A four-experiment examination of ankle kinetics, kinematics and lateral ligament strains during different conditions; an examination using musculoskeletal simulation.

Abstract

Purpose
First, to provide insight into the differences in ankle kinetics, kinematics and lateral ligament strain between males and females during functional sports movements. In addition this study explores the prophylactic efficacy of different footwear and bracing modalities.

Methods
Experiment 1 examined male and female athletes performing run, 45° cut and one-legged hop movements, experiment 2 observed court, energy return and trainer footwear conditions during a change of direction task, experiment 3 examined high-cut, low-cut and trainer footwear conditions in a change of direction, run, 45° cut and vertical jump movements and experiment 4 explored an ankle sleeve and an ankle brace during a change of direction movement. In each experiment ankle kinetics and ligament strain were measured using a musculoskeletal simulation approach.

Results
Experiment 1 indicates that males exhibited increased inversion velocity (male = 260.39 and female = 219.18°/s) in the cut movement as well as enhanced peak posterior force (male = 2.24 and female = 1.35BW), anterior talofibular ligament (ATFL) strain rate (male = 266.77 and female = 133.16%/s). Experiment 2 showed that both calcaneofibular ligament (CFL) and posterior talofibular ligament (PTFL) strain velocities were greater in the court footwear (CFL = 90.86 and PTFL = 151.45%/s) compared to the trainer (CFL = 69.07 and PTFL = 119.57%/s). Experiment 3 showed in the run movement anterior talofibular ligament (ATFL) strain was enhanced in the trainer (7.86%) compared to the high (3.61%) and low (5.87%) conditions and the trainer (8.14%) compared to the low footwear (5.39%) for the cut movement. PTFL strain velocity was greater in the high footwear (188.01%/s) compared to the trainer (175.60%/s) during the run movement and in both high (221.55%/s) and low (220.29%/s) footwear compared to the trainer (202.05%/s) during the cut. Experiment 4 revealed that PTFL strain was greater in the sleeve condition (17.05%) compared to the ankle brace (15.42%).

Conclusion
This study provides insight into the potentially increased incidence of lateral ankle ligament sprain injuries in males, whilst also highlighting the prophylactic efficacy of ankle braces in attenuating the ankle strain mechanisms linked to the aetiology of lateral ankle ligament injuries.