Which of the following nerves innervates the deltoid?

Question

Options

• ARadial
• BCranial nerve XI
• CSubscapular
• DAxillary

• A
  13% (4)
• B
  3% (1)
• C
  10% (3)
• D
  73% (22)

Explanation

The axillary nerve (C5-C6), a branch of the posterior cord of the brachial plexus, innervates the deltoid muscle along with the teres minor. The radial nerve (A) innervates the posterior compartment of the arm and forearm (extensors), not the deltoid. Cranial nerve XI (B) (accessory nerve) innervates the trapezius and sternocleidomastoid - it's a common distractor because the trapezius and deltoid both cap the shoulder. The subscapular nerve (C) innervates the subscapularis and teres major, not the deltoid.

Memory tip: Think "Axillary nerve = Abduction" - the deltoid is the prime mover of shoulder abduction, and both start with A. Alternatively, recall that the axillary nerve wraps around the surgical neck of the humerus, right beneath the deltoid it supplies.

No community discussion yet for this question.