Abstract
Background
Extensor mechanism disruption following total knee arthroplasty is a destructive complication with poor outcomes. Presently, limited data exists regarding the direct repair therapy and long-term outcomes. This study was to evaluate the clinical results and complications of direct repair therapy, and compare it with similar studies to determine whether there is a better treatment.
Methods
During the period of 2008 to 2020, 31 patients underwent direct repair for an extensor mechanism disruption after total knee arthroplasty (15 patellar fractures, 9 patellar tendon disruptions, and 7 quadriceps tendon disruptions). Mean follow-up was 4.9 years. Demographic, operative, and clinical data were collected. The following statistical methods will be employed to analyze the data: descriptive statistics, paired t test, and the Kaplan-Meier method.
Results
For all 31 patients underwent direct repair for extensor mechanism disruption, 6 patients failed : 2 knees (6%) of infections and 4 knees (13%) of re-rupture. ROM was 94.1° ± 15.7° preoperatively to 73° ±52° postoperatively, average extensor lag reduced from 45° to 20.2° at follow-up, and the WOMAC and HSS averaged 65 and 72 points. The Kaplan-Meier estimated survivorship with failure for complications as the end point was 81% (95% confidence interval [95% CI], 42.7% to73.3%) at 12 years.
Conclusion
Direct repair of the extensor mechanism disruption is not an ideal therapy, it’s actually ineffective for the recovery of knee joint function in patients, and will remain severe knee extension lag. No matter which part of the extensor mechanism disruption, direct repair should not be the preferred treatment
Quadriceps Tendon Rupture Following Total Knee Arthroplasty