UBC Theses and Dissertations
The role of functional knee bracing in a dynamic setting Rishiraj, Neetu
The controversy over functional knee bracing still lingers. Although there is ample literature available on both the possible positive and negative concerns of utilizing a functional knee brace, there is very little information available on functional knee bracing in a dynamic setting. The purposes of this study were to evaluate the effect of functional knee bracing on athletic performance during dynamic testing in a non-injured knee joint and to measure the effects of functional knee bracing (under dynamic testing) on an Anterior Cruciate Ligament (ACL)--deficient knee. A total of 60, 30 non-injured and 30 injured, subjects were tested with and without a functional knee brace. Each subject performed five functional tests—10 meter dash, figure-of-eight run, slalom run, hop test, and running down the stairs test. Each subject performed each test 8 times—two submaximal effort trials, followed by 6 trials (3 trials with and 3 trials without a brace) at maximal effort. A 2X3, repeated measures on both factors, ANOVA was conducted to determine the results during the accommodation phase. A single factor ANOVA analysis was performed on the best performance measures after accommodation had occurred to the functional knee brace. Furthermore, a correlation analysis was conducted between knee joint laxity of injured subjects and their performance levels. During the accommodation phase, the non-injured, braced group had statistically significant inferior performances (when compared to the noninjured, non-braced group) in the 10 meter dash, figure-of-eight, and the slalom tests and statistically superior performance in the hop test. In the running down the stairs test no statistically significant difference was noted between the two groups. However, once the subjects had accommodated to the brace (best performance) no statistically significant difference was noted between the non-injured, braced and the non-injured, non-braced groups for any test. As expected, during the accommodation phase, the injured, braced group performed statistically significantly better than the injured, non-braced group. However, after accommodating to the functional knee brace, an analysis of best performance data found no statistically significant difference between the two groups. A strong correlation was not evident between the injured athlete's knee joint laxity and performance levels. This study provides evidence that performance levels of non-injured, braced individuals is either only marginally hindered or is enhanced during the accommodation period when compared with non-injured, non-braced individuals. Once non-injured, braced individuals have accommodated to a functional knee brace they either perform at the same level or they outperform non-injured, non-braced subjects. These findings are an important consideration when considering a functional knee brace for prophylactic purposes. For injured individuals, performance levels are enhanced when a functional knee brace is utilized.