Fibrocartilage

Fibrocartilage is intermediate in character between hyaline cartilage and dense connective tissue.

1. Composition and organization. Fibrocartilage is characterized by abundant type I collagen fibers; at low magnification, it closely resembles dense connective tissue. The ground sub stance contains equal amounts of dermatan sulfate and chondroitin sulfate. The matrix immediately surrounding the chondrocytes resembles that of hyaline cartilage and contains some type II collagen. The chondrocytes are distributed in columnar isogenous groups between the densely packed type I collagen bundles. There is no distinguishable perichondrium.


2. Histogenesis and growth. At sites where strong mechanical stresses occur, fibrocartilage develops from dense regular connective tissue through the transformation of fibroblasts or fibroblast like precursors into chondrocytes. Fibrocartilage growth has not been closely examined.

3. Function and location. Fibrocartilage is always associated with dense connective tissue, and the border between the two is usually indistinct. Its combination of cartilaginous ground substance and dense collagen bundles allows fibrocartilage to resist deformation under great stress; it is important in attaching bone to bone and providing restricted mobility. Sites in humans include the annulus fibrosus of the intervertebral disks, the symphysis pubis, and certain bone-ligament junctions.