After receiving inputs from both the lateral and medial cords of the brachial plexus, the median nerve enters the arm from the axilla at the inferior margin of the teres major muscle.

Inside the cubital fossa, the median nerve passes medial to the brachial artery.

A branch to pronator teres muscle arise from the median nerve immediately above the elbow joint.

[3] The main trunk of the median nerve innervates the superficial and deep groups of the muscles in the anterior compartment of the forearm with the exception of flexor carpi ulnaris.

The palmar cutaneous branch of the median nerve arises at the distal part of the forearm.

Injury of median nerve at different levels causes different syndromes with varying motor and sensory deficits.

At the shoulder Above the elbow At the elbow Within the proximal forearm: anterior interosseous syndrome At the wrist Within the wrist: carpal tunnel syndrome When symptoms of tingling, numbness, pain, or muscle weakness occur, various assessments are conducted, including patient-reported subjective surveys, provocative tests meant to elicit or exacerbate symptoms, sensory and motor function tests, and diagnostic equipment.

Combinations of these assessments are useful for ruling out other conditions, identifying the location of nerve injury or compression, uncovering underlying causes of symptoms (such as tendonitis), determining the severity of the nerve injury, and developing individualized treatment plans based on patient characteristics.

[16] Such combinations of median nerve evaluations have been most widely validated in the assessment of carpal tunnel syndrome.