SA Orthopaedic Journal
versión On-line ISSN 2309-8309
BACKGROUND: Very few direct comparative studies evaluating the results after unicompartmental knee replacement (UKA) and total knee replacement (TKA) are available. Only three previous studies have reported the results of UKA and TKA performed in the same patient. We report our results of simultaneous UKA and TKA in the same patient, performed under the same anaesthetic, at same the time, by the same surgeon. This is the first study to assess the results of UKA and TKA in the same patient, where all the patients had the procedures performed under the same anaesthetic at the same time MATERIALS AND METHODS: Twenty-one patients who had simultaneous primary UKA in one knee and primary TKA in the other knee were evaluated prospectively by means of the SANE (Single Assessment Numerical Evaluation) rating. In addition each patient was asked the simple question: "Which is your preferred knee?" RESULTS: The follow-up period was a mean of 26 months (range 12-58 months). We found a statistically significant improvement in the SANE in both the UKAs and TKAs. Eleven patients had no preference between the UKA and the TKA (52.4%), seven patients preferred the TKA (33.3%) while three patients stated that the UKA was their preferred knee (14.3%). The trend for patients to prefer the TKA was not statistically significant (p= 0.27). CONCLUSIONS: UKAs have been shown to be kinematically superior and the preservation of the cruciate ligaments affords better proprioception than a TKA. However, the findings of this study suggest that this does not translate to a better patient preference. In view of this finding, and considering the documented inferior survival rates of UKAs, we propose that the role of UKA in the treatment of gonarthrosis be reassessed.