What is the structure of a synovial joint?

What is the structure and function of a normal synovial joint?

• Answer:

  Synovial joints have a special structure that distinguishes them from other types of joint. The presence of a space called a synovial cavity between aticulating bones allows the joint to be movable. The bones at a synovial joint are covered by a membrane of hyaline cartilage. This cartilage, also known as articular cartilage serves a function as shock-absorber and also, along with the secretion of synovial fluid in the membrane, helps reduce friction. A sleeve-like articular capsule encloses the cavity and unites articulating bones. The articular capsule is composed of 2 layers - 1) an outer membrane of dense irregular connective tissue called a fibrous capsule, and 2) the synovial membrane which is composed of areolar tissue with elastic fibers. Along with connective ligaments, the membranes work cohesively with the articular fat pads, composed of adipose connective tissue to help pad the whole mechanism. Synovial joints are classified functionally as diarthrosis, which as its name would imply are movable in both directions...completely movable in other words. They have a variety of different shpes such as the ball and socket, and permit several different types of movements.