| The meniscus provides protection to the articular cartilage of the knee by transmitting loads through the joint, distributing high peak stresses on the underlying surfaces, providing shock absorption, and aiding in joint lubrication. It is well accepted that significant loss of meniscal tissue leads to degenerative changes in the joint. Treatment alternatives for patients suffering from severe meniscal deficiency are limited, and thus far have not been shown to offer long-term protection to the underlying cartilage.;This dissertation describes the development of a tissue engineered meniscus scaffold comprised of a chemically crosslinked type I collagen sponge reinforced with resorbable polymer fibers. The long-term goal of this work is to develop a resorbable scaffold which promotes the growth of fibrocartilaginous-like tissue while preventing or delaying degenerative changes in the underlying articular surfaces.;Preliminary evaluation was completed on several potential designs varying in fiber orientation, collagen sponge density, and overall geometry. Two were chosen to evaluate a series of hypotheses related to their biomechanical properties, in vitro biocompatibility, and in vivo biocompatibility. Both designs were found to possess the structural properties necessary to function as a load-bearing device in the knee. Furthermore, they were fabricated from resorbable materials which supported the proliferation of fibrochondrocytes in vitro. A non-functional evaluation in a rabbit model demonstrated the scaffold to elicit a biological response appropriate for a resorbable device. From the results of these experiments, one design was chosen for functional evaluation in a large animal model.;Scaffolds were implanted at the site of a total meniscectomy in a sheep knee. Short-term results demonstrated that scaffolds incorporated into the joint and elicited an appropriate biological response. However, observed neo-tissue did not possess the high organization inherent to fibrocartilaginous tissues. Furthermore, scaffolds were found to have a limited protective effect on the articular cartilage as variable levels of degenerative changes were observed for all subjects. Results from this evaluation showed proof of principle for this type of scaffold for the treatment of significant meniscal deficiency. However, further optimization of the device is required before it can proceed to clinical evaluation. |
