Background There is controversy surrounding the early use of open-kinetic-chain (OKC) quadriceps-strengthening exercises following anterior cruciate ligament reconstruction (ACLR) due to the belief that increased strain on the graft could cause damage. Objectives To determine whether OKC quadriceps exercises result in differences in anterior tibial laxity, strength, function, quality of life, or adverse events in the ACLR population, when compared to closed-kinetic-chain (CKC) quadriceps exercises. Methods Seven electronic databases (MEDLINE, Embase, AMED, CINAHL, SPORTDiscus, PEDro, and the Cochrane Central Register of Controlled Trials) were searched through April 2017. A systematic review with meta-analysis was conducted on randomized controlled trials comparing OKC versus CKC exercises following ACLR. Outcomes of interest were tibial laxity, strength, and function. A methodological quality assessment of the included studies was completed, and the results were synthesized using meta-analysis and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Results Ten studies were included in the review. The meta-analysis demonstrated low- to moderate-quality evidence of no between-group differences in anterior tibial laxity, strength, or patient-reported function at any time point. Meta-analysis was unable to be performed for functional outcomes. Conclusion There was limited to moderate-quality evidence of no difference in anterior tibial laxity, strength, patient-reported function, or physical function with early or late introduction of OKC exercises in the ACLR population, when compared to CKC exercises, at all follow-up time points. Level of Evidence Therapy, level 1a. J Orthop Sports Phys Ther 2018;48(7):552-566. Epub 23 Apr 2018. doi:10.2519/jospt.2018.7656.
Keywords: knee; physical therapy; rehabilitation.