Effect of Having A-Priori Knowledge of the Floor's Contaminant Condition on the Biomechanics of Slips

Abstract

Injuries and deaths are often the result of slips/falls. The perceived danger of slipping affects gait biomechanics. This paper investigated the effect of having a-priori knowledge of the floor's contaminant condition on the biomechanics of slips. Five healthy young male subjects donned a safety harness and walked across a walkway, while ground reaction forces and whole body motion were recorded bilaterally at 60 Hz. Slips on soapy floors occurred under 3 “knowledge” conditions: (1) unexpected slips, (2) slips when uncertain of the contaminant condition, and (3) slips when walking onto known contaminated floors. in (2) and (3), i.e. anticipation of slippery surfaces, subjects generated proactive reactions (reduced stance duration and foot angle at heel contact as well as greater hip flexion) compared to unexpected conditions in (1). Those reactions reduced slip potential but also minimized gait disturbances (reduced slip distance and sliding velocity of the heel) when a slip occurred.