Instability after total knee arthroplasty with the Miller-Gallante II total knee: 5- to 7-year follow-up

A consecutive series of 64 posterior cruciate-retaining hybrid total knee arthroplasties in 50 patients were reviewed with an average 57-month follow-up. Seven patients died or were lost to follow-up. One patient was revised for infection in the early postoperative period, and there were no cases of aseptic loosening. Four revisions were performed for recurrent effusions and progressive instability at a mean of 55 months postoperatively. There were statistically significant correlations between manual stability testing (anteroposterior, mediolateral, and pivot shift) and Hospital for Special Surgery and Knee Society scores. At intermediate follow-up, the Miller-Gallante II total knee arthroplasty is functioning well except in a subgroup of patients with progressive instability resulting from a combination of patient and implant factors.