Survivorship of Extensor Mechanism Allograft Reconstruction After Total Knee Arthroplasty

J Arthroplasty. 2017 Jan;32(1):183-188. doi: 10.1016/j.arth.2016.06.031. Epub 2016 Jun 29.

Abstract

Background: Extensor mechanism disruption remains a devastating complication after total knee arthroplasty. The purpose of this study is to describe the outcomes of extensor mechanism allograft (EMA) reconstruction in a large single-center case series.

Methods: Consecutive patients with a previous total knee arthroplasty undergoing extensor mechanism reconstruction using a fresh-frozen EMA tensioned in full extension were identified retrospectively from single-center institutional database (N = 25 patients, 26 knees; mean follow-up 68 months [range 22-113 months]). The primary outcome was initial allograft failure, defined as removal of the allograft or extensor lag >30 degrees at most recent follow-up.

Results: Sixty-nine percent (18/26) of knees had retained their initial allograft reconstruction at their latest follow-up despite reoperation rates of 58% (15/26). A younger age was significantly associated with failure of the initial allograft reconstruction. Knee Society Scores increased from 101 (38 standard deviation [SD]) to 116 (40 SD) at most recent follow-up for the group as a whole (P = .4). Patients undergoing a reoperation for any cause had lower Knee Society Scores (101 [SD 38] vs 138 [SD 32], respectively; P = .04) at most recent follow-up.

Conclusion: EMA reconstruction shows adequate overall intermediate-term survival; however, reoperation rates were high and associated with worse functional outcomes.

Keywords: extensor mechanism allograft; patellar tendon rupture; periprosthetic patellar fracture; quadriceps tendon rupture; revision total knee arthroplasty.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Allografts / statistics & numerical data*
  • Arthroplasty, Replacement, Knee / adverse effects*
  • Female
  • Humans
  • Knee Joint / surgery*
  • Male
  • Middle Aged
  • Postoperative Complications / etiology
  • Postoperative Complications / surgery*
  • Range of Motion, Articular
  • Reoperation / statistics & numerical data*
  • Retrospective Studies
  • Risk Factors
  • Treatment Outcome