Biomechanical Assessment and Treatment in Lower Extremity Prosthetics and Orthotics: A Clinical Perspective

Biomechanics is a term that is widely used by physicians, prosthetists, or-thotists, and physical therapists to describe the mechanics of human loco-motion. It is a subject that involves many fields of knowledge, including anatomy, kinesiology, neurophysiology, mechanics, physics, and mathemat-ics. Volumes have been written on the subject, but even some experts admit, ‘‘Despite our fascination and years of scientific inquiry, we still do not know how we manage to get from point A to point B in an upright position. Con-trolling bipedal locomotion is not an easy task’ ’ [1]. The use of a prosthesis or an orthosis for locomotion adds an additional mechanical element to the study of biomechanics; as a result, the bio side of the equation representing the biomechanics of human locomotion interfaces with the mechanical side of the equation representing the prosthesis or or-thosis. The sum of this equation is a complete biomechanical system repre-sented by the patient; bio-mechanical treatment is required. To provide comprehensive treatment, the prosthesis or orthosis must be-come an integral part of that treatment; however, as mechanical devices, they also are products. In this context, they have limited value. Although these devices are used in treatment, this does not automatically imply that they are truly a part of treatment. Treatment is a term most associated with physical therapy. The therapist provides physical treatment, whereas Phys Med Rehabil Clin N Am 17 (2006) 203–243the prosthetist/orthotist provides the device. The mechanical device is a sys-tem composed of materials and technology. Design, fabrication, fit, and alignment also are part of the system, however, and these comprise a servic