Wrist joint moments of walker-assisted gait: A study of biomechanics and instrumentation

Abstract

While walkers are commonly prescribed to improve patient stability and ambulatory ability, quantitative study of the biomechanical and functional requirements for effective walker use is limited. To investigate the changes in wrist joint moments that occur with the use of a standard walker, a strain gauge-based walker instrumentation system was developed for the measurement of wrist joint moments. This walker dynamometer was integrated with an upper extremity biomechanical model. Preliminary system data were collected for twelve healthy, right-handed young adults following informed consent. Bilateral upper extremity kinematic data were acquired with a six-camera motion analysis system. Internal joint moments at the wrist were determined in the three clinical planes using the inverse dynamics method. Results showed that during a walker-assisted gait there were several typical demands of wrist abductor, adductor, flexor and external rotator. An interesting 'bare phase' of wrist joint moments was also found in phase angle [-30°, 30°] of gait cycle. Complete description of wrist joint moments during walker-assisted gait may provide insight into walker use parameters and rehabilitative strategies.