Isometric Strength of Rearfoot Inversion and Eversion in Nonsupported, Taped, and Braced Ankles Assessed by a Hand-Held Dynamometer

Abstract

Previous studies have reported a reduction of athletic performance while wearing ankle orthoses. The present study investigated whether or not this observed reduction in performance was the result of a restriction of the associated muscles by the orthoses. Specifically, 36 male undergraduate students participated in this study to compare the effects of unsupported, nonelastic adhesive-taped, and Swede-O, New Cross, Air-Stirrup, and STS braced ankles on isometric strength of rearfoot inversion and eversion as assessed by a hand-held dynamometer. Subjects were stabilized in a seated position so that lower limb movement was restricted to the ankle. Each subject performed isometric inversion and eversion contractions under all six ankle conditions with the dominant foot. The isometric force was recorded from each of three trials during rearfoot inversion and eversion under each support condition. One-way repeated measures ANOVAs failed to detect any significant differences between the six testing conditions for inversion and eversion for both mean and peak force values. No alterations were observed in the isometric forces recorded during rearfoot inversion and eversion, thus, indicating that the orthoses did not constrict the lower leg musculature. These results suggest that, when selected by the clinician, any brace used in this study would not be detrimental to lower leg strength. J Orthop Sports Phys Ther 1992;15(5):229-235.