Effects of a custom-made hinged knee brace with knee flexion support for patients with knee osteoarthritis:a preliminary study.

A knee brace for medial knee osteoarthritis (OA) is required to restrict knee adduction moment (KAM), but must not restrict knee flexion during swing phase. There is no report of a knee brace with both functions. The purpose of this study is to investigate the effect of the custom-made hinged knee brace for patients with knee OA compared to the hinged knee brace generally used, and to assess the KAM and knee flexion angle during swing phase. Fifteen patients (average age: 71.6 ± 7.8 years old) with medial knee OA participated. Gait analysis was performed using a 3-D motion analysis system to measure two conditions: hinged knee brace (KB), and a custom-made hinged knee brace with knee-flexion support- equipped rubber tubes at the posterior of the lateral and medial side poles (KBF). The peak KAM with KBF was significantly smaller than those with the KB (P=0.004, the difference between these conditions of KAM: 0.06 Nm/kg). The peak knee flexion angles during swing phase with KBF were also significantly larger than those with the KB (P=0.004, the difference between these conditions of knee flexion angle: 1.5 degrees). The custom-made brace with one type of tube actuator in the present study could decrease KAM and make for a small increase of knee flexion angle as opposed to the hinged knee brace.