Upper limb anatomy

Upper Limb Anatomy

The upper limb or upper extremity is the region in a vertebrate animal extending from the deltoid region up to and including the hand, which comprises the arm, forearm and hand. It includes bone, joints, ligaments, tendons, muscles, nerves, and blood vessels.

Bones

The bones of the upper limb, from proximal to distal, are the humerus, the ulna and radius, and the carpal bones, metacarpal bones, and phalanges.

Humerus

The humerus is the bone of the upper arm. It articulates with the scapula to form the shoulder joint, and with the radius and ulna to form the elbow joint.

Ulna and Radius

The ulna and radius are the two bones of the forearm. The ulna is medial and larger, and the radius is lateral and smaller. They articulate with the humerus to form the elbow joint.

Carpal Bones

The carpal bones are the eight small bones that make up the wrist, or carpus. They articulate with the ulna and radius to form the wrist joint.

Metacarpal Bones

The metacarpal bones are the five long bones in the hand. They articulate with the carpal bones and the phalanges.

Phalanges

The phalanges are the 14 bones that make up the fingers. Each finger has three phalanges, except for the thumb, which has two.

Joints

The joints of the upper limb include the shoulder joint, the elbow joint, the wrist joint, and the interphalangeal joints.

Muscles

The muscles of the upper limb are divided into the muscles of the shoulder, the muscles of the arm, and the muscles of the forearm and hand.

Nerves

The main nerves of the upper limb are the brachial plexus, the radial nerve, the ulnar nerve, and the median nerve.

Blood Vessels

The main blood vessels of the upper limb are the subclavian artery and vein, the axillary artery and vein, and the brachial artery and vein.

See Also

• Lower limb anatomy
• Human skeleton
• Muscular system
• Nervous system
• Circulatory system