Moderate-heeled shoes and knee joint torques relevant to the development and progression of knee osteoarthritis

Objective: To determine if women's dress shoes with heels of just 1.5in (3.8cm) in height increases knee joint torques, which are thought to be relevant to the development and/or progression of knee osteoarthritis (OA) in both the medial and patellofemoral compartments. Design: Randomized controlled trial. Setting: A 3-dimensional motion analysis gait laboratory. Participants: Twenty-nine healthy young women (age, 26.7 +/- 5.0y) and 20 healthy elderly adult women (age, 75.3 +/- 6.5y). Interventions: Not applicable. Main Outcome Measures: Peak external varus knee torque in early and late stance and prolongation of flexor knee torque in early stance. Three-dimensional data on lower-extremity torques and motion were collected during walking while (1) wearing shoes with 1.5-in high heels and (2) wearing control shoes without any additional heel. Data were plotted and qualitatively compared; major peak values and timing were statistically compared between the 2 conditions using paired t tests. Results: Peak knee varus torque during late stance was statistically significantly greater with the heeled shoes than with the controls, with increases of 14% in the young women and 9% in the elderly women. With the heeled shoes, the early stance phase knee flexor torque was significantly prolonged, by 19% in the young women and by 14% in elderly women. Also, the peak flexor torque was 7% higher with the heeled shoe in the elderly women. Conclusions: Even shoes with moderately high heels (1.5in) significantly increase knee torques thought to be relevant in the development and/or progression of knee OA. Women, particularly those who already have knee OA, should be advised against wearing these types of shoes.