STUDY DESIGN: Controlled laboratory testing using a single-group, prospective, repeated-measures design. OBJECTIVES: To compare the material properties of a hyperelastic athletic tape to a conventional tape and to compare the passive ankle support of these tapes before and after exercise. BACKGROUND: The near-linear material properties of conventional athletic tape may interfere with ankle motion, resulting in reduced athletic performance. Conventional athletic tape is also known to lose much of its initial support during exercise. It was assumed that a tape constructed of Kevlar fibers embedded in a silicon matrix would possess hyperelastic material properties that would improve ankle support. METHODS: A tensile testing machine was used to determine the tensile material properties of 11 samples of conventional and hyperelastic tape. The ankles of 11 young, healthy athletes were taped, one ankle with conventional tape and the other ankle with hyperelastic tape. The passive ankle support of each tape was measured with an instrumented linkage (the ankle flexibility tester) before and after 30 minutes of exercise. RESULTS: The composite tape had a significantly higher load to failure than the conventional tape. It had significantly lower initial stiffness and higher late stiffness than conventional tape, thus demonstrating highly hyperelastic behavior. The hyperelastic tape maintained a significantly higher portion of its support during the 30 minutes of exercise than the conventional tape. CONCLUSIONS: Composite athletic tape with highly hyperelastic properties can be constructed and maintains a larger portion of its support during short-duration exercises (less than 30 minutes) than conventional athletic tape.

J Orthop Sports Phys Ther 2011;41(12):961-968. doi:10.2519/jospt.2011.3476

KEY WORDS: anterior talofibular ligament, brace, calcaneofibular ligament, inversion sprain, ligament

Studies of the passive support provided by ankle braces have focused primarily on inversion support. The goal of this study was to develop a technique to measure the support provided by ankle braces in all rotational directions and to use this technique to compare four common braces (Ascend™, Swede-O™, Aircast™, and Active Ankle™) For this purpose, a 6 degrees-of-freedom linkage was used to measure the flexibility of the ankle complex in 10 healthy subjects. Each subject was tested without brace support and with each of the 4 braces. Testing was repeated on each subject on 2 different occasions. The angular displacement at specified moment values and the 4 segmental flexibility values obtained from the loading portion of the moment-angular displacement data were used in the data analysis. Repeated measure analysis of variance followed by a Student Neuman-Keuls test at p < 0.05 was performed. This statistical analysis was used to identify significant differences among the braces and differences between each brace and the no brace condition. Each of the 4 braces provided significant support in inversion, eversion, and internal rotation, but the amount of support varied significantly among the braces. In external rotation, only the stirrup braces provided significant support. The braces also varied significantly in the amount of interference with dorsiflexion and plantar flexion. Clinicians may be assisted by objective data on the amount and nature of passive support when prescribing braces to their patients.

J Orthop Sports Phys Ther. 1997;26(6):299-309.

Key Words: ankle, braces, passive support