Which of the following muscles is primarily responsible for flexing the anterior wrist and hand?

• A. Extensor carpi ulnaris
• B. Triceps brachii
• C. Brachioradialis
• D. Flexor carpi radialis

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the function of flexion in the anterior wrist and hand. Flexion refers to the movement that decreases the angle between the bones of the joint, bringing the palm closer to the forearm.
2. Step 2: Review the anatomy of the muscles listed in the options. The Extensor carpi ulnaris is responsible for wrist extension and ulnar deviation, not flexion. The Triceps brachii is involved in elbow extension, and the Brachioradialis assists in forearm flexion but does not flex the wrist.
3. Step 3: Focus on the Flexor carpi radialis. This muscle is located on the anterior side of the forearm and is primarily responsible for flexing the wrist and aiding in radial deviation (movement toward the thumb side).
4. Step 4: Relate the muscle's name to its function. 'Flexor' indicates its role in flexion, 'carpi' refers to the wrist, and 'radialis' points to its position near the radius bone.
5. Step 5: Conclude that the Flexor carpi radialis is the correct muscle responsible for flexing the anterior wrist and hand, based on its anatomical location and function.