Effects of Exercise-Based ACL Injury Prevention Interventions on Knee Motion in Athletes: A Systematic Review and Bayesian Network Meta-Analysis

OBJECTIVE: To compare the effectiveness of injury prevention programs (IPPs) for improving high-risk knee motion patterns in the context of reducing the risk of noncontact anterior cruciate ligament injury. DESIGN: Systematic review with Bayesian network meta-analysis. DATA SOURCES: PubMed, Embase, Web of Science, Cochrane Library, and the Cumulative Index to Nursing and Allied Health Literature were searched until September 10, 2023. ELIGIBILITY CRITERIA: We included randomized controlled trials involving athletes without prior anterior cruciate ligament injury. The trials had to provide data on peak knee flexion and valgus angles, obtained from 2-leg drop vertical jump, single-leg drop vertical jump, or side-step cutting test. RESULTS: The network meta-analysis synthesized data from 22 randomized controlled trials involving 878 participants, evaluating 12 different IPPs. Results of meta-analyses indicated that, in jumping tests, the external focus instructions (mean difference [MD] = 26; credible interval [CrI] = 7.5, 44; surface under the cumulative ranking curve [SUCRA] = 0.94) and internal focus of attention (MD = 19; CrI = 0.19, 37; SUCRA = 0.81) was effective for increasing peak knee flexion, and core stability training ranked first for reducing knee valgus (MD = −4.40; CrI = −7.7, −1.1; SUCRA = 0.96). None of the IPPs revealed statistically significant effects for the cutting test. CONCLUSION: The external focus instructions and internal focus of attention increased knee flexion, while core stability exercise reduced knee valgus in jumping tests. Intervention effects were inconsistent for cutting tests. J Orthop Sports Phys Ther 2025;55(2):123-136. Epub 20 December 2024. doi:10.2519/jospt.2024.12720