Ball-and-socket joint

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== Ball-and-socket joint ==

A ball-and-socket joint (or spheroidal joint) is a type of synovial joint in which the ball-shaped surface of one rounded bone fits into the cup-like depression of another bone. This arrangement allows for a wide range of movement in almost all directions, including flexion, extension, abduction, adduction, and rotation.

Structure

The ball-and-socket joint consists of a spherical head (the ball) that fits into a rounded cavity (the socket). The articular cartilage covering the surfaces of the bones reduces friction and absorbs shock. The joint is enclosed by a joint capsule lined with synovial membrane that secretes synovial fluid for lubrication.

Function

Ball-and-socket joints allow for the most extensive range of motion of all joint types. They are capable of multiaxial movement, meaning they can move in multiple planes. This makes them crucial for activities that require a high degree of flexibility and mobility.

Examples

The most well-known examples of ball-and-socket joints in the human body are the shoulder joint and the hip joint.

• The shoulder joint (glenohumeral joint) is formed by the articulation of the humerus with the glenoid cavity of the scapula.
• The hip joint (acetabulofemoral joint) is formed by the articulation of the femur with the acetabulum of the pelvis.

Clinical Significance

Ball-and-socket joints are susceptible to various injuries and conditions, such as dislocation, arthritis, and bursitis. Proper functioning of these joints is essential for maintaining mobility and performing daily activities.

Related Joints

Other types of synovial joints include:

• Hinge joint
• Pivot joint
• Saddle joint
• Condyloid joint
• Plane joint

See Also

• Joint
• Synovial joint
• Articular cartilage
• Ligament
• Tendon