Phone 810.691.2002
Fax 810.743.4745
Email info@armourex.com
Ankle Shield™ Functionality
The Ankle Shield™ pad is a functional enhancement applied to a standard ankle tape job. It works by improving the leverage of the support structure with the tape.
In a typical ankle injury (Figure 1), torque to the foot/heel twists the ankle around the center of rotation (COR) of the ankle joint. This results in tension in the lateral ankle ligaments.
A typical ankle wrapping functions by stretching material over the lateral malleolus (outside ankle bone). The hope is that the tape will stop the ankle from rolling and injuring itself (Figure 2).
Biomechanics of rolled ankle injuries and prevention
The physics of an ankle injury is as follows: Torque equals the force times the perpendicular distance. T = FD⊥.
Leverage is measured as the distance from the center of the ankle joint to the structure resisting the rolling. Normally the structure that resists rolling is the fabric of the tape. In a perfectly functioning tape application, the torque of the inversion motion is offset perfectly by the torque provided by the tape. Unfortunately, most ankle wrappings do not function perfectly to prevent the injury to the ankle when it rolls. The Ankle Shield™ pad increases the capacity of a tape job to generate torque by enhancing its leverage (through added distance and material composition), thereby creating a counter lever which prevents/minimizes injury to the ankle (Figure 3).