The Transradial Anatomically Contoured (trac) Interface: Design Principles and Methodology

Although there are many variations of the self-suspending transradial (below elbow) level interface, they generally can be divided into two styles: the Muenster-type and Northwestern University Supracondylar Suspension Technique designs. Variations of these styles often represent practitioner interpretation and an evolutionary process to enhance comfort, stability, and suspension. The Transradial Anatomically Contoured (TRAC) interface incorporates design elements from both the Muenster and Northwestern interfaces with more aggressive contouring of the anatomy to maximize load tolerant areas of the residual limb, as demonstrated by the radiologic analysis in this text. In the medial/lateral plane, the interface focuses the compression anterior and slightly inferior to the epicondyles, specifically about the radial head on the lateral aspect. In addition, on the anterior/posterior plane, suspension is achieved by precisely directed compression into the cubital fold and supra-olecranon region. A critical element in the successful design of the Transradial Anatomically Contoured interface is extensive anatomic contouring of the antecubital region. The combined effects of medial/lateral and anterior/posterior compression along with contouring of the musculoskeletal structure of the residuum allow enhanced comfort, suspension, and stability throughout an increased range of motion.