Reconstruction of the anterior cruciate ligament. Long-term effects of different knee angles at primary immobilization and different modes of early training.

The clinical results in 29 patients who had undergone ACL reconstruction with quadriceps-patellar tendon graft over-the-top were studied at an average of 28 months postoperatively. Postoperative immobilization was at either 30 degrees (N = 17) or 70 degrees (N = 12) of knee flexion for 6 weeks. All patients then followed a common preparatory training program for 8 weeks. In the 14th postoperative week the patients were put on either progressive resistance training (N = 12) or isokinetic training (N = 17) for 6 weeks, after which all had identical training. Independent of primary knee immobilization angle or training regimens, no differences could be demonstrated with respect to stability, range of motion, function, or isokinetic mechanical output. For all patients, Lysholm knee function score improved from 60.5 to 93.6 (P less than 0.001) and activity level from 3.9 to 6.3 (P less than 0.001). Isokinetic peak torque, contractional work, and mean power of the quadriceps at 30, 90, and 180 deg/sec were lower in the injured compared to the noninjured leg (78% to 90%; P less than 0.01) both preoperatively and at followup, and there were no significant differences between the preoperative and follow-up values. Clinical stability improved (P less than 0.001) in 19 of the 29 patients (66%) and in 11 of those 17 patients with early isokinetic training (65%). Performance tests were normal in 23 of 29 patients (79%), with minor abnormalities in the rest.