Implementation and Evaluation of a Vibrotactile Assisted Monitoring and Correction System for Partial Weight-Bearing in Lower Extremities

Accurate partial weight bearing in the foot during rehabilitation from musculoskeletal injuries in lower extremities is important to ensure successful recovery. However, it is difficult for patients to know how much to load, and many are therefore reluctant to load at all. This study presents a novel footwear concept with strain gauge based force sensors and vibrotactile feedback that enables accurate foot loading and partial weight bearing monitoring during rehabilitation from musculoskeletal injuries in the lower extremities. Four force sensors integrated in the foot-sole of a sandal measures ground reaction force, and two eccentric rotating mass motors provide vibrotactile feedback to the user when a predetermined force threshold is reached. Partial weight bearing data from the force sensors are transferred wireless using wifi communication to a remote patient monitoring dashboard, enabling decision support for health personnel. We demonstrate the use of the prototype to reduce overloading in partial weight bearing in a validation experiment (N=16). Findings showed that the prototype significantly reduced overloading in the right foot for healthy adults (p < 0.05), which indicate that closed-loop force sensing footwear with vibrotactile feedback can be useful in aiding patients with musculoskeletal injuries in the lower extremities during rehabilitation.