Functional assessment of knee joint position sense following anterior cruciate ligament reconstruction

Context: The anterior cruciate ligament (ACL) has both mechanical and proprioceptive (sensory) functions. Knee-joint proprioception has been assessed using either reproduction of position or threshold to detect passive motion in non-weight-bearing positions. It has been suggested that a more functional and dynamic/active assessment of proprioception might clarify the effects of injury and reconstruction on the proprioceptive function of ACL at the knee joint. Objective: To assess knee joint position sense (JPS) following ACL reconstruction in functional positions. Subjects: Twelve male patients who had undergone ACL reconstruction and 12 male healthy control subjects participated in the study. Methods and main outcome measures: JPS was evaluated by reproduction of the angles in weight-bearing position with limb movement into flexion and extension. The dominant knee of healthy subjects and both (reconstructed and uninjured) knees of the patients were tested. Absolute angular error was used as a dependent variable. Results: There was no significant difference between the operated and uninjured knees of patients or between patients and healthy controls (p >= 0.05). These results were measured during two tasks of limb movement into flexion and extension. Conclusion: We found no evidence of impaired JPS in weight-bearing positions in subjects with ACL reconstruction at a mean follow-up of 11 months after surgery compared with subjects with healthy knees.