Washington Esthetician State Board Practice Exam

Which nerve is primarily responsible for supplying the arm and hand?

1. Radial nerve

2. Median nerve

3. Ulnar nerve

4. Musculocutaneous nerve

The correct answer is: Median nerve

The median nerve is primarily responsible for supplying the arm and hand. It plays a crucial role in the movement and sensation of the forearm and hand, especially in relation to the flexor muscles and some of the intrinsic muscles of the hand. This nerve innervates most of the flexor muscles in the forearm and the thenar muscles (the muscles at the base of the thumb) as well as the lateral two lumbrical muscles, allowing for fine motor skills like pinching and grasping. Understanding the median nerve's function is key for professionals in the field, particularly in recognizing conditions like carpal tunnel syndrome, where this nerve can become compressed, leading to symptoms such as numbness, tingling, and weakness in the hand. The radial, ulnar, and musculocutaneous nerves also supply parts of the arm and hand, but the median nerve is the one most directly involved in the sensation and motor function of the anterior forearm and the majority of the hand.