Innervation Motor none Sensory radial forearm Reflexes none Origin C5,6,7 roots brachial plexus musculocutaneous nerve Course of Lateral Antebrachial Cutaneous Nerve Originates from the musculocutaneous nerve Passes behind the cephalic vein Pierces the deep fascia lateral to the biceps tendon Divides at the level of the elbow joint into volar and dorsal branches Terminal Branches Volar runs distally along radial border of forearm, supplying lateral volar forearm skin sensation small branches innervate the radial aspect of radiocarpal joint ends in communicating branches to: superficial branch of the radial nerve (dorsal radial thumb innervation) palmar cutaneous branch of median nerve (volar radial thumb innervation) Dorsal runs distally along dorsal radial forearm, supplying dorsal-lateral cutaneous innervation ends in communicating branches: superficial radial nerve dorsal antebrachial cutaneous branch of radial nerve Nerve Injury & Clinical Conditions Injury results in loss of sensation along the radial aspect of the forearm