On superficial examination this type of cartilage (also called white fibrocartilage) looks very much like dense fibrous tissue (Plate 6.3). However, in sections it is seen to be cartilage because it contains typical cartilage cells surrounded by capsules. The matrix is pervaded by numerous collagen bundles amongst which there are some fibroblasts. The fibres merge with those of surrounding connective tissue.

There is no perichondrium over the cartilage. This kind of cartilage has great tensile strength combined with considerable elasticity. The collagen in fibrocartilage is different from that in hyaline cartilage in that it is type I collagen (identical to that in connective tissue), and not type II. The fibrocartilage in contrast to hyaline cartilage does not undergo calcification.

Distribution of Fibrocartilage

- Fibrocartilage is most conspicuous in secondary cartilaginous joints or symphyses. These include the joints between bodies of vertebrae (where the cartilage forms intervertebral discs); the pubic symphysis; and the manubriosternal joint.

- In some synovial joints the joint cavity is partially or completely subdivided by an articular disc. These discs are made up of fibrocartilage (Examples are discs of the temporo- mandibular and sternoclavicular joints, and menisci of the knee joint).

- The glenoidal labrum of the shoulder joint and the acetabular labrum of the hip joint are made of fibrocartilage.

- In some situations where tendons run in deep grooves on bone, the grooves are lined by fibrocartilage. Fibrocartilage is often present where tendons are inserted into bone.