Generalized joint hypermobility and risk of lower limb joint injury during sport: a systematic review with meta-analysis.

BACKGROUND Generalized joint hypermobility is a highly prevalent condition commonly associated with joint injuries. The current literature has conflicting reports of the risk of joint injury in hypermobile sporting participants compared with their nonhypermobile peers. Systematic reviews have not been conclusive and no meta-analysis has been performed. PURPOSE This review was undertaken to determine whether individuals with generalized joint hypermobility have an increased risk of lower limb joint injury when undertaking sporting activities. STUDY DESIGN Systematic review with meta-analysis. METHODS Studies were identified through a search without language restrictions of PubMed, CINAHL, Embase, and SportDiscus databases from the earliest date through February 2009 with subsequent handsearching of reference lists. Inclusion criteria for studies were determined before searching and all included studies underwent methodological quality assessment by 2 independent reviewers. Meta-analyses for joint injury of the lower limb, knee, and ankle were performed using a random effects model. The difference in injury proportions between hypermobility categories was tested with the z statistic. RESULTS Of 4841 identified studies, 18 met all inclusion criteria with methodological quality ranging from 1 of 6 to 5 of 6. A variety of tests of hypermobility and varied cutoff points to define the presence of generalized joint hypermobility were used, so the authors determined a standardized cutoff to indicate generalized joint hypermobility. Using this criterion, a significantly increased risk of knee joint injury for hypermobile and extremely hypermobile participants compared with their nonhypermobile peers was demonstrated (P < .001), whereas no increased risk was found for ankle joint injury. For knee joint injury, a combined odds ratio of 4.69 (95% confidence interval, 1.33-16.52; P = .02) was calculated, indicating a significantly increased risk for hypermobile participants playing contact sports. CONCLUSION Sport participants with generalized joint hypermobility have an increased risk of knee joint injury during contact activities but have no altered risk of ankle joint injury.