Vertical impact increase in middle age may explain idiopathic weight-bearing joint osteoarthritis

Abstract

Objective: To test the hypothesis that ground reaction force increases when a standard stepping task is performed in late middle age. Design: Consecutive sample. Setting: Internal medicine practice. Participants: Thirty-six male patients (age range, 17-72yr) from an internal medicine practice. Intervention: Subjects performed 20 consecutive footfall impacts onto a force platform while barefoot and while wearing shoes. Main Outcome Measures: Ground reaction forces were recorded for each footfall. Results: Impact is positively related to age both when barefoot (r =.84, p