Stairclimbing kinematics on stairs of differing dimensions.

The purpose of this study was to provide a kinematic description of the task of stair ascent and descent. Fifteen women were divided into short, medium, and tall subject groups. Three testing staircases of different riser and tread dimensions were used. Temporal and cinematographic data were collected simultaneously via switchmats and a high-speed camera, respectively. Measures of stairclimbing gait cycle duration, swing and stance phase durations, cadence, and velocity appeared to be systematically related to subject height. Stance (19% to 64%) and swing (36% to 81%) phase durations varied considerably depending on stair dimensions during stair descent. Less variation was observed in stance (50% to 60%) and swing (40% to 50%) values during tasks of stair ascent. Individuals appeared to adjust to stair dimensions by varying the flexion/extension patterns of the knee rather than those of the ankle or hip. Depending on the staircase climbed, knee flexion angles ranging from 83 degrees to 105 degrees were required. Stair dimensions, therefore, appeared to influence the temporal and angular kinematics of the lower limb during stairclimbing.