Median nerve
Nervus medianus
NervousNervesArmLeft and right
View left in 3D View right in 3D
- What it is
- Formed by the lateral and medial cords in front of the axillary artery, it runs down the medial side of the arm with the brachial artery, enters the forearm between the heads of pronator teres, descends in the middle of the forearm between the superficial and deep finger flexors and passes through the carpal tunnel into the palm.
- Function
- Motor to most forearm flexors and both pronators, the thenar muscles and the two lateral lumbricals; sensation from the palm side of the thumb, index, middle and half of the ring finger.
- Size
- About 4 mm thick in the arm; ~60 cm from the axilla to the fingertips
- Clinical note
- Carpal tunnel syndrome - compression under the flexor retinaculum - causes night-time tingling in the thumb-to-ring fingers and wasting of the thumb ball; a supracondylar fracture in a child can injure it higher up.