Lower Limb Asymmetry in Mechanical Muscle Function: A Comparison Between Ski Racers With and Without ACL Reconstruction

Date
2016
Journal Title
Journal ISSN
Volume Title
Publisher
Scandinavian Journal of Medicine and Science in Sports
Abstract
Due to a high incidence of anterior cruciate ligament (ACL) re-injury in alpine ski racers, the aim was to assess functional asymmetry in the countermovement jump (CMJ), squat jump (SJ) and leg muscle mass in elite ski racers with and without anterior cruciate ligament reconstruction (ACL-R). Elite alpine skiers with ACL-R (n=9; 26.2±11.8 months post-op) and uninjured skiers (n=9) participated in neuromuscular screening. Vertical ground reaction force during the CMJ and SJ was assessed using dual force plate methodology to obtain phase-specific bilateral asymmetry indices (AI) for kinetic impulse (CMJ and SJ phase-specific kinetic impulse AI). Dual X-Ray absorptiometry (DXA) scanning was used to assess asymmetry in lower body muscle mass. Compared to controls, ACL-R skiers had increased AI in muscle mass (P<0.001), kinetic impulse AI in the CMJ concentric phase (P<0.05) and the final phase of the SJ (P<0.05). Positive associations were observed between muscle mass and AI in the CMJ concentric phase (r=0.57, P<0.01) as well as in the late SJ phase (r=0.66, P<0.01). Future research is required to assess the role of the CMJ and SJ phase-specific kinetic impulse asymmetry index as a part of a multi-faceted approach for improving outcome following ACL-R in elite ski racers.
Description
Keywords
knee injury, verticle jump, injury prevention, rehabilitaion, return to sport
Citation
Jordan, M. J., Aagaard, P., & Herzog, W. (2015). Lower limb asymmetry in mechanical muscle function: A comparison between ski racers with and without ACL reconstruction. Scandinavian journal of medicine & science in sports, 25(3), e301-e309.