Kinetic alterations independent of walking speed in elderly fallers

OBJECTIVES: To determine if joint kinetic gait alterations in fallers persist when they attempt to walk at a faster speed that is more comparable with nonfallers' comfortable walking speed. DESIGN: Retrospective, case-control study. Stereophotogrammetric and force platform data were collected. SETTING: A gait laboratory. PARTICIPANTS: Sixteen elderly subjects who had at least 2 falls in the last 6 months from an unclear cause and 23 elderly subjects with no history of repeated falls. MAIN OUTCOME MEASURES: Differences in all major peak joint kinetic (moment and power) values during the gait cycle between elderly nonfallers walking at comfortable speed and elderly fallers walking at (1) comfortable and (2) fast speed. RESULTS: Statistically significant differences present at both comfortable and fast walking speeds were present in 4 sagittal plane parameters. There was an increase in peak external hip flexion moment in stance, a reduction in peak hip extension moment, a reduction in knee flexion moment in preswing, and a reduction in knee power absorption in preswing. CONCLUSION: The presence and persistence of 4 specific alterations in sagittal plane joint kinetics at both comfortable and fast walking speeds imply specific intrinsic pattern differences and allow for new insights into the mechanics of gait in elderly people who fall. The presence of these alterations also suggests they may serve as potential identifiable markers to detect those who may be at risk for falls.