Abstract
Aim
We aim to compare revision rates and functional outcome scores in between two contemporary total knee arthoplasty systems.
Methods
A search was carried out of a prospectively maintained outcomes database to identify all patients receiving total knee replacement (TKR) in the department between 2005 and 2006, when evaluation of different knee arthroplasty systems was being undertaken. Data on the first 93 consecutive patients receiving a Scorpio (Stryker, Allendale, NJ) implant and the first 93 consecutively receiving a PFC (DePuy, Warsaw, IN) implant were reviewed. Four year revision rates and functional scores were recorded.
Results
Patient demographics were similar in both groups.
Six of ninety three Scorpio implants were listed for revision over the four year period (6%). Five of these were for aseptic loosening. Three further patients are currently being investigated for pain and have radiological evidence of loosening with no clinical evidence of infection. No PFC implants required revision in the four year period (p = 0.013).
There was no difference in Oxford Scores pre-operatively, or at 3 months, 1 year and 2 years post-operatively.
Discussion
There is a significant difference in revision rates between the two prostheses, and the revision rate of the Scorpio prosthesis is far higher than would be expected. The majority of these have been revised for aseptic loosening. Those prostheses surviving to four years had similar clinical outcomes. The reasons for this higher than expected revision rate in the Scorpio group require further exploration.
