Types of joints (structure+function)
Fibrous joints
-Connected by fibrous tissue - There are 3 types: sutural, syndesmosis, and gamphosis
Synovial Joints
-bones are held together by a complex joint cavity; -most mobile types of joints •There articular surfaces are covered with hyaline cartilage. This articular cartilage is avascular, non nervous and elastic. Lubricated with synovial fluid, the cartilage forms slippery surfaces for free movements. •Between the articular surfaces there is a joint cavity filled with synovial fluid. The cavity may be partially or completely subdivided by an articular disc known as meniscus. •The joint is surrounded by an articular capsule which is fibrous in nature and is lined by synovial membrane. Because of its rich nerve supply the fibrous capsule is sensitive to stretches imposed by movements. •The synovial membrane lines the entire joint except the articular surfaces covered by hyaline cartilage. It is this membrane that secretes the slimy fluid called synovial fluid which lubricates the joint and nourishes the articular cartilage. •Varying degrees of movements are always permitted by the synovial joints. Types: ball and socket joint, ellipsoid joint, saddle joint, hinge joint, pivot joint ALL synovial joints are diarthrosis
CJ: Symphsis:
-bones held together by a plate of fibrocartilage ex: discs between vertebrae bodies -fibrocartilage discs at the symphis joint SYNARTHROSIS: this joint, no true movement
Cartilaginous joints
Bones are connected by cartilage. There is no joint cavity.
FJ: Gomphosis
Gamphosis: held together by "peg and socket." (the short connective tissue fibers) AMPHIARTHROSIS
FJ: Sutural joints:
Sutural: connected by short connective tissue fibers, an example is an adult skull SYNARTHROSIS. (no movement)
FJ: Syndesmosis
Syndesmosis: held together by lingamous tissue ex: fibia/tibia (interosseous membrane) AMPHIARTHROSIS. (little movement)
CJ: Synchondrosis:
when connecting medium is hyaline cartilage Sometimes, this is a temporary form of joint called epiphyseal growth plate, where the cartilage is converted into bone before adult life. synchondrosis -> synostosis joint once its matures (endochondral ossification) EX: coastal cartilage from #1 rib to sternum SYNARTHROSIS