Abstract
Joints are generally divided into two or three classes, (14, 28). 1- Synarthroses, which are relatively immovable, and characterized by a continuous union of bones separated by connective tissue or hyaline cartilage. There are four varieties of synarthroses; schindylesis, gomphosis, suture, and synchondrosis. 2- Amphiarthroses, include those articulations in which the bony surfaces are separated by fibrocartilage or united by interosseous ligaments. They permit slight movement. 3- Diarthroses, are freely movable joints, having a number of characteristics which distinguish them from the synarthroses and amphiarthroses. The contiguous bony structures have articular surfaces which are covered by articular cartilage of the hyaline typ. The joint is enclosed in a capsule, which has an inner synovial layer and an outer fibrous covering, and contains synovial fluid. There are ligaments connecting the bones. There are six forms of diarthrosis; ginglymus, trochoid, condyloid, saddle, arthrodia, and enarthrosis.