Median Nerve


 * It is formed by the union of radix medialis nervi mediani (from fasciculus medialis plexus brachialis) and radix lateralis nervi mediani (from fasciculus lateralis pl. brachialis). Root innervation is C5–Th1.
 * Descends along the brachial artery in front of the septum intermusculare brachii mediale.
 * Does not send out any branches on the arm
 * In the regio cubiti, it passes between the caput humerale and ulnare musculi pronatoris teretis (canalis pronatorius in depth and continues on the forearm between m. flexor digitorum superficialis and profundus).
 * In the distal third of the forearm, it is placed superficially under the fascia antebrachii between the m. palmaris longus and m. flexor carpi radialis tendons, continues under the retinaculum musculorum flexorum to the canalis carpi.
 * In the canalis carpi, it is located just below the retinaculum, lateral to the m. flexor digitorum superficialis tendons.
 * After leaving the canalis carpi, it enters the palm (spatium palmare medium).

Branches on forearm and hand

 * Rami musculares - for m. pronator teres, m. flexor carpi radialis, m. palmaris longus and m. flexor digitorum superficialis.
 * Nervus interosseus antebrachii anterior - descends along the front surface of the membrana interossea, innervates the m. flexor pollicis longus, m. flexor digitorum profundus (for the part of the muscle intended for the 2nd and 3rd fingers) and for m. pronator quadratus.
 * Ramus palmaris n. mediani - a weak branch for the skin of the radial half of the carpal landscape and extends to the palm.
 * Nervi digitales palmares (volares) communes I., II., III., – final branches of n. medianus in the palm, located above the flexor tendons and below the arterial arcus palmaris superficialis, project over the first to third intermetacarpal space, innervate most of the thenar muscles (+ the first 2 mm. lumbricales) and the greater part of the skin of the palm from the thumb side, at the base of the fingers, it divides in a fork-like manner into nervi digitales palmares proprii - sensitive skin branches lining the adjacent sides of the thumb, index finger, middle finger and the radial side of the ring finger, the innervation area extends to the dorsal side of the nail joints of the fingers.


 * N. digitalis palmaris communis I. - gives off branches for thenar muscles (m. abductor pollicis brevis, caput superficiale m. flexor pollicis brevis, m. opponens pollicis), 3 skin branches - nn. digitales palmares proprii for both edges of the thumb and for the radial edge of the index finger.


 * N. digitalis palmaris communis II. - gives off a muscular branch for m. lumbricalis I. and cutaneous nn. digitales palmares proprii for the ulnar edge of the index finger and radial edge 3 .finger.


 * N. digitalis palmaris communis III. - innervates m. lumbricalis II. and gives off the skin nn. digitales palmares proprii for the ulnar edge of the 3rd finger and the radial edge of the 4th finger, the skin on the dorsal side of the nail joints 1st-3rd. finger and partly also the 4th finger.

Related Articles

 * Median nerve palsy