Which of the following bilateral paired nerves innervates the buttocks and lower extremities?

• A. Trigeminal
• B. Peroneal
• C. Sciatic
• D. Vagus

Answer: (C)

The sciatic nerve is a crucial structure in the nervous system, particularly in its role of innervating the buttocks and lower extremities. As the largest nerve in the body, it emerges from the lower spine and travels down the back of the leg, branching into smaller nerves that supply the muscles and skin in the thighs, calves, feet, and toes.

The sciatic nerve is formed by the convergence of nerve roots from the lumbar and sacral regions (typically L4-S3), making it essential for both motor and sensory functions in the lower body. This includes control over movements of the hip, knee, and foot, as well as sensation in these areas, which is critical for mobility and overall function.

The other nerves mentioned in the choices serve different areas and functions. The trigeminal nerve primarily deals with sensation in the face and motor functions such as biting and chewing, making it unrelated to the lower body. The peroneal nerve, though it does provide some innervation to the lower extremity, is a branch of the sciatic nerve and doesn't innervate the buttocks. The vagus nerve mainly governs functions in the thoracic and abdominal cavities and does not contribute to the innervation of the lower extremities.