Associations between musculoskeletal injury and selected lower limb biomechanical measurements in female amateur ballet dancers

Abstract

Background: Classical ballet is an art form that seems graceful on the surface. However, beneath the disguise of beauty and ease lies an extremely physically demanding activity that calls for dedication, strength and perseverance. Ballet requires a specific body type and precise techniques, which predispose the dancer to musculoskeletal injury. Although a few studies have been conducted to investigate biomechanical factors as risk factors for injury in ballet dancers, few have included amateur ballet dancers and a range of biomechanical factors. Objectives: This study aimed to determine characteristics of ballet-related injury in amateur ballet dancers in the greater Durban area; to measure and record lower limb biomechanical measurements of these dancers; and to identify associations between the biomechanical measurements and characteristics of injury in the population. Method: A quantitative, questionnaire-based survey with biomechanical measurements was conducted on 21 amateur ballet dancers in the greater Durban area. Statistical analysis included the description of categorical variables using frequency and percentages in tables and bar charts. Continuous variables were summarised using mean, standard deviation and range, or median and range as appropriate. Independent Sample T-tests were used to compare biomechanical measurements between two independent groups. A p value <0.05 was considered as statistically significant. Pearson’s correlations and ANOVA testing were also used. Results: The period prevalence of ballet-related injury over the last 2 years was found to be 62% and the point prevalence 38%. There were 37 total previous injuries, most of which occurred in the hamstring (24%). Most of the worst previous injuries were reported to have occurred in the low back (31%). Most of the worst previous (70%) and current (93%) injuries occurred over time. The worst previous injuries reported ranged from mild to severe in severity, while the worst current injuries reported ranged from mild to moderate. Significant associations were found between right weight-bearing ankle dorsiflexion and previous injury; right weight-bearing ankle dorsiflexion and current injury; ‘functional turnout’ and onset of injury; right non weight-bearing ankle dorsiflexion and onset of injury; and ‘compensated turnout’ and onset of injury. Conclusion: The results suggest a significant association between musculoskeletal ballet-related injury and reduced weight-bearing ankle dorsiflexion; between injuries that occur over time (overuse injuries) and decreased ‘functional turnout’; and between overuse injuries and decreased non weight-bearing ankle dorsiflexion. These findings may help identify risk factors for injury in ballet dancers and contribute towards preventing ballet-related injury.