Joints Formed by Specific Bones

Major Joints of the Upper Limb

The upper limb consists of several major joints that facilitate movement and functionality. These joints include the shoulder, elbow, and wrist, each formed by specific bones and supported by ligaments, muscles, and cartilage.

1. Shoulder Joint

Structure and Function

The shoulder joint, also known as the glenohumeral joint, is a ball-and-socket joint formed by the humerus and the scapula. This joint provides extensive mobility, allowing movements such as flexion, extension, abduction, adduction, and rotation.

Key Components

• Humerus: The upper arm bone that fits into the glenoid cavity of the scapula.
• Scapula: The shoulder blade, providing the socket for the humerus.
• Clavicle: The collarbone, supporting shoulder movement.
• Rotator Cuff Muscles: Stabilize and aid in shoulder mobility.

2. Elbow Joint

Structure and Function

The elbow joint is a hinge joint that connects the humerus, radius, and ulna. It allows flexion and extension movements.

Key Components

• Humerus: The upper arm bone forming the hinge with the radius and ulna.
• Radius: The lateral forearm bone aiding rotation.
• Ulna: The medial forearm bone supporting flexion and extension.
• Ligaments: Provide structural support.

3. Wrist Joint

Structure and Function

The wrist joint comprises multiple bones, including the radius, ulna, and carpal bones. It allows various movements, including flexion, extension, and circumduction.

Key Components

• Radius & Ulna: Form the wrist joint with the carpal bones.
• Carpal Bones: Eight small bones providing structural complexity.
• Ligaments: Enhance stability and movement.
• Tendons: Connect muscles to bones for motion.