Which nerve innervates both Inferior Gemellus and Quadratus Femoris?

Which nerve innervates both Inferior Gemellus and Quadratus Femoris?

• A. Nerve to Quadratus Femoris
• B. Nerve to Obturator Internus
• C. Femoral Nerve
• D. Superior Gluteal Nerve

Answer: (A)

The key idea is that the deep lateral rotators of the hip have distinct nerve supplies from the sacral plexus. The nerve to quadratus femoris supplies both the Quadratus Femoris and the Inferior Gemellus, giving motor innervation to these two muscles. This nerve carries fibers from L4 to S1 and travels directly to these muscles to enable lateral rotation of the thigh when the hip extends. Other nerves listed map to different muscles: the nerve to obturator internus goes to the Obturator Internus and typically the Superior Gemellus, the Femoral Nerve innervates the anterior thigh muscles, and the Superior Gluteal Nerve supplies the Gluteus Medius and Minimus. So, the shared innervation of Inferior Gemellus and Quadratus Femoris by the nerve to quadratus femoris is the best explanation for why both are supplied by the same nerve.

The key idea is that the deep lateral rotators of the hip have distinct nerve supplies from the sacral plexus. The nerve to quadratus femoris supplies both the Quadratus Femoris and the Inferior Gemellus, giving motor innervation to these two muscles. This nerve carries fibers from L4 to S1 and travels directly to these muscles to enable lateral rotation of the thigh when the hip extends. Other nerves listed map to different muscles: the nerve to obturator internus goes to the Obturator Internus and typically the Superior Gemellus, the Femoral Nerve innervates the anterior thigh muscles, and the Superior Gluteal Nerve supplies the Gluteus Medius and Minimus. So, the shared innervation of Inferior Gemellus and Quadratus Femoris by the nerve to quadratus femoris is the best explanation for why both are supplied by the same nerve.