Abstract
Introduction and Aim: Following the establishment of the Australian Orthopaedic Association National Joint Replacement Registry, the Australian orthopaedic community has quality prosthesis specific information on knee replacement. This presentation details the demographics of primary total knee replacement, types of prostheses used, methods of fixation and the incidence of, and reasons for, early revision.
Results: Over 36,000 primary total knee replacements with almost 400 subsequent revisions were recorded. Primary total knee replacements were undertaken more commonly in females (56.4%), mostly for osteoarthritis (95.9%), with a mean subject age of 69.6 years.
The Registry recorded 56 different knee prostheses with the 10 most common accounting for 85.5% of all procedures. The patella was not replaced in the majority of cases (58.5%), however this varied considerably with prosthesis type and method of fixation. Cement fixation of the tibial component occurred in 76.9% of cases and the femoral component in 49.5%. Most commonly the insert was fixed (71.3%) and minimally stabilised (86.7%). Posterior stabilised inserts were used in 12.8% of primary cases. The cumulative revision rate at one year was 1.0% and 2.1% at two years. Early revision was minor in 54.1% of cases and major in the remainder. The most common reasons for minor revision were patello-femoral pain (27.1%) and infection (21.7%); for major revision, early loosening (40.2%) and infection (27.5%). Prosthesis type, patella use, method of fixation, degree of constraint and the use of fixed, rotating and/or sliding inserts did not significantly affect revision rates at this early stage.
Conclusion: Although variation is seen in early revision rates depending on the prosthesis type, patella use, method of fixation and other prosthesis specific characteristics, these differences are currently not significant.
These abstracts were prepared by Editorial Secretary, George Sikorski. Correspondence should be addressed to Australian Orthopaedic Association, Ground Floor, The William Bland Centre, 229 Macquarie Street, Sydney, NSW 2000, Australia.
One or more of the listed authors are receiving or have received benefits or support from a recognised academic body for the pursuance of the study.
