The response of the lower extremity to impact forces. II. Computerized mechanical impedance measurements.

The preferred method for the noninvasive assessment of the mechanical properties of the musculoskeletal system is the measurement of mechanical impedance by means of an instrumented impact hammer and accelerometer. When coupled to an interactive computer system, this is shown to be a powerful tool in the quantitation of mechanical parameters associated with various orthopaedic conditions. The technique of measurement and the interpretation of results is discussed with reference to a model based on elastic rebound.