Knee bracing for medial compartment osteoarthritis: effects on proprioception and postural control

Objective. To evaluate the effects of a functional knee brace specifically designed for patients with varus gonarthrosis on measures of proprioception and postural control. Subjects. Fourteen men and six women (aged 59 +/- 9 yr) with measurable var us alignment and osteoarthritis of the knee medial compartment. Methods. Proprioception was assessed in the sitting position using an isoki netic dynamometer and was quantified as the ability to replicate target kne e-joint angles. Postural control was assessed with a Force platform using t ests of single-limb standing balance performed, while the patient was stand ing on a stable surface and standing on foam, and was quantified as the tot al length of the path of the centre of pressure. All tests were performed w ith and without the patient's own custom-fit valgus brace. Results. Proprioception was significantly improved following application of the brace [mean difference - 0.7 degrees, 95% confidence interval (CT) = 0 .2 to 1.1 degrees). Postural control was not significantly affected by the use of the brace during the stable surface test (mean difference = 2.6 cm, 95% CI = - 4.3 to 9.5 cm) or the foam surface test (mean difference = 0.9 c m, 95% CI = - 7.5 to 9.4 cm). Conclusion. Although enhanced proprioception may be partially responsible f or reported improvements with the use of a brace, the present findings call into question the functional importance of the small changes observed.