Which nerve innervates the biceps and brachialis and provides elbow flexion and sensation over the lateral forearm?

Which nerve innervates the biceps and brachialis and provides elbow flexion and sensation over the lateral forearm?

• A. Median nerve
• B. Musculocutaneous nerve
• C. Ulnar nerve
• D. Radial nerve

Answer: (B)

This item tests knowing which nerve provides the main elbow flexors and the lateral forearm sensation. The biceps brachii and brachialis are the primary elbow flexors in the arm, and they receive motor input from the musculocutaneous nerve. This nerve also gives off the lateral antebrachial cutaneous branch, which supplies sensation to the lateral forearm. So it matches both the motor action (elbow flexion) and the sensory area (lateral forearm). The median nerve mainly innervates many forearm flexors and some hand muscles, with sensory distribution in the palm and digits rather than the lateral forearm. The ulnar nerve supplies the medial forearm and most intrinsic hand muscles. The radial nerve supplies the posterior arm and forearm extensors and provides sensation on the dorsolateral hand, not the lateral forearm.

This item tests knowing which nerve provides the main elbow flexors and the lateral forearm sensation. The biceps brachii and brachialis are the primary elbow flexors in the arm, and they receive motor input from the musculocutaneous nerve. This nerve also gives off the lateral antebrachial cutaneous branch, which supplies sensation to the lateral forearm. So it matches both the motor action (elbow flexion) and the sensory area (lateral forearm).

The median nerve mainly innervates many forearm flexors and some hand muscles, with sensory distribution in the palm and digits rather than the lateral forearm. The ulnar nerve supplies the medial forearm and most intrinsic hand muscles. The radial nerve supplies the posterior arm and forearm extensors and provides sensation on the dorsolateral hand, not the lateral forearm.