Which nerve provides innervation to supraspinatus and infraspinatus?

• A. Axillary nerve
• B. Radial nerve
• C. Suprascapular nerve
• D. Dorsal scapular nerve

Answer: (C)

The nerve that innervates both supraspinatus and infraspinatus is the suprascapular nerve. This nerve arises from the upper trunk of the brachial plexus (typically C5–C6) and travels to the shoulder through the suprascapular notch. It sends motor branches to the supraspinatus in the supraspinous fossa, then continues around the scapular spine through the spinoglenoid notch to supply the infraspinatus as well. Because a single nerve supplies both muscles, it can coordinate the initial broadening of the arm (supraspinatus initiating abduction) and the external rotation provided by the infraspinatus. The other nerves listed do not innervate both of these muscles.