joints

Fixed (Fibrous joints)•No movement occurs between the bones involved.•Held in place by fibrous connective tissue•On impact bone fracture rather that joint damage.

Slightly movable (cartilaginous joints)•Allows very limited movement•Held in place by fibrous cartilage•eg symphysis pubis, vertebrae joints, joints between ribs and sternum

Freely movable (synovial joints)•Amount of movement is limited only by ligaments, muscles, tendons and adjoining bones.•Highly mobile but equally weak

Ball-and-socket jointsSpherical head of one bone fits into cup-like head of another•Only occur in two places: Shoulder & Hip

Hinge JointAllows movement in one plane only.•Convex surface of one bone fits into concave surface of another

• E.g. elbow (ulna/Humerus), wrist (radius/carpals) & knee (ankle, fingers & toes)

Pivot Joint•Rounded, pointed or conical end of one bone articulates with a ring (part bone, part ligament)•E.g. 1st vertebrae (head) / 2nd vertebrae & radius / ulna

Gliding JointGliding movement in any direction (back/forth, side/side), limited only by ligaments or bony processes.•E.g. carpals, tarsals, sternum / clavicle, sternum / clavicle

Saddle jointTwo saddle shaped joints•Allows side/side and back/forth movements•e.g. thumb / hand

Condyloid (ellipsoid) jointSlightly convex fits with slightly concave•Allows side/side or back/forth movements•e.g. radius/carpal, metacarpal/phalanges

Movement of a Joint:

•Flexion: (bending) decreases angle between articulating bones•Extension: (Straightening) increases angle between articulating bones•Abduction: movement away from the body•Adduction: movement towards from the body•Rotation: Movement of a bone around its long axis.