THE EFFECT OF THE TRIPLE TIBIAL OSTEOTOMY PROCEDURE ON CRANIAL TIBIAL SUBLUXATION AND INTERNAL TIBIAL ROTATION: A RADIOGRAPHIC CADAVER STUDY Angus McMillan Bachelor of Veterinary Science A thesis submitted to Charles Sturt University of the Degree of Master of Veterinary Studies School of Animal and Veterinary Science Charles Sturt University NSW, Australia March 2020 1 Table of Contents Certificate of Authorship ......................................................................................................4 Acknowledgements ..............................................................................................................5 Abstract ................................................................................................................................6 List of Figures .......................................................................................................................7 List of Tables .........................................................................................................................9 List of Abbreviations ............................................................................................................9 1. Introduction ....................................................................................................................10 2. Literature Review ..........................................................................................................13 2.1 Introduction to Cruciate Disease .............................................................................13 2.2 Anatomy of the Canine Stifle ...................................................................................14 2.3 Epidemiology of Cruciate Disease ............................................................................17 2.4 Non-surgical Management of CCL Rupture ..............................................................20 2.5 Surgical Management of CCL Rupture ......................................................................21 2.6 Outcomes and Comparisons of TPLO, TTA and LFTS ................................................26 2.7 Popularity of Tibial Osteotomy Procedures .............................................................27 2.8 Concurrent Meniscal Injury ......................................................................................27 2.9 Use of Loading Studies to Evaluate Proximal Tibial Osteotomy Techniques ...........28 2.10 Triple Tibial Osteotomy ..........................................................................................30 2.11 Conclusions .............................................................................................................34 2.12 Study Objectives .....................................................................................................35 3. Materials and Methods ..................................................................................................36 3.1 Study Design .............................................................................................................36 3.2 Limb Harvesting ........................................................................................................36 3.3 Loading Frame ..........................................................................................................37 3.4 Limb Preparation ......................................................................................................38 3.5 Limb Testing ..............................................................................................................41 3.6 Triple Tibial Osteotomy Procedure ...........................................................................43 3.7 Statistics Recording ..................................................................................................45 3.8 Statistics ....................................................................................................................45 4. Results ............................................................................................................................46 4.1 Sample and Limb Exclusions .....................................................................................46 4.2 Pre-operative Investigation ......................................................................................48 4.3 Effect of Transection of the Cranial Cruciate Ligament (CCL) ..................................48 2 4.4 Effect of the Triple Tibial Osteotomy Procedure (TTO) ............................................48 4.5 Wedge Accuracy .......................................................................................................51 4.6 Intraoperative Complications ...................................................................................51 5. Discussion .......................................................................................................................54 5.1 Sample Population and Exclusions ...........................................................................54 5.3 Effect of CCL Transection ..........................................................................................57 5.4 Effect of the TTO on the CCL deficient stifle ............................................................58 5.5 Wedge Osteotomy Assessment ................................................................................61 5.6 Persistence of CTS after Proximal Tibial Osteotomies .............................................61 5.7 Intraoperative Complications ...................................................................................64 5.8 Limitation and Future Directions ..............................................................................65 5.9 Conclusions ...............................................................................................................68 6. General Discussion .........................................................................................................69 6.1 Radiographic Cadaver Studies ..................................................................................70 6.2 The TTO as a Proximal Tibial Osteotomy ..................................................................71 6.3 Conclusions ...............................................................................................................72 6. References ......................................................................................................................73 3 Certificate of Authorship I hereby declare that this submission is my own work and that, to the best of my knowledge and belief, it contains no material previously published or written by another person nor material which to a substantial extent has been accepted for the award of any other degree or diploma at Charles Sturt University or any other educational institution, except where due acknowledgment is made in the thesis. Any contribution made to the research by colleagues with whom I have worked at Charles Sturt University or elsewhere during my candidature is fully acknowledged. I agree that this thesis be accessible for the purpose of study and research in accordance with the normal conditions established by the Executive Director, Division of Library Services or nominee, for the care, loan and reproduction of theses. Date: Angus McMillan BVSc 4 Acknowledgements I would like to acknowledge and thank the following people for their support and involvement during the course of my Masters candidature. Most of all I am grateful for Dr. Randi Rotne, Dr. Kieri Jermyn and Dr. Tania Banks for their encouragement, guidance and time in all aspects of the project from initial design through to the limb testing, assistance with statistics and multiple revision of drafts. Assoc. Prof. Kristopher Hughes my principal supervisor who helped navigate much of the bureaucracy of University research and for generally providing guidance and review throughout the project. Frances Paterson at the VCC who in addition to assistance with imaging was present for almost all the limb testing which was a morbid and thankless task. The staff at the SARH who always went above and beyond to help in whatever way was required – Nat McCraig, Leanne Barnett, Stephanie Browning, Jess Griffith and Kate Whalan especially. Thanks to Felicity Stanley and Tim Headon at the anatomy labs for their assistance with limb harvesting and storage. Dr. Jane Lord, Dr. Ali Montgomery and Dr. Martin Combs for their collegial support and friendship during my time at CSU. Finally my parents, Ian and Kate. Both endlessly supportive of anything I’ve ever done. 5 Abstract Cranial cruciate ligament (CCL) rupture is a common cause of pelvic limb lameness in the dog. There are a multitude of techniques to address the instability associated with CCL rupture however recently the proximal tibial osteotomy techniques whereby the anatomy of the proximal tibia is changed to create an environment where an intact CCL is not required for stability have become generally favoured by specialist surgeons and the scientific literature. The Triple Tibial Osteotomy (TTO) is one such of these techniques however relative to its contemporaries, the Tibial Plateau Levelling Osteotomy and the Tibial Tuberosity Advancement, there is scant literature published on the technique. A radiographic cadaver study was performed to assess the effect of the TTO procedure on the cranial tibial subluxation (CTS) and internal tibial rotation (ITR) that occurs in a cranial cruciate ligament deficient stifle. The study confirmed and quantified