 2015, prostheses identification data were collected by means of free text fields, but are now gathered by notification codes, a unique Belgian code. Later this year, orthopedic surgeons will be able to draw their own statistics and to compare those to national data.

One of the key moments was the obligation of registration in 2014, which was necessary to increase the scientific value of the National Registry which will ultimately lead to an increase in quality of care for the patient.

108 Orthopaedica Belgica 2015 O1 COMPARISON OF INTERVERTEBRAL DISTANCES BASED ON O2 IMPACT OF CEMENT MANTLE THICKNESS ON LOCAL AND VERTEBRAL VECTORS IN NORMAL SUBJECTS AND IN IDIOPATHIC SYSTEMIC GENTAMICIN CONCENTRATIONS IN TOTAL HIP SCOLIOSIS: IS IT AN EFFECT OF THE SPINAL CORD PROTECTION? ARTHROPLASTY H. Bhogal1, B. Király2, S. Somoskeőy3, F. Lauer4, T.S. Illés1,5 W. Van IJperen, T. Scheerlinck 1Dept. of Orthopedics & Traumatology, Brugmann University Dept. of Orthopaedics and Traumatology, UZ Brussel, Brussels, Hospital, ULB, Brussels Belgium; 2Dept. of Applied Mathematics, Belgium 3 Institute of Mathematics and Informatics and Orthopedic Depts., 4 Pécs University, Hungary; LORIA, Lorraine Research Laboratory Aim in Computer Science and its Applications, University of Lorraine, We investigated the relationship between cement mantle thickness and Nancy, France; 5Dept. of Orthopedic Surgery, Odense University Hospital Svenborg, Sygehus, University of Southern Denmark, gentamicin concentrations in serum and drain fluid after hybrid hip arthroplasties Odense, Denmark fixed with gentamicin loaded cement.

Introduction Materials and Methods Determination of the intervertebral rotational axis on thoracic and lumbar area of We compared in a randomized, non-blinded and prospective study, the local and the healthy spine is contradictory, as well is the determination of this axis during systemic gentamicin concentrations in two patient groups. Group A received a the development of idiopathic scoliosis. Our goal is to determine the location of stem implanted line-to-line with the broach (Vectra®, Biomet, thin cement mantle, intervertebral rotation axes for normal and scoliosis spine using mathematical 16 patients), whereas in group B an undersized stem was used (CPT®, Zimmer, analysis based on the vertebra vector visualization. thick cement mantle, 14 patients). All stems were cemented with hi-fatigue Materials and Method gentamicin bone cement (AAP). Gentamicin concentrations were measured 137 healthy and 814 cases of idiopathic scoliosis patients underwent in in drain fluid and serum at set intervals for three days postoperatively and standing position simultaneous AP and lateral X-rays using the EOS™ 2D/3D compared with a t-test. system. Whole spine surface 3D reconstructions of all patients were carried out by sterEOS 3D software based on EOS™ X-ray images. A vertebra vector Results is a simplified representation of the real vertebra of the spine, and is based on Despite differences in implantation technique, the amount of cement used in known vertebral landmarks. Following the creation of the vertebra vectors of both groups was similar (A: 33.1 g (SD 51.4); B: 37.5 g (SD 51.5), p=0.118). In both the spine, vectors were placed in a coordinate system in order to determine groups, local gentamicin concentrations were similar and declined rapidly: 4-8 the x, y, and z coordinates of their initial and terminal points. This coordinate hours postoperatively A: 54.61 mg/L (SD 1246.53), B: 57.66 mg/L (SD 326.91), system was created using principles described by SRS Working Group on the 3D p=0.771; 20-28 hours A: 18.25 mg/L (SD 175.21), B: 17.28 mg/L (SD 119.59), p=0.829. Terminology of Spinal Deformity. Thus obtained large database was analyzed After 44-52 hours local gentamicin decreased below the Minimal Inhibitory mathematically using Multi-Class Support Vector Machine (M¬–SVMs) software. Concentration (MIC) of 5 mg/L in 10/13 cases in group A and 15/16 in group B. In Results both groups, the serum gentamicin concentration never exceeded toxic levels of The results M¬–SVMs analysis on healthy spines shows that the intervertebral 2 mg/L (maximum 1.08 mg/L). distance on the level of initial points of vertebra vectors is individually determined and always constant. The intervertebral distances do not depend on the size of Discussion the vertebrae. We also observed the same characteristics in all cases of scoliosis Cement mantle thickness around the stem did not influence local gentamicin spine. concentrations in hybrid hip arthroplasty. In all cases, the MIC was exceeded in the initial 4-8 hours, making addition of local antibiotics unnecessary even for Discussion thin cement mantles. No systemic toxic serum levels were reached during the Our finding indicates that the lengths of spinal cord between each vertebral segment are constant, because the initial points of vertebra vectors situate inside study. the spinal canal. The same observation is true for all scoliosis spines also. These observations biomechanically may be true, only if the rotational axis of spine and the starting points of vertebra vectors coincide. This coincidence is necessary to protect the spinal cord against the cigar cutting effect during the excessive vertebral rotation, namely during the development of scoliosis deformity. 110 Orthopaedica Belgica 2015 www.ob2015.org 111 O3 DESCRIPTION OF THE VERTEBRAL SPINE CURVATURES Discussion RELATIONS USING THE TOP VIEW APPROACH The Top View provides a quick and precise diagram presenting 3 dimensions, S. Martinov, T. Illés allowing the surgeon to use it in pre-operative planning, as an intra-operative Brugmann University Hospital, Orthopedics and Traumatology Dept., reference and for post-operative control. The spine image can be quickly obtained Brussels, Belgium and it generously represents all the needed values on a convenient chart. Going beyond purely sagittal balance, this approach permits the visualization of the Introduction most challenging kypho-scoliotic deformities. Furthermore, it might have the Scoliosis is a multifactorial three-dimensional spinal deformity with integral potential to generate a desired, balanced spine of a patient based on scrupulous and directly related vertebral deviations in the coronal, sagittal and horizontal calculations, which was previously attempted to be achieved only intuitively. planes. Current classification and diagnostic methods rely on two-dimensional frontal and lateral X-ray images. So far, there was no tool to display all three planes appearance of spinal deformities in a single image. This study is aiming to describe the normal sagittal curvatures, using only the horizontal plane view, depicting all 3 dimensions at same time.

Methods This work includes the analysis of 138 spines without scoliosis. All vertebral columns were visualized using the EOS system, a low radiation dose device, which allows high-quality, realistic 3D visualization. The vertebra vectors are simplified representations of the vertebrae of the spine, and based on known vertebral landmarks. Following the creation of the vertebra vectors of the spine, vectors were placed in a coordinate system in order to determine the x, y, and z coordinates of their initial and terminal points. Using the Top View images all the vertebra vector of thoracic kyphosis and lumbar lordosis were described in their sagittal plane, still visualizing the coronal and horizontal ones.

Results Calibration scale of the coordinate system is based on the interacetabular distance in horizontal plane view. A value of 100X2 is assigned to the distance between the acetabular centers. The line from acetabular centroid can be drawn to any of the vertebra vectors. In this instance we chose L1 vertebra. In the right angle triangle the A’ angle can be calculated. Since all the vertebra vectors are aligned along the Y-axis, the adjacent side of the triangle is always 100, the opposite side of A’ is given and is 67. Dividing the adjacent by opposite sides and obtaining the tangent-1 of 0.67 we receive the angle A’ of 33,8°. All the rest of the vertebrae are calculated in the same manner. The precise angulation of the entire vertebral column is constructed. 112 Orthopaedica Belgica 2015 www.ob2015.org 113 O4 RELIABILITY OF PATIENT-SPECIFIC GUIDES IN TOTAL KNEE ARTHROPLASTY M.A. Ngo Yamben, H. Jennart, D. Zorman Dept. of Orthopaedic and Traumatology , CHU Tivoli, La Louvière, Belgium

The main challenge of total knee arthroplasty is to restore a correct mechanical axis of the leg with an accurate positionning of the implants for ligament balancing. The common technique refers to intra and extramedullary ancillary and achieves to restore the mechanical axis in 90-92%. Navigation increases these results to 98%. The new method based on the pre-operative manufacture of personalized guides of TKA seems to be easier, and maybe more accurate and reproducible.

The aim of our study is to evaluate the accuracy of this recent alternative and compare it to the results of a large literature review.

We prospectively recruited 80 patients. The study was performed in a single center by two senior surgeons. The first group (n=40) was operated with navigation and the second group (n=40) with the patient-specific guides controlled by navigation. Long-leg and standard radiography were always done prior to surgery for mechanical axis measurements and component sizing in the first group. An MRI was added to manufacture the anatomical prosthetic guides in the second group. The varus or valgus tibial and femoral angles, the tibial tilt and the osseous tibial and femoral resection heights were measured before and after surgery for each patient. The differences between the pre-operative planification and post-operative results were also evaluated. We established our own objective score to compare the accuracy of the implant positioning in these two groups. We will discuss our results including the literature.

Exhibitors

114 Orthopaedica Belgica 2015 Exhibitors 3D-Side Arthrex BelgaFix Biomet Belgium Biotech Benelux Bone Therapeutics S.A. Cyberdyne Care Robotics GmbH De Soutter Medical Belgium Major Sponsor DNAlytics eXmedical H. Nootens Heraeus Medical Belgium Hospital Innovations - Ortho Medico Johnson & Johnson Medical - DePuy Synthes Johnson & Johnson Medical Belgium K2S Mathys Orthopaedics Belux MBA Belgium & Luxembourg Mobelife Onbone Oy Smith & Nephew Sprofit Stanmore Implants Stöpler Belgium Stryker TRB Chemedica Zimmer

116 Orthopaedica Belgica 2015 www.ob2015.org 117 General Information

118 Orthopaedica Belgica 2015 Registration Social Programme

Registration Fees Gala Dinner on Thursday, 23 April 2015 As of The Orthopaedica Belgica 2015 Gala Dinner will take place at the ‘Château de 16/03/2015 la Hulpe’ also known as the ‘Solvay Castle’. The castle was built in French style One Day Registration by the Marquis de Béthune in 1842. Both the castle and estate were acquired Senior Member BVOT/SORBCOT (Wednesday) € 140,00 by Ernest Solvay in 1893, to make it his summer residence, hence its popular denomination. Count Solvay trusted Victor Horta with the interior decoration. Non-Member MD (Wednesday) € 175,00 Today the estate is owned by the regional government of , and is Senior Member BVOT/SORBCOT € 275,00 classified as an ‘Exceptional Heritage Site in Wallonia’. (Thursday or Friday) Non-Member MD (Thursday or Friday) € 350,00 While the grounds are open to the public, the castle itself cannot be visited, unless…. you join us for the Gala Dinner and access the ground floor of the Trainee Member BVOT/SORBCOT* € 150,00 Château, with its superb reception rooms – some more intimate like the Chinese Trainee Non-Member* € 175,00 Room, some more stately like the Great Hall – together they make up a tranquil Non-MD (Physiotherapist, Engineer, ... ) € 100,00 and harmonious ensemble. Full Congress Registration Château de la Hulpe – Kasteel van Terhulpen Senior Member BVOT/SORBCOT € 450,00 Chaussée de Bruxelles, 111 B- 1310 La Hulpe Non-Member MD € 600,00 www.chateaudelahulpe.be Trainee Member BVOT/SORBCOT* € 150,00 Separate registration is required. Rate per person: 90,00 € (as of 16/03). Trainee Non-Member* € 200,00 The number of seats is limited. Non-MD (Kiné, Ergo, Ingénieur, ... ) € 150,00

Nursing Congress (Friday, April 24) € 100,00 Gala Dinner (Thursday, April 23)** € 90,00 *Registration as a trainee will only be accepted if accompanied by a certificate of the training director. **Limited number of seats available.

Cancellation Participants cancelling before March 15 will receive a 50% refund. There will be no refunds for cancellations received after this date. A written cancellation is mandatory for receiving a refund. All refunds will be made after the Congress.

Farewell Belgian Beer Reception on Friday, 24 April 2015

The Farewell Belgian Beer Reception will take place in the foyer of the Aula Magna and is offered to all participants and exhibitors.

Pre-registration is requested.

120 Orthopaedica Belgica 2015 www.ob2015.org 121 General Information General Information

Venue Accreditation and Certificate

Aula Magna A request for accreditation (also for Ethics and Economy) has been submitted to B-1348 Louvain-la-Neuve the RIZIV / INAMI. Participants will receive a Certificate of Attendance by email at www.aulamagna.be the end of the Congress. GPS: Boulevard André Oleffe Language

The official language is English. There is no simultaneous translation.

How to get there? Exhibition

GPS address to enter the city: Boulevard André Oleffe In conjunction with the Congress, a technical exhibition highlighting technical Then follow UCL signs ‘Orthopaedica Belgica’ to Parking Grand-Place. equipment and pharmaceutical products will be held in the exhibition area of The Parking Grand-Place is located in front of the Aula Magna. the Congress Centre. Access to the exhibition is free for all participants. The exhibition is not accessible for non-MDs. Where to park? Liability The Parking Grand-Place is located in front of the Aula Magna. Neither the organisers, nor the local committee accept liability for damages and/ or losses of any kind which be incurred by participants during the Congress. Participants are advised to take out insurance against loss, accidents or damage which could be incurred during the Congress.

Organisation

Medicongress Noorwegenstraat 49 9940 Evergem Phone: + 32 (0)9 218 85 85 Fax: + 32 (0)9 344 40 10 Email: [email protected]

Public Transport By train: Station Louvain-la-Neuve. The Aula Magna is located at walking distance from the train station.

122 Orthopaedica Belgica 2015 www.ob2015.org 123 OSTENIL® Line Decrease Joint Pain Improve Joint Function Treatment of Osteoarthritis

Manufacturer: TRB CHEMEDICA AG · Postbox 1129 · 85529 Haar/München, Germany [email protected] · www.trbchemedica.be

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