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NO ASSOCIATION BETWEEN STATIC AND DYNAMIC POSTURAL CONTROL AND ACL INJURY RISK AMONG FEMALE ELITE HANDBALL AND FOOTBALL PLAYERS

Background Little research exists quantifying balance measures as potential risk factors for ACL injury. Objective To assess whether static and dynamic postural control were associated with an increased risk for ACL injury in female elite handball and football players. Design Prospective cohort study. Participants From 2007 through 2015, 838 female premier league players participated in pre-season testing and were prospectively followed for ACL injury risk. Assessment of risk factors and main outcome measures At baseline, we recorded player demographics, playing experience, ACL and ankle injury history. We measured the mean velocity of COP in medio-lateral (ML) and anterior-posterior (AP) directions (mm/s), as well as the area of the 95% confidence ellipse area (mm2). We used the Star Excursion Balance Test to measure anteromedial, medial and posteromedial reach directions (cm). To examine the stability of postural control measures over time, we examined long-term and short-term reproducibility. We followed a pre-defined statistical protocol with logistic regression models, one for each of the proposed risk factors. Results A total of 55 (6.6%) players (age: 20±4 yrs; height: 171±7 cm; body mass: 68±9 kg) sustained a non-contact ACL injury after baseline testing (1.8±1.8 yrs). When comparing height and leg-length normalized balance measures between injured and uninjured players in univariate analyses, none of the variables were statistically associated with an increased risk of ACL rupture. Short- and long-term reproducibility of the selected variables was poor. Players with a previous ACL injury had a 3-fold higher risk of sustaining a new ACL injury compared to previously uninjured players (OR 2.9, CI 1.4 to 5.7). Conclusions None of the static and dynamic postural control measures examined were associated with increased ACL injury risk among female elite handball and football players. Hence, the variables included in the current investigation cannot be used to predict injury risk.