The intra-articular effect of various postoperative managements following knee ligament repair: an experimental study in dogs.

The intra-articular changes in dog knees were studied following repair of the anterior cruciate and medial collateral ligaments under various postoperative managements: early mobilization, immobilization for 6 weeks in a plaster cast, and limited mobilization for 4 weeks in a cast-brace. The animals were sacrificed at 12 weeks after operation and osteoarthritic changes were graded according to the system described by Mankin et al. The osteoarthritic changes of the knee joints in the mobilized group were significantly less than those in the immobilized and in the cast-brace groups. Medial collateral ligaments were found well healed in most animals; however, anterior cruciate ligaments showed poor healing in the animals treated with early unlimited motion. Postoperative immobilization for more than 6 weeks causes considerable damage to the articular cartilage while early unlimited motion appears to compromise healing of the anterior cruciate ligaments.