The knee joint meniscus. A fibrocartilage of some distinction.

It is now well established that the meniscus performs a number of roles that are important to the efficient performance of the knee joint. Of particular importance is the recognition of its load-bearing function and its stabilization of the joint during flexion-extension. The compression of the wedge-shaped meniscus during loading is translated into circumferential stresses, and the collagen fiber distribution and orientation is well adapted for this mechanical role. Proteoglycans of the meniscus have structural characteristics in common with those of articular cartilage but do not appear to influence the tensile properties of menisci. With aging and degeneration, compositional changes take place within the meniscus that reduce its ability to transmit tensional stresses, and this contributes to failure. Total meniscectomy is not a benign procedure. Partial excision has less deleterious effects on the joint. Surgical repair of meniscus lesions has now emerged as a procedure of some significance and laboratory research suggests that a solution to this problem may be within reach. Experimental studies in dogs also indicate that chondroprotective agents such as semisynthetic sulfated polysaccharides may protect articular cartilage after meniscectomy.