Ball-and-socket joint

This article is about bone joints. For ground glass joints, see Laboratory glassware.

Ball-and-socket joint
1: Ball and socket joint; 2: Condyloid joint (Ellipsoid); 3: Saddle joint; 4 Hinge joint; 5: Pivot joint;
Capsule of shoulder-joint (distended). Anterior aspect.
Details
Identifiers
Latin	articulatio spheroidea
TA98	A03.0.00.050
TA2	1562
FMA	75301
Anatomical terminology

A ball and socket joint (enarthrosis, spheroidal joint) is a joint in which the distal bone is capable of motion around an indefinite number of axes, which have one common center. It enables the bone to move in a 360° angle.

In a ball and socket (spheroid) joint, the ball-shaped surface of one rounded bone fits into the cup-like depression of another bone.

Examples

Examples of this form of articulation are found in the hip, where the rounded head of the femur (ball) rests in the cup-like acetabulum (socket) of the pelvis, and in the glenohumeral joint of the shoulder, where the rounded head of the humerus (ball) rests in the cup-like glenoid fossa (socket) of the shoulder blade. It should be noted that the shoulder includes a second joint as well which is a saddle joint.

Additional images

• 
  Hip
• 
  Shoulder

References

This article incorporates text in the public domain from page 287 of the 20th edition of Gray's Anatomy (1918)