Development of a measurement device and a lower leg phantom for standardized biomechanical testing of ankle braces

Abstract

Orthoses are frequently used for the prevention and rehabilitation of ankle injuries. A diverse variety of products exists, but objective information comparing their mechanical support is often lacking. To objectively and reproducibly quantify the mechanical supportive effect of ankle braces, a highly precise measurement device for recording passive joint stiffness was developed alongside a lifelike two-axis silicone phantom. Because biomechanical in vivo tests are subject to strong inter-individual fluctuations, the use of measurement phantoms is indispensable for isolating purely mechanical stabilization properties. The measurement device was validated using a standardized mechanical spring phantom, while the two-axis silicone phantom was calibrated and validated against native in vivo stiffness values derived from a study of healthy subjects. The results demonstrate that the combination of the precise measurement device and the twoaxis phantom accurately simulates the biomechanical behavior of the human ankle joint, thereby enabling standardized, subject-independent orthosis testing.