Effects of knee bracing on postural control after anterior cruciate ligament rupture

Study design: Randomized clinical trial. Objectives: To investigate the effects of functional knee braces on postural control in patients with anterior cruciate ligament (ACL) rupture. Background: ACL rupture leads to both mechanical knee instability and deficits in proprioception. Although elastic knee braces do not increase mechanical stability, patients report improved stability when wearing a brace. Elastic braces were found to reduce the loss of proprioception. It is, however, still unclear whether they also improve postural control, which involves the processing of proprioceptive input at a higher level. Methods: We studied 58 patients with isolated unilateral ACL rupture using computerized dynamic posturography and compared overall stability index (OSI) scores for injured and uninjured legs with and without a knee brace. In addition, patients were classified as copers and non-copers depending on knee function. Results: Within subjects, OSI scores were 3.0 +/- 1.10 degrees for uninjured legs when unbraced, 2.8 +/- 1.3 degrees for uninjured legs when braced (p = 0.17), 3.7 +/- 1.5 degrees for unbraced injured legs, and 2.9 +/- 1.3 degrees for braced injured legs ( p < 0.001). For the injured legs of copers and non-copers, OSI scores were 3.4 degrees +/- 1.2 degrees for copers and 4.0 degrees +/- 1.6 degrees for non-copers in the unbraced condition (p = 0.11) and 2.7 +/- 1.0 degrees for copers and 3.1 +/- 1.40 degrees for non-copers in the braced condition (p = 0.26). Conclusion: Elastic knee braces increase postural stability by approximately 22% in patients with ACL rupture. There was no difference in postural stability between uninjured and injured legs in the braced condition. One possible explanation is that bracing improves both proprioception and postural control. Level of evidence: Controlled clinical trial, level 2a. (C) 2011 Elsevier B.V. All rights reserved.