RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES BANGALORE, KARNATAKA. ANNEXURE –II PROFORMA FOR REGISTRATION OF SUBJECT FOR DISSERTATION

1 Name of the candidate . DR.SHREEKANTHA.K.S

Address NO.105,GAYATRI NILAYA, 12TH B MAIN, 6TH BLOCK, RAJAJINAGAR, BANGALORE-560010. 2 Name of the institution BANGALORE MEDICAL COLLEGE AND . RESEARCH INSTITUTE, BANGALORE. 3 Course of Study and M.S. ORTHOPAEDICS . Subject 4 Date of 19\O6\2013 . Admission 5 Title of the topic EVALUATION OF SOFT TISSUE BALANCING . AT MIDFLEXION IN TOTAL KNEE ARTHROPLASTY. 6. Brief resume of intended work

6.1. Need for study:

Total knee arthroplasty (TKA) is one of the most common surgical procedures in orthopaedics. It is the treatment of choice for advanced arthritis of the knee. The aim of TKA is to achieve long-term implant survival and successful functional outcome with minimal complications and cost effectiveness. [1]

Symmetric ligament balance is considered a prerequisite for good function and endurance in total knee arthroplasty. This is achieved via the removal of any osteophytes that may hinder articulation, as well as the lengthening and dissecting of tight ligamenture.[2] In the current surgical practice, the soft tissue balancing is done in full extension and 90° flexion and after bone preparation is completed, the flexion and extension gaps should be evaluated for symmetry for equal height in flexion and extension.[1]

Mid-flexion instability is an issue that has only recently gained the attention of knee arthroplasty surgeons.[3] Most of everyday activities like sitting on a chair, getting up from sitting, claimbing up and down the stairs, etc requires midflexion stability of knees. The goal of our study is to evaluate soft tissue balancing at Midflexion and assess variability compared to balancing at 90° flexion and extension.

6.2 Review of literature:

Campbells operative orthopaedics, 12th Edition states that the flexion and extension gaps should be evaluated for symmetry for equal height in flexion and extension and soft tissue balancing can be done with laminar spreaders, spacer blocks, or computer navigation techniques.[1]

Scott And Insall Surgery of Knee 5th Edition states that the most important factor for maintaining satisfactory long-term outcome in TKA is anatomic alignment, which depends significantly on ligamentous balance and accurate bone resection. Although bone cuts can be made to establish anatomic alignment, proper ligamentous balance is required to maintain alignment throughout the range of motion and laminar spreaders are useful in monitoring soft tissue balance and the performance of ligament releases.[2] Mid Flexion Instability After Primary Total Knee Arthroplasty, a study conducted by Rajeev Kumar Sharma concludes that mid flexion instability is a newer concept, the causes of which and further management protocols needs to be worked out.[3] Intra-Operative Assessment of Mid-Flexion Instability in Total Knee Arthropalsty , a study conducted by Yukihide Minoda et al concluded that the joint gap after implantation was tight in extension and deep flexion and became loose in mid-flexion. This mid-flexion instability was shown during the position in which post and cam did not engage and might result in paradoxical forward translation of femoral component in mid-flexion range.[4]

Dynamic intraoperative ligament balancing for total knee arthroplasty, a study by D'Lima DD, et al concluded that although reasonable balance was achieved at 0-degree and 90-degree flexion, there was some measurable imbalance at flexion angles other than 0 degrees and 90 degrees.[5]

A new method to measure ligament balancing in total knee arthroplasty: laxity measurements in 100 knees, a study by Eirik Aunan et al used a set of four polyethylene spatulas with thicknesses from 2 to 5 mm to measure the medial and lateral gaps and concluded that method for measuring ligament balance is reliable and provides valuable information in assessing laxity intra-operatively.[6]

Causes of Instability After Total Knee Arthroplasty, a study by Sang Jun Song,et al identified six categories: flexion/extension gap mismatch, component malposition, isolated ligament insufficiency, extensor mechanism insufficiency, component loosening, and global instability. Twenty-five knees presented with multi-factorial instability. When these knees were classified according to the most fundamental category, each category above included 24, 12, 11, 10, 10 and 16 knees respectively. The unstable TKA may result from a variety of distinct etiologies which must be identified and treated at the time of revision.[7]

The Failed Total Knee Arthroplasty: Evaluation and Etiology, a study by Mark H. Gonzalez,et al concluded instability after total knee arthroplasty results from improper balancing, inappropriate component size, and component failure. Posterior instability generally occurs during flexion. Medial-lateral instability can result from either improper balancing of components or incompetent collateral ligaments.[8]

Mid-flexion laxity is greater after posterior-stabilised total knee replacement than with cruciate-retaining procedures: A computer navigation study, a study by Hino K et al concluded posterior-stabilised knees had more varus-valgus laxity than cruciate-retaining knees at all angles examined, and the differences were statistically significant [9]

The influence of total knee arthroplasty geometry on mid-flexion stability: An experimental and finite element study ,a study by Chadd W. Clary, et al concluded

incorporating a gradually reducing radius in mid-flexion reduced the magnitude of paradoxical anterior translation between 21% and 68%, depending on the conformity of the tibial insert.[10]

Coronal Stability Of The Knee After Total Knee Arthroplasty with Gap Balancing Technique, a study by H. Fujii, et al concluded gap balancing may contribute to improved functional performance after TKA by providing better coronal stability of the knee in the 90 degree flexed position.[11]

Instability Following Total Knee Arthroplasty, a study by E. Carlos Rodriguez- Merchan,et al concluded successful outcomes in revision TKA can be obtained in many of these cases, but without identifying the cause of instability, the surgeon risks repeating the mistakes that led to the instability after the initial TKA. [12]

6.3. Aims and Objectives of the study:

1) To evaluate soft tissue balance at Midflexion in addition to routine balancing of knee at extension and 90° flexion before and after placing Final Prosthetic Components in Total Knee Arthroplasty.

2) To assess and look for reasons of variability of soft tissue balance at Midflexion compared to balancing at full extension and 90° flexion.

7. Materials and Methods

7.1. Source of Data

Adult patients of either sex undergoing Total Knee Arthroplasty in Victoria Hospital and Bowring & Lady Curzon hospital attached to Bangalore Medical College & Research institute.

7.2. Method of collection of data:

A. Study design: A prospective study.

B. Study period: Oct 2013 to May 2015.

C. Place of study: Victoria hospital and Bowring & Lady Curzon hospitals.

D. Sample size: It is a hospital based study of minimum 20 cases who are fulfilling the Inclusion/Exclusion criteria.

E. Inclusion criteria: 1. Patients who are undergoing Primary Total Knee Arthroplasty for Osteoarthritis Knee and Rheumatoid Arthritis of Knee. 2. Patients who have given Informed Written Consent for the proposed procedure.

F. Exclusion criteria: 1. Patients not willing to be part of the study. 2. Patients with traumatic arthritis of knee. 3. Patients with extensor mechanism dysfunction. 4. Patients with vascular disease of lower limbs. 5. Patients with recurvatum deformity of knee. 6. Patients with remote source of infection. 7. Patients with medical contraindications for surgery.

G. Methodology:

Inpatients of Victoria hospital and Bowring & Lady Curzon hospital undergoing Total Knee Arthroplasty fulfilling the inclusion & exclusion criteria will be taken in to study after obtaining informed written consent. Demographic data, History, Clinical examination and details of investigations will be recorded in the study proforma. Routine surgical procedure of Posterior Stabilised Primary Total Knee Arthroplasty is followed with Soft tissue balancing at 90° flexion and extension and Midflexion instability evaluated with Laminar Spreader and Polyethylene Spatulas for mediolateral instability and Anterior tibial translation for anteroposterior instability with Trial components in situ.

Follow Up: After 15 days, 1 month, 3 months, 6 months, 1 year after Surgery.

H. Statistical method: Suitable statistical test is used.

7.3. Does the study require any investigations or interventions to be conducted on patients or other humans or animals? If so, please describe briefly 1. Investigations required are: Routine Investigations like CBC, RFT, LFT, Coagulation Profile, Urine Routine, Chest X-Ray, ECG. 2. Special Investigation: X-ray Both Knees AP/Lat/Skyline views, Xray Scannogram of Both Lower Limbs. 3. No animal study is required.

7.4. Has the ethical clearance been obtained from your institution in the case of 7.3? Yes.

8 References :

1. S.Terry Canales, Campbells Operative Orthopaedics, 12thedition, Pages 376-444, Mosby Publishers. 2. Insall & Scott Surgery of the Knee, 5th Edition,Pages 896-1410,Elsevier Publications.

3. Rajeev Kumar Sharma, Mid Flexion Instability After Primary Total Knee Arthroplasty, Bone and Joint Journal 2013 vol 95-B no.SUPP 15 326. 4. Yukihide Minoda, Shigeru Nakagawa, Akio Kobayashi,et al, Intra-Operative Assessment of Mid-Flexion Instability in Total Knee Arthropalsty, American Academy of Orthopaedic Surgeons, Annual Meeting Thursday, Mar 21, 2013.

5. D'Lima DD, Patil S, Steklov N, Colwell CW Jr., Dynamic intraoperative ligament balancing for total knee arthroplasty, Clinical Orthopaedic Related Research. 2007 Oct;463:208-12.

6. Eirik Aunan, Thomas Kibsgard, John Clarke-Jenssen, et al, A new method to measure ligament balancing in total knee arthroplasty: laxity measurements in 100 knees, Arch Orthop Trauma Surg (2012) 132:1173–1181.

7. Sang Jun Song, Robert C. Detch, William J. Maloney et al , Causes of Instability After Total Knee Arthroplasty, The Journal of Arthroplasty,Available online 26 July 2013.

8. Mark H. Gonzalez, Anis O. Mekhail, et al, The Failed Total Knee Arthroplasty: Evaluation and Etiology, Journal Of American Academy Orthopaedic Surgeons, November/December 2004vol. 12 no. 6 436-446. 9. Hino K, Ishimaru M, Iseki Y, et al Mid-flexion laxity is greater after posterior- stabilised total knee replacement than with cruciate-retaining procedures: A computer navigation study, Bone Joint Journal 2013 Apr;95-B(4):493-7.

10. Chadd W. Clary, Clare K. Fitzpatrick, Lorin P. Maletsky,et al The influence of total knee arthroplasty geometry on mid-flexion stability: An experimental and finite element study, Journal Of Biomechanics, Volume 46, Issue 7, Pages 1351-1357, 26 April 2013. 11. H. Fujii, Y. Azumaand,K. Doi,et al Coronal Stability Of The Knee After Total Knee Arthroplasty with Gap Balancing Technique, Journal of Bone And Joint Surgery 2012 Vol 94-B no. SUPP XLI 5.

12. E. Carlos Rodriguez-Merchan,et al Instability Following Total Knee Arthroplasty, HSS Journal 2011 October; 7(3):273-278.

9. Signature of the candidate:

10. Remarks of the Guide: As there are few literature about Midflexion Instability and the causes for Midflexion instability are still uncertain. Hence this study has been chosen.

11. Name and Designation Dr. P K RAJU 11.1.Guide: MBBS, MS (ortho); D ortho, Associate Professor and Unit Chief, Dept. of Orthopedics, Bangalore Medical College and Research Institute, Bangalore. 560002

11.2. Signature:

11.3 Co-guide (if any):

11.4. Signature:

11.5.Head of the Department: Dr. MANJUNATH. K .S D ortho, DNB (ortho) Professor and Head of the Department. Dept. of Orthopaedics Bangalore Medical College & Research Institute, Bangalore. 560002

11.6. Signature: 12 12.1.Remarks of the Chairman and Principal:

12.2 Signature:

ANNEXURE I

I, Mr/Mrs/Ms______, exercising my own free will power of choice, hereby give consent for myself as an object in EVALUATION OF SOFT TISSUE BALANCING AT MIDFLEXION IN TOTAL KNEE ARTHROPLASTY, the study conducted by Dr. SHREEKANTHA K S, post graduate in orthopaedics under the guidance of Dr. P K RAJU, Associate Professor, Department of orthopaedics, Bangalore Medical College and Research Institute.

The attending doctors have informed me to my satisfaction and in the language best understood by me, the purpose of this study, the materials to be used during the course of this study as well as the side effects / complications associated with the methods/tools to be used. I shall not hold the doctors or the staff responsible for any untoward consequences. I am also aware of my right to opt out of the study without prejudice to further treatment at any time during the course of the study without having to give any reasons to do so.

Signature of the attending doctor: DATE:

Signature of the witness: Signature/Left thumb DATE: impression of the patient