A 24-year-old man presents after an anterior dislocation of the shoulder that was reduced in the emergency department. He now has anaesthesia over the lateral aspect of the shoulder ('regimental badge' area). Which structure has been injured?

• A Suprascapular nerve
• B Musculocutaneous nerve
• C Upper trunk of the brachial plexus
• D Axillary nerve ✓

Explanation

The axillary nerve is the most commonly injured nerve in anterior shoulder dislocation because it wraps around the surgical neck of the humerus. It supplies the deltoid and the skin over the lower half of the deltoid, producing the regimental badge sensory loss. The suprascapular nerve supplies supraspinatus and infraspinatus without cutaneous territory, and musculocutaneous injury causes weak elbow flexion with lateral forearm numbness.

Reference: Apley's System of Orthopaedics and Fractures, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.