Q.Name the type of joint between the following:

The types of joint are:

• (a) atlas/axis — pivot joint (a synovial joint).
• (b) carpal/metacarpal of the thumb — saddle joint (a synovial joint).
• (c) between phalanges — hinge joint (a synovial joint).
• (d) femur/acetabulum — ball and socket joint (a synovial joint).
• (e) between cranial bones — fibrous joint (sutures, allowing no movement). …

Joints are the points of contact between two bones, or between a bone and a cartilage, and they are grouped by structure into fibrous, cartilaginous and synovial types. Synovial joints, which have a fluid-filled cavity between the articulating surfaces, allow considerable movement and come in several named forms.

• (a) atlas/axis — pivot joint. The joint between the first two vertebrae, the atlas and the axis, is a synovial pivot joint, permitting a rotational movement.
• (b) carpal/metacarpal of the thumb — saddle joint. The joint between the carpal and the metacarpal of the thumb is a synovial saddle joint.
• (c) between phalanges — hinge joint. The joints between the finger and toe bones are hinge joints, of the same kind as the knee, allowing movement in one plane.
• (d) femur/acetabulum — ball and socket joint. The rounded head of the femur fits into the cup-shaped acetabulum of the pelvic girdle, forming a synovial ball and socket joint that allows movement in many directions. …