The Effect of Knee Braces on Tibial Rotation in Anterior Cruciate Ligament–Deficient Knees During High-Demand Athletic Activities

Abstract

To examine if bracing can restrict tibial rotation in anterior cruciate ligament (ACL)-deficient patients during high loading activities. Repeated measures. Kinematic data were collected with an 8-camera Vicon system while each patient performed 2 tasks that are known to cause increased rotational and translational loads on the knee: (1) descending from a stair and subsequent pivoting, and (2) landing from a platform and subsequent pivoting. The tasks were repeated under 3 brace conditions for the ACL-deficient knee: (1) wearing a prophylactic brace (braced condition), (2) wearing a patellofemoral brace (sleeved condition), and (3) without brace (unbraced condition). Biomechanical laboratory study. Twenty-one male subjects with a confirmed unilateral ACL rupture were assessed in vivo. Tibial internal rotation. Two repeated measures ANOVAs tested for differences in tibial internal rotation among the 3 conditions of the ACL-deficient knee and the unbraced condition of the intact knee. In both tasks, tibial rotation was significantly lower in the intact knee compared with all 3 conditions of the ACL-deficient knee (P ≤ 0.031). Bracing the ACL-deficient knee resulted in lower rotation than the unbraced (P ≤ 0.001) and sleeved (P ≤ 0.033) conditions. The sleeved condition resulted in lower tibial rotation in the drop landing and pivoting task compared with the unbraced condition (P = 0.019) but not in the stair descending and pivoting task (P = 0.256). Bracing decreased the excessive tibial rotation in ACL-deficient patients during high-demand activities but failed to fully restore normative values. If knee braces can enhance rotational knee stability in ACL-deficient patients, then they could possibly play an important role in preventing further knee pathology in such patients.