The injured anterior cruciate ligament and neuromuscular rehabilitation

Abstract: Two prospective, short-term and long-term consecutive randomized studies on non-surgical treated patients with an ACL injury were performed. None of the patients were athletes on a professional level. Outcome measures : isometric muscle strength and isokinetic musclefunction, one-leg hop test, single limb balance, Lysholm knee score and Tegner activity level. In study number one 26 patients with non-acute ACL injuries, with a late diagnosis of symptomatic anterior cruciate ligament lesion, were examined and randomized to open-chain or closed-chain training for a 3 month period. Short term effect after training: Knee extensors improved significantly in both groups, with significantly higher value in isometric extension in open-chain training group,the remaining values with minor differences only. At 3 months standing balance was normalized on the uninjured, but not on the injured side, despite restoration of thigh muscle strength. At 12 months, standing balance was normalized in both legs and persisted at 36 month follow-up. Lysholm knee-score increased significantly during initial 3 months. After 36 months the score was excellent (>83) in 21 out of the 22 remaining patients. Isometric muscle strength values persisted at 36 months. Recreational sports were resumed after training by most patients. 100 patients with acute ACL injury revealed associate lesions in 82% of the cases. Need of supervision in training or not was evaluated, the patients were randomized to supervised or self-monitored training. A transferral of 50% of the SM patients to SV was indicated after 6 weeks, the majority were women. At 36 months isometric muscle strengths and isokinetic work capacity were significantly higher in male patients of original SV group, than in men remaining in the SM group.In transferred male patients recovery was seen with delay in time. In females no differences were observed between groups. Further studies on muscle function after ACL injuries in female patients are required. 85 patients completed the follow-up after 36 months. As part of a joint-protection strategy, restriction of hyperextension was preserved in the majority of cases during the period of follow-up and giving-way events occurred in 5-10% only of the patients during the follow-up.