Collagen types I and III and fibronectin in healing anterior cruciate ligament after reconstruction with carbon fibre

The presence of the connective tissue components fibronectin and collagen types I and III have been demonstrated by immunohistological methods after reconstruction of the anterior cruciate ligament of pigs with carbon fibre. The carbon fibre ligament prosthesis was covered with pediculated fascia lata. During the initial 16-week period, fibronectin was seen both in the surrounding fascial layer and between the carbon fibres of the substitute. Type III collagen was also found, especially in the fascial layer, but only with mild staining intensity in the carbon fibre prosthesis. Type I collagen was absent from the carbon fibre prosthesis and was seen only in the fascial layer. Results indicate that the tissue in the ‘neoligament’ after carbon fibre reconstruction consists mostly of granulation tissue with a high amount of fibronectin, and type III collagen from mesenchymal cells without sufficient amount of type I collagen with tensile strength to withstand subsequent mobilization and rehabilitation.