Experimental validation on finite element stress analysis of a polymeric orthotic device

A summary of instrumentation procedure and preliminary results obtained from the experimental strain measurement for validation on earlier finite element stress analysis of a polypropylene ankle-foot orthosis (AFO) is presented. AFO is an assistive device prescribed to patients who develop pathological gait after sustaining a stroke. The strain gage was bonded to the surface of the AFO. The strain information obtained in the AFO during gait activities are the principal strain and allow determination of the maximum stress. The activities include slow walk, fast walk, and jump. The result confirmed that the location where the maximum peak stress occurred in the AFO during gait is in the middle-lower lateral neck region. This was further confirmed by clinical observations that the AFO fails constantly in the neck region