Relationship of knee joint proprioception to pain and disability in individuals with knee osteoarthritis.

Proprioception plays an integral role in neuromotor control of the knee joint and deficits in knee joint proprioception are well documented in individuals with knee osteoarthritis (OA). However, the functional relevance of these deficits is not clear. This cross-sectional study evaluated the relationship between knee joint proprioception and pain and disability in a large cohort of individuals with knee OA. Two hundred and twenty participants (145 F, 75 M) with symptomatic knee OA were recruited from the community. Five non-weight bearing active tests with ipsilateral limb matching responses were performed at 20 degrees and 40 degrees flexion to measure knee joint position sense. Pain and disability were assessed by self-reported questionnaires and objective measures of balance and gait. Results showed little association between knee joint position sense variables and measures of pain and disability (r values <0.24, most p>0.05). When comparing participants with the worst and best joint position sense, no significant differences in pain and disability could be found (p>0.05). While our study design does not allow causality to be established, these results suggest that deficits in joint position sense may be due to factors other than pain and that deficits are not large enough to impact upon disability.