Landing Patterns in Subjects with Recurrent Lateral Ankle Sprains

Abstract

Introduction The most common symptoms after ankle sprains were chronic ankle instability, proprioception defect and probable neuromuscular adaptation. The purpose of this study was to identify the normal landing pattern using detailed biomechanical analysis including analysis of the kinematics and ground reaction force, and to compare the landing pattern in the subjects with recurrent ankle sprain and normal subjects. METHODS Ten male adults were recruited in this study (5 subjects with recurrent lateral ankle sprains group, 5 subjects with normal control group). All subjects would be asked to perform maximal standing jumps and drop landing from 3 platforms with different heights (0.37 m, 0.67 m, & 0.97 m, respectively). Those movements were collected by VICON 512 (Oxford Metrics, UK) motion analysis system and the kinematics was analyzed using self making software with MATLAB. The ground reaction force of both lower limbs was recorded by two AMTI force platforms, and the kinetic data were calculated with inverse dynamics. RESULTS In the different landing height, the main differences of kinematics were the maximum flexion angles of hip and knee joints in normal landing patterns and the flexion angles increased with the landing height, as well as the flexion of pelvis, hip abduction, and knee external rotation in the subjects with recurrent ankle sprains. When compare those two groups, the landing pattern in the subjects with recurrent ankle sprain was significant smaller than normal subjects in knee flexion (65.71°±6.43° vs. 70.19°±13.76°) and hip flexion (34.15°±5.42° vs. 42.54°±10.07°). The time to maximum angles in ankle dorsiflexion and foot pronation were also quite different between these two groups. The maximum vertical ground reaction force in sprain group was significant smaller than normal group. CONCLUSION In this study, we have revealed the adaptation of performing drop landing in the individuals with recurrent ankle sprains. It could be considered as a recommendation of the rehabilitation..