Abstract
INTRODUCTION: The quadriceps tendon (QT), which is formed by the confluence of the vastus intermedius, vastus lateralis, vastus medialis, and rectus femoris muscles plays a vital role in knee extension, hip flexion, and lower extremity mobility. The purpose of this systematic review is to evaluate post-operative outcomes, range of motion, and complications in patients who undergo quadriceps tendon repair. METHODS: In accordance with PRISMA guidelines, PubMed, Embase, and Cochrane Library databases were searched in August 2024 for studies published after 2004. Studies were included if they evaluated patients who underwent quadriceps tendon (QT) repair with any technique, were prospective or retrospective studies, and reported outcomes or complications. Studies not written in English or that did not evaluate complications or outcomes following QT repair were excluded. RESULTS: The initial screen identified 662 studies, 6 of which were included. There were three retrospective case series, two retrospective cohort studies, and one prospective non-randomized study. Each study had low risk of bias. A total of 324 patients (89.5 % male) were included. Mean age across studies ranged from 32.0 to 65.8 years. Five studies pertained to patients over 50 years old; one study focused on patients under age 40. Otherwise, there were similar patient demographics across studies. Fixation techniques included transosseous tunnels, suture anchors, simple sutures, and adjustable cortical fixation. Mean post-operative Lysholm scores ranged from 85.4 to 94.0 (range 30-100). Full extension was reached by 88.7-100 % of patients. Mean knee flexion across studies ranged from 124.3 to 133.0°, with overall ranges of 110-150°. Re-rupture or failure occurred in 0-15.4 % of patients. Other complications included VTE (0-15.4 %), arthrofibrosis (0-7.7 %), infection (0-2.0 %), paresthesias over the anterior knee (0-13.2 %), and wound dehiscence (0-7.7 %). CONCLUSIONS: Quadriceps tendon repair restores extensor mechanism function in patients with a low complication rate. There are no differences in outcomes or complications based on operative technique used. Decisions regarding operative technique should be tailored to individual patient characteristics and surgeon preferences with special consideration of medical comorbidities and systemic diseases that can affect tissue quality and post-operative healing. LEVEL OF EVIDENCE: Level IV, systematic review of level II- IV studies.