Important Human Body joints
The place of articulation between two or more bones is called a joint.
Joints are of three types — fibrous (immovable; sutures between the bones of skull), cartilaginous (slightly movable; between adjacent vertebrae) and synovial (movable; filled with synovial fluid).
According to their shapes and the movements they allow, the synovial joints are of six types.
A gliding joint permits only back-and-forth and side-to-side movements e.g., joints found between the carpal bones and tarsal bones.
A hinge joint allows movement primarily in one plane. e.g., elbow, knee, ankle and interphalangeal joints.
A pivot joint also allows movement in only one plane. e.g., joints between the atlas and axis.
A condyloid or ellipsoid joint allows movement in two planes, back and forth and side-to-side. e.g., joints between the metacarpals and phalanges.
A saddle joint allows the same movements as an ellipsoid joint, but the movements are free. e.g., joint between the carpal and metacarpal of thumb of the hand.
A ball-and-socket joint is the most freely movable of all joints. e.g., shoulder and hip joints.