Background: Risk factors for anterior cruciate ligament reconstruction (ACLR) construct failure have been studied extensively. However, while some studies account for variables such as activity level, construct types, preoperative physical therapy, or patient demographics individually, comprehensive studies that control for all these factors simultaneously are scarce.
Hypothesis: By utilizing a robust multivariable analysis, the factors associated with an increased risk of ACLR construct failure can be determined.
Study design: A single-center, retrospective cohort study was conducted, encompassing patients who underwent primary ACLR between January 2015 and December 2021.
Level of evidence: Level 3.
Methods: Eligible patients were identified using the current procedural terminology code 29888. Datapoints collected included demographics, body mass index, injury setting, graft type, graft size, fixation type, concomitant ligamentous injuries, notchplasty, operating surgeon, preoperative physical therapy, and instances of construct failure. The prevalence of construct failure was analyzed using chi-square tests, comparing across all graft and fixation type combinations in ACLR procedures. A mixed-effects logistic regression model was utilized to account for the potential influence of all relevant variables on construct failure.
Results: Out of 1245 patients, the construct failure rate was 5.62% (n = 70), with >95% of patients having >2 years of retrospective follow-up (95% CI [4.34-6.90]), with a median failure time of 502.5 days (interquartile range [265.5-1033.8]). The mixed-effect logistic model identified preoperative physical therapy (odds ratio, 0.404, 95% CI [0.193-0.844]) as the only significant factor in possibly preventing construct failure.
Conclusion: Contrary to conventional focus on graft and fixation types, this study emphasizes the protective role of preoperative physical therapy in reducing ACLR construct failure.
Clinical relevance: Our findings suggest the integration of preoperative physical therapy in clinical practices to mitigate ACLR construct failure risk, warranting further exploration in future studies.
Keywords: ACLR construct failure; mixed-effects logistic regression; preoperative physical therapy; retrospective cohort analysis.