Abstract des Autors

Objective: Prior studies have examined the effect of cadence on ground reaction forces by use of a force plate. Force plate studies generally analyze isolated steps and do not provide insight into ongoing step-to-step variations or in-shoe plantar pressures. The objective of this study was to evaluate the effect of walking cadences on in-shoe plantar pressures over extended periods of continuous walking. Design: Nonrandomized control trial. Setting: Laboratory. Patients or Other Participants: Volunteer sample of 8 able-bodied subjects. Interventions: In-shoe plantar pressures were studied during four minutes of continuous walking at controlled cadences of 70, 80, 90, 100, 110, and 120 steps/min. For each cadence more than 200 steps were analyzed for each of the 8 subjects. Main Outcome Measures: Pressure-time integrals, foot-to-floor contact durations, and peak pressures at all 14 locations were processed for each step. Changes were calculated compared to values at 70 steps/min. Results: With increasing cadence, mean pressure-time integrals continuously decreased (45% at 120 steps/min); mean foot-to-floor contact durations continuously decreased (64% at 120 steps/min); and mean peak pressures increased (119% at 120 steps/min). Conclusions: Our results show that as walking cadence increases, pressure-time integrals and foot-to-floor contact durations decrease, and peak plantar pressures increase. This is clinically relevant to all kinetic gait studies because our results suggest that normal values should be established for each cadence. Verf.-Referat