Which of the following structures is most likely injured in this patient? A 23-year old woman is brought to the emergency department 45 minutes after sustaining an injury to her right shoulder when she was forcefully thrown into a swimming pool. The patient is holding her right ARM in external rotation. There is an area of tenderness and absent sensation over the lateral aspect of the forearm. Immediately after reduction of the glenohumeral joint, she is unable to flex the elbow against gravity.
A. Axillary nerve B. Musculocutaneous nerve C. Posterior cord of the brachial plexus D. Radial nerve E. Thoracodorsal nerve
The Musculocutaneous Nerve (C5-C7) innervates the flexors in the arm- the biceps brachii, brachialis, and Coracobrachialis. It then travels to the lateral forearm where it provides cutaneous innervation.