During the axillary approach to the brachial plexus, the block is performed in the axilla, where large terminal branches have formed. At this point, the musculocutaneous nerve lies deep within the coracobrachialis, having already left the proximity of the other nerves. A separate block is essential to complete forearm and wrist anesthesia. The musculocutaneous nerve can be blocked by redirecting the needle, after completing the axillary block, superiorly and posteriorly to pierce and inject anesthetic within the coracobrachialis. The nerve can also be blocked by injecting anesthetic at the interepicondylar line at the elbow where the nerve courses superficially.
The musculocutaneous nerve is important because it gives rise to the lateral cutaneous nerve of the forearm.