Joint Hypermobility as a Predictor of Mechanical Loading in Dancers

Abstract

Context:Dance requires the performance of complex movements that may exceed normal anatomical range. However, in hypermobile individuals, this may have implications for injury and performance.Objectives:The aim of the study was to investigate the efficacy of the Beighton score (BS) in predicting mechanical loading in dancers in hypermobile and nonhypermobile dancers with consideration of accelerometer placement and lumbar flexion hypermobility.Design:Cohort study, clinical measurement.Setting:University.Participants:A total of 34 dancers had their joint hypermobility assessed by the BS. Participants completed the Dance Aerobic Fitness Test with a global positioning device incorporating a triaxial accelerometer located at the cervico-thoracic junction (C7) and one at the midbelly of the gastrocnemius.Main Outcome Measures:Accelerometry data were used to calculate PlayerLoad total, PlayerLoad medial-lateral, PlayerLoad anterior–posterior, and PlayerLoad vertical. Physiological response was measured via heart rate and fatigue response by rate of perceived exertion.Results:The total BS was a poor predictor of all mechanical loading directions with PlayerLoad anterior-posterior C7 (r = .15) and PlayerLoad total lower limb (r = .20) the highest values. Multiple linear regression was a better predictor with values of C7 (r = .43) and lower limb (r = .37). No significant difference existed between hypermobile and nonhypermobile subjects for mechanical loading values for all stages of the Dance Aerobic Fitness Test and for heart rate and fatigue responses.Conclusions:The BS is not a good predictor of mechanical loading which is similar in hypermobile and nonhypermobile dancers for all levels of the Dance Aerobic Fitness Test. Mechanical loading and fatigue responses are similar between hypermobile and nonhypermobile dancers.