A Three-dimensional Kinetic Comparison Of The Effects Of Three Prophylactic Ankle Devices On The Lower Extremity

Abstract

With the rise in cost of athletic tape many sports medicine programs are switching to reusable ankle support devices. Few studies of the effects of these devices have placed subjects in weight bearing situations, and fewer still have simulated actual game or practice conditions. Therefore, the purpose of this study was to compare the effects of three brace designs on ankle range of motion and the attenuation of forces experienced while landing from a volleyball block jump. The braces used for this comparison were Swede-O Universal Athletic, Aircast Sport-Stirrup, and Active Ankle Trainer. Twelve female intercollegiate volleyball players, mean age of 20.08 +/- 2.0 years, mean height of 172.94 +/8.02 cm, and mean mass of 67.84 +/ - 8.5 kg, were randomly assigned to one of three braces being tested. Subjects performed volleyball block jumps in a simulated practice setting under three conditions, non-braced, immediately after brace application, and immediately following a one and a half hour practice. All subjects wore the same type of shoe during data collection. Two high speed cameras were used to collect three-dimensional coordinate data for one jump per condition for each subject. Ground reaction forces were collected using a Kistler force plate. Analysis of the angular data included relative knee angles and absolute ankle angles. Results of angular data did not vary across brace types and conditions. Therefore, similarity of jump execution seems valid. Compressive forces at the ankle remain consistent across brace and condition. Generally, these compressive forces varied from two to three body weights. The inversion and eversion force patterns at the ankle were consistent across conditions for two of the brace types. The compressive forces at the knee were also uniform across brace types and conditions. Variations observed between brace types and under different conditions suggested different advantages and disadvantages for the three braces analyzed in this study.