Revision extensor mechanism allografting after total knee arthroplasty

This study analyzed the outcomes of revision extensor mechanism allografting (EMA) in 8 patients with failures of previous EMA after total knee arthroplasty. Fresh-frozen allografts were used. Knee Society Clinical Rating System (KSS) scores were used to measure clinical outcomes, with special attention given to presence of extensor lag and assistive ambulatory devices. Patients were observed for an average of 3.1 years. Two patients were considered failures due to infection within the first postoperative year of the revision EMA. In the remaining 6 patients, the average KSS score at most recent follow-up showed no improvement when compared with preoperative scores. Revisions of the failed EMA resulted in a high incidence of functional limitations, which continue to deteriorate over time.