A comparison of the Sport Stirrup, Malleoloc, and Swede-O ankle orthoses for the foot-ankle kinematics of a rapid lateral movement.

Little information exists about the efficacy of various brace designs to restrict inversion during lateral movements. The purpose of the study was to determine whether semi-rigid stirrup (AirCast Sport Stirrup), semi-rigid modified stirrup (Malleoloc), or a soft, sleeve design (Swede-O) brace varied in their abilities to restrict inversion without hindering plantar/dorsiflexion when a lateral cutting movement is performed compared to a no-brace condition (No-Br). Nineteen volunteers who had previously sprained their right ankles performed 10 sideward cutting trials/brace condition. Based on kinematic data, captured using high-speed cameras, none of the braces restricted inversion compared to the No-Br condition. Plantar flexion was inhibited for all braces, and less dorsiflexion was exhibited for the Swede-O. For three participants, greater toe-in landings were observed for the Swede-O. Based on chi-square analyses, the participants rank of braces for stability and overall performance in decreasing order: Malleoloc, AirCast, Swede-O. It was concluded that the participants may have exhibited injury avoidance behavior during conditions perceived to be less stable, thereby reducing inversion when wearing no brace or the Swede-O brace. It also is tenable that the motion of the shoe was influenced by the presence of the braces, hence, no inversion restriction was observed.