Effect of Knee Brace on Frequency Spectrum of Ground Reaction Forces during Landing from Two Heights of 30 and 50 cm in Athletes with Anterior Cruciate Ligament Injury

The purpose of the present study was to evaluate the effect of knee brace on frequency spectrum of ground reaction forces during landing movement from two heights of 30 and 50 cm in athletes with anterior cruciate ligament injury.
A total of 15 athletes with ACL injury volunteered to participate in the study. The landing tests were performed from heights of 30 and 50 cm. Ground reaction forces were recorded before and after using knee brace making use of Bertec force platforms. Also, Wilcoxon test was used for statistical analysis.
The number of essential harmonics in medio-latral direction during brace condition decreased by 1.82% (P = 0.024). Also, the median frequency in anterior-posterior direction showed a significant increase of 195.46% during brace condition (P = 0.025).
The use of brace in anterior cruciate ligament injury athletes had the greatest effect on the essential number of harmonics along the medio-latral direction and median frequency in the anterior-posterior direction. The novel knee brace could be designed to reduce other components of ground reaction force frequency domain in injured athletes with aim of early return to sports competitions.