To identify the sensory deficit of partial weight-bearing joint repositioning sense in subjects with unilateral osteoarthritis (OA) of the knee. The methodology was developed to incorporate measures made easily in a clinical setting. In OA, local degenerative changes can affect the function of sensory receptors and mechanoreceptors. As a result, appreciation of limb position as well as function may be compromised. Because proprioceptive sense plays an important role in reflex muscle contraction and stabilization of the joint, functional stability and joint integrity may be at risk if proprioception is impaired.
Twenty subjects with unilateral OA of the knee were age-matched with 20 controls for the purpose of this study. The difference in degrees between a target angle of knee flexion and a reposition angle was measured during a partial weight-bearing test. A Dualer (electronic dual inclinometer) was used to measure the joint reposition sense (JRS) of the knee. Both sides were tested with six repetitions on each side. A mixed-model ANOVA was applied to the data for analysis.
Comparison of the JRS between groups revealed a significant difference, with OA subjects having higher JRS error (JRSE) (p <0.001) than controls. There was no significant difference in JRSE for either side, regardless of group.
Subjects with unilateral OA of the knee demonstrated poorer performance on both legs in a partial weight-bearing reposition test than did control subjects.