Abstract

After resecting the lateral collateral ligament of the knee in 56 male mature rats, the authors replaced it by an autogenous transplant of the same size, made of fascia lata, ligament or patellar tendon. The authors then studied this transplant after an evolution of 2 days to 5 1/2 months. This lapse of time can be divided into three stages: an initial stage (first week), marked by transplant necrosis and acute inflammation--an early stage (from the second to the fourth week), which shows the migration of the cells from the host to the transplant and the rebuilding of collagen fibers. Tissues with a loose, extensible, but weak texture, such as the fascia lata, are totally colonized by the fibroblasts. Tissues with a dense, strong, but less extensible texture, as the patellar tendon, are soon destroyed and recolonized at the periphery, whereas their center is destroyed and recolonized by fibroblasts later and more irregularly--a late phase of consolidation (from the second to the fifth month), which shows the rebuilding of a dense collagen network and its reorientation. In fascia lata transplants, this new collagen is homogeneous and is made of parallel bundles. In tendon transplants, the network is not homogeneous. It has a persistent nodular aspect at the periphery and well-oriented bundles, separated by calcified or granulomatous foci at the center. In the case of ligament transplants, the new collagen network shows an intermediate aspect between the two described above. The weakest regular connective tissues are the best for ligamentoplasties, and tendons are the worst.