Synovial Joint
Definition
Synonym : diarthrosis
Where two bones join to form a structure for the purpose of mobility
The bones are held together by a fibrous capsule, with a cavity inside which is lined by a fluid secreting membrane called Synovium
Examples of Synovial Joint
Knee joint, hip joint, shoulder joint, elbow joint
Charecteristics of a synovial Joint
Bone ends are lined by cartilage - articular cartilage (hyaline)
Lubricated by a thin film of synovial fluid secreted by synovial membrane - synovial fluid : lubrication, nutrition, shock absorption
Outside the synovial membrane there is a joint capsule made of fibrous tissue
The fibrous capsule fuses with the periosteum of the bones and hold them together
Articular discs or menisci - the fibrocartilage pads between opposing surfaces in a joint
Articular fat pads - adipose tissue pads that protect the articular cartilage
Tendons - cords of dense regular connective tissue composed of parallel bundles of collagen fibers
Accessory ligaments (extracapsular and intracapsular) - prevent extreme movements that may damage the articulation
Bursae - saclike structures that are situated strategically to alleviate friction in some joints (shoulder and knee) that are filled with fluid that is similar to synovial fluid
Blood supply
Blooe supply to a synovial joint is by an anastanosis formed by the surrounding arteries
