Nerves of the arm in 3D

Course of the main nerves

The musculocutaneous nerve pierces coracobrachialis, supplies the anterior compartment of the arm and continues as the lateral antebrachial cutaneous nerve. The radial nerve winds around the back of the humerus in the radial groove and divides at the elbow into a superficial sensory branch and a deep branch, which becomes the posterior interosseous nerve to the extensors.

The median nerve runs with the brachial artery, supplies most forearm flexors directly and through the anterior interosseous nerve, and enters the hand through the carpal tunnel. The ulnar nerve passes behind the medial epicondyle, supplies flexor carpi ulnaris and the medial half of flexor digitorum profundus, and ends in superficial and deep branches in the hand.

What the 3D model shows

The model shows the nerves of the right upper limb with the skeleton as see-through context: the musculocutaneous, median, ulnar and radial nerves with their muscular, deep, superficial, palmar and dorsal branches; the anterior and posterior interosseous nerves; the muscular branches of the axillary nerve; the suprascapular, dorsal scapular and subscapular nerves; the brachial and antebrachial cutaneous nerves; and the digital branches to the fingers. A second view adds the limb muscles, so you can see which nerve reaches which muscle.

How to study the nerves of the arm

Start in the nerves view from the anterior side and pick out the median nerve in the middle of the limb and the ulnar nerve on the medial side, then turn to the posterior view to follow the radial nerve around the humerus. Switch to the nerves-and-muscles view, isolate one nerve and name every muscle it reaches. As a drill, say the nerve of each forearm muscle before you click it, then check the answer in the model.