A joint is defined as the point at which two or more bones articulate. Joints can be easily classified by the type of tissue present. Using this method, we can split the joints of the body into fibrous, cartilaginous and synovial joints.
Fibrous joints can be further subclassified into sutures, gomphoses and syndesmoses.
Sutures are immovable joints (called a synarthrosis), only found between the flat, plate-like bones of the skull.
Gomphoses are also immovable joints and can be found where the teeth articulate with their sockets, with periodontal ligaments.
Syndesmoses are slightly movable joints (called an amphiarthrosis) comprised of bones held together by an interosseous membrane. Eg: The middle radio-ulnar and middle tibiofibular joint
Cartilaginous joints have bones attached with fibrocartilage or hyaline cartilage.
Synchondroses or primary cartilaginous joints involve only hyaline cartilage. The joints can be immovable (synarthroses) or slightly movable (amphiarthroses). Eg: The joint between the diaphysis and epiphysis of a growing long bone
Symphyses or secondary cartilaginous joint can involve fibrocartilage or hyaline cartilage and are slightly movable (amphiarthroses), an example of a which is the pubic symphysis.
A synovial joint is a joint filled with synovial fluid which tends to be fully moveable (diarthroses), and are the main type of joint found in the body. They allow a huge range of movements are classified by their movement.
|Hinge||Permits flexion and extension. Elbow joint is a notable example.|
|Pivot||Allows rotation; a, round bony process fits into a bony ligamentous socket. Examples include the atlantoaxial joint & proximal radio-ulnar joint (top of the neck and elbow)|
|Ball & Socket||Permits movement in several axes; a rounded head fits into a concavity. An example is the glenohumeral joint (shoulder).|
|Saddle||Concave and convex joint surfaces unite at saddle joints, e.g. Metatarsophalangeal joint (toes)|
|Plane||Permit gliding or sliding movements, e.g. Acromioclavicular joint (collarbone to shoulder blade)|
|Condyloid||Permits flexion, extension, adduction, abduction and circumduction e.g. Metacarpophalangeal joint (in the middle of your hand).|