Noriyoshi Nagamoto

Stabilometric assessment in the anterior cruciate ligament-reconstructed knee.

OBJECTIVE To examine the hypotheses that anterior cruciate ligament (ACL) reconstruction improves the proprioception of the knee beyond the level of ACL-deficient knees, and that proprioception of the knee correlates well with knee function after ACL reconstruction. PATIENTS Fifty-three patients with ACL-reconstructed knees (22 men and 31 women), 30 physically active healthy volunteers with normal knees (15 men and 15 women), and 30 patients with chronic ACL-deficient knees (15 men and 15 women). MAIN OUTCOME MEASURES A stabilometric assessment, which is considered to be a useful method for evaluating proprioception objectively, was used to compare the one-leg standing balance among three groups; and the relationship between subjective knee function, satisfaction, hop index, knee laxity, isokinetic thigh muscle strength, and one-leg standing balance in the ACL-reconstructed patients was also analyzed. RESULTS The one-leg standing balance of the patients with ACL-reconstructed knees was still impaired compared with that of healthy volunteers (men, p < 0.05; women, p < 0.01), but significantly better than that of the patients with ACL-deficient knees (men, p < 0.001; women, p < 0.001). The one-leg standing balance of the patients with ACL-reconstructed knees correlated well with their functional outcomes such as subjective knee function (men, p < 0.001; women, p < 0.01), satisfaction (men, p < 0.01; women, p < 0.001), and hop index (men, p < 0.001; women, p < 0.001), whereas poor correlation was seen between functional outcomes and mechanical stability. CONCLUSIONS The results suggest that knee function after ACL-reconstruction should be closely related with knee proprioception, and indicate that the usefulness of stabilometric assessment in the evaluation of the function of ACL-reconstructed knees.