Proposed Topic (Most preferred): :
HA Young Investigators Session (Projects to be presented by HA staff who had joined HA for 10 years or less)
Authors (including presenting author) :
Tse YH(1)(3), Mok KM(2)(3), Chan YK(1), Yung SH(3)
Affiliation :
(1)Prosthetics and Orthotics Department, Prince of Wales Hospital, (2)School of Interdisciplinary Studies, Lingnan University, (3)Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong
Introduction :
Team ball-sports involved repeated landings have a high incidence of non-contact ACL injuries. However, the correlation between orthoses, ACL deficient knee, and drop-landing has not been detailly clarified. Therefore, this study investigates the acute biomechanical effects of a functional knee brace and medial arch support on ACL deficient knees in drop-landing.
Objectives :
To examine the acute biomechanical effects of a functional knee brace and medial arch support on patients with ACL deficient knee in drop-landing.
Methodology :
Ten recreational athletes (n=10) with non-operated ACL deficient knees (unilateral grade II or III) were recruited to participate in this study at Prince of Wales Hospital in Hong Kong. Subjects were provided a functional knee brace and 2 different pairs of insoles. They were instructed to have 20 dynamic drop-landing trials from a 0.4 m height for 4 testing conditions (Table 1). Biomechanical data were captured, and a one-way analysis of variance was conducted.
Result & Outcome :
For the combinational use of medial arch support and functional knee brace, the smallest knee valgus moment was observed and there was no significant difference when comparing with the functional knee brace. It represented that the functional knee brace would be the key element which contributed to the significant influence on knee valgus moment. Besides, although the moment value was clinically lessened after the medial arch support was inserted, no statistically significant difference was found.
Knee bracing resulted in greater knee flexion angle and the force added on the ACL could be lessened during the peak of knee axial compression. It was because the increasing knee flexion diminished the tibial anterior shearing force that the risk of suffering from non-contact ACL injuries could be potentially eliminated.
To conclude, the functional knee brace could reduce the risk factors of non-contact ACL injury and offer additional stability to the ACL impaired knee during drop-landing. However, insoles with medial arch support did not show any significant influence in this study.
