The effect of open- versus closed-kinetic-chain exercises on anterior tibial laxity, strength, and function following anterior cruciate ligament reconstruction: a systematic review and meta-analysis

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 moderatequality 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 moderatequality 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