Meniscal substitution with a Teflon-periosteal composite graft: a rabbit experiment

A Teflon-periosteal composite graft was used as a substitute for the medical rabbit meniscus and was followed for a 3 month period. The results were compared to joints with autotransplantation of the medial meniscus and to non-operated control knees. Joint in vitro mechanics were similar to the non-operated controls for both treatments. Macroscopically, all composite menisci had changed in shape and the graft was found as a small remnant at the capsular periphery with prolonged or detached attachments resulting in an insufficient coverage of the tibial plateau. Except for one case, the autografts had healed in, but showed, similar to the composite menisci, prolongation of the attachments and insufficient coverage of the tibial plateau. The femoral and tibial cartilage showed osteoarthritic changes after both treatments. Except for one specimen, the artificial material was covered and penetrated by fibrocytes, and was fixed to the capsule without gap formation; however, fibrochondrocytes were not seen. The biological coat was thin and Teflon particles extruded from the matrix in some specimens, which was reflected by synovitis with foreign body reaction. Knees with autografts had a similar low-grade synovitis without any foreign body reaction. The importance of the attachment sites as well as the normal material properties of the substitute is pointed out.