The Importance of Understanding Foot Posture Strategies during Stair Descent for Forensic Incident Investigations

Falls on stairs are commonly claimed to be caused by slipping on the tread nosing, but few studies have explored specific foot kinematics at initial contact during stair descent. Further understanding of such kinematics can aid forensic incident investigations. We investigated foot posture at initial contact with the tread surface of seven participants while descending stairs to determine: a) foot posture variability across participants, and b) the effects of foot posture with respect to the nosing on foot placement. We calculated foot posture as the angle at initial contact relative to the horizontal plane using two consistent landmark points on the subjects’ shoes. Our preliminary results demonstrated inter-subject and intra-subject significant differences in foot posture (P<0.05) for both legs. These results demonstrate that further exploring this at specific instances of the gait cycle during stair descent is crucial to better understand fall events during forensic investigations.