Abstract
Introduction and Aims: The purpose of the study was to determine whether the addition of screws improved the fixation of the tibial base plate when using an uncemented total knee replacement.
Method: In June 1999 a prospective randomised double blind study on tibial base plate fixation was started at our institution after Ethics Committee approval. Patients were randomly allocated to either having or not having supplementary screws inserted through the base plate. To date, 138 arthroplasties have been performed and 119 are available for study. Of these, 56 have screws through the base plate and 63 do not. Assessment was of the position of the components of the prostheses, as well as the presence of any radiological lucent lines.
Results: The study is ongoing, and updated results will be presented. After a minimum of 12 months follow-up, 27 patients have some radiolucent lines at the prosthesis-bone interface on the tibial component of the knee replacement. Fourteen occurred where screws had been used and 13 when screws had not. One tibial tray subsided into the tibia without failure of fixation. No screws had been used in this case. Statistically no difference could be demonstrated between the two groups.
Conclusion: The early results of our study question the value of supplementing base plate fixation in uncemented total knee replacements, especially considering the additional cost of the screws and the potential detrimental consequences of the screws.
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.
At least one of the authors is receiving or has received material benefits or support from a commercial source.
