Knee joint torques: a comparison between women and men during barefoot walking.
OBJECTIVE: To determine if knee joint torques, which are likely relevant to the development and, possibly, progression of knee osteoarthritis, are equivalent between genders during natural, barefoot walking. DESIGN: Collected stereophotogrammetric and force platform data during comfortable, barefoot walking. Knee joint torques were plotted and statistically compared between genders using both an unpaired t test (p < .05) and an equivalence test (20% delta). SETTING: A gait laboratory. PARTICIPANTS: One hundred ten healthy, nondisabled young women and men. MAIN OUTCOME MEASURES: Four knee joint torque parameters normalized for height and weight: (1) peak and (2) duration of sagittal flexor joint torque from early to midstance, and (3) first and (4) second peak coronal (frontal) varus torque values during the stance period. RESULTS: No statistically significant differences between genders were found, and the values were equivalent between genders for each of the 4 knee joint torque parameters. CONCLUSION: These findings support the hypothesis that under similar barefoot conditions women and men have a similar intrinsic biomechanic risk for knee osteoarthritis. Future research to assess the effects of other potential biomechanic factors, such as shoe-wear and activity type, may assist not only in preventing knee joint osteoarthritis, but also in developing new rehabilitative strategies to treat osteoarthritis of the knee.