Nerves and Blood Vessels of the Arm: Origin, Course, Relations, and Branches

Introduction

The human arm is supplied by a complex network of nerves and blood vessels that enable movement, sensation, and circulation. This blog explores the major components, their origin, course, relations, and branches.

Major Nerves of the Arm

Brachial Plexus

The brachial plexus is a network of nerves originating from C5-T1 spinal roots. It divides into trunks, divisions, and cords, ultimately giving rise to major nerves of the arm.

Radial Nerve

Arising from the posterior cord of the brachial plexus, the radial nerve supplies the extensor muscles of the arm and forearm, passing through the spiral groove of the humerus.

Median Nerve

Formed by contributions from the lateral and medial cords, the median nerve controls forearm flexors and intrinsic hand muscles, passing through the carpal tunnel.

Ulnar Nerve

Originating from the medial cord of the brachial plexus, the ulnar nerve supplies the flexor carpi ulnaris and intrinsic hand muscles, passing posterior to the medial epicondyle.

Major Blood Vessels of the Arm

Brachial Artery

The brachial artery is the main arterial supply to the arm, continuing from the axillary artery and bifurcating into the radial and ulnar arteries.

Radial Artery

A continuation of the brachial artery, the radial artery supplies the lateral forearm and hand, commonly used for pulse measurement.

Ulnar Artery

The ulnar artery provides blood supply to the medial forearm and hand, contributing to palmar circulation through anastomoses.

Conclusion

The arm’s neurovascular system is crucial for movement, sensation, and blood flow. Understanding its structure helps in diagnosing and managing related medical conditions.