Evaluating Failure Rates of Primary Quadriceps Tendon Repairs Across Different Surgical Techniques.

Background: Quadriceps tendon ruptures occur infrequently in the general population. Biomechanical data suggest advantages with the use of suture anchor fixation for major tendon repair. Clinical studies of quadriceps tendon repair have been limited to small case series.

Purpose: To evaluate clinical failure following primary quadriceps tendon repair with transosseous tunnel or suture anchor repair.

Study design: Cohort study; Level of evidence, 3.

Methods: The Military Health System Data Repository was queried to identify all adult patients who underwent primary quadriceps tendon repair in the Military Health System between 2014 and 2018. Patients were excluded if they had incomplete records, polytrauma, open injury, prior ipsilateral total knee arthroplasty did not undergo quadriceps tendon repair, or underwent revision repair. Follow-up was obtained by manual chart review of both orthopaedic and nonorthopaedic records, recording any evidence of ongoing knee issues. Univariate analysis was performed to determine associations between potential risk factors and repair failure. Multicollinearity was assessed between potential risk factors, and candidate variables were included in multivariate logistic regression models to determine independent risk factors for repair failure.

Results: Following application of inclusion/exclusion criteria, 245 knees in 234 patients were included. Mean age of the cohort was 52 years. Patients were predominantly male (223/234; 95%) and military retirees (143/234; 61%). Transosseous tunnel repair was the most frequently employed surgical technique (147/245; 60%), followed by suture anchor repair (78/245; 32%). Repair failure requiring revision surgery occurred in 11% of knees (27/245). Surgical-site infection following index surgery was associated with eventual rerupture (P = .02). There was no difference in failure rate between transosseous tunnel repair and suture anchor repair (12.2% vs 9.0%; P = .51). Among knees undergoing suture anchor repair, no difference in failure was found between knot-tying and knotless suture anchor fixation (P = .73).

Conclusion: We observed no difference in failure of primary quadriceps tendon repair between transosseous tunnel and suture anchor repair types or between the 2 main suture anchor implant subtypes (knotless vs knot-tying anchors). A greater than previously reported rerupture rate was observed, indicating the need for continued investigation into optimal surgical techniques.