Effects of arch support insoles on gait patterns of patients with knee osteoarthritis

Although arch support orthotics are prescribed for knee osteoarthritis (OA) patients in clinics, the biomechanical effects of such devices are not fully clear. This study conducts an experimental investigation to evaluate the short-term effects of shoes with arch support insoles on the gait patterns of patients with knee OA during level walking. Twelve adults with knee OA were recruited, and biomechanical data were measured under three test conditions: walking barefoot, walking in shoes, and walking in shoes and insoles. Participants' gait patterns were recorded and analyzed using a motion analysis system, Kistler force plates, and EVaRT software.Walking in shoeswith insoles significantly increased the peak knee flexion angle and the peak dorsiflexion and external rotation angles of the ankle, but reduced the peak ankle internal rotation angle compared to those for walking barefoot. Both walking in shoes with insoles and walking in shoes significantly reduced the toe-out angle compared to that for walking barefoot. However, no significant difference was observed in the peak knee varus moment. The results suggest that the foot insoles and shoes tested in this study might have influenced the ankle joint in OA patients. In view of the significantly decreased toe-out angle of the foot and increasing trend in the knee varus moment, the use of shoes with insoles may be unsuitable for knee OA patients.