Upper Extremity Biomechanics Of A Back Handspring In Young Female Gymnasts

BACKGROUND: Gymnastics is one of the rare sports which uses the upper extremity (UE) as a weight bearing surface. However, how the UE including wrist, elbow, and shoulder is used in fundamental skill such as backhand spring is understudied. PURPOSE: To assess wrist, elbow, and shoulder joint angles at sagittal plane in a backhand spring movement among young female gymnasts. METHODS: A cross-sectional, controlled laboratory study was used. Twenty-three female gymnasts (mean ± standard deviation; age = 12.3 ± 1.5 years; height = 143.4 ± 7.6 cm; body mass 37.7 ± 6.6 kg) performed back handsprings. Three-dimensional upper extremity joint angles and moments were assessed using a 10-camera, marker-based motion analysis system (240fps) and dual force plates (1200 Hz). The back handspring was broken down to phase 1 and 2. Phase 1 is the first part of the back handspring and ends when the gymnast’s contact is roughly 0% to 49% with her hands on the force plate. Phase 2 starts when the gymnast’s contact is 50% to 100% on the force plate, and finishing by standing upright. Descriptive statistics including mean, standard deviation, and 95% confidence interval (95%CI) was used. RESULTS: During phase 1, mean wrist joint angles ranged from 41.8 ± 10.9 (37.0, 46.5) to 68.1 ± 10.5 (63.6, 72.7) degrees of extension. Mean elbow joint angles ranged from 16.7 ± 3.5 (15.2, 18.3) to 42.2 ± 12.8 (40.7, 51.7) degrees of flexion. Mean shoulder joint angles ranged from 132.7 ± 18.0 (124.9, 140.5) to 173.2 ± 7.6 (169.9, 176.4) degrees of flexion. During phase 2, mean wrist joint angles ranged from 26.6 ± 11.8 (21.5, 31.7) and 60.8 ± 9.9 (56.5, 65.0) degrees of extension. Mean elbow and shoulder joint angles ranged from 15.1 ± 5.4 (12.8, 17.5) to 41.6 ± 13.5 (35.8, 47.4) and 125.2 ± 14.3 (119.1, 131.4) to 140.0 ± 11.9 (134.9, 145.1) degrees of flexion, respectively. CONCLUSIONS: This is one of the first studies to investigate the joint angles of the UE while performing a back handspring. Clinicians can use this biomechanical data when assessing the back handspring and considering return-to-sport benchmarks in young female gymnasts.