Which nerve innervates both the iliacus and sartorius muscles?

Which nerve innervates both the iliacus and sartorius muscles?

• A. Femoral
• B. Obturator
• C. Sciatic
• D. Superior gluteal

Answer: (A)

Front thigh muscles in the anterior compartment share the same primary nerve supply, the femoral nerve. The iliacus and sartorius both lie in this compartment and receive innervation from the femoral nerve (L2–L4), which travels under the inguinal ligament to reach the thigh. The iliacus contributes to hip flexion as part of the iliopsoas, while the sartorius crosses the thigh to its pes anserinus insertion and also helps flex the hip (and knee). Because both muscles are innervated by the femoral nerve, this nerve uniquely accounts for their motor innervation. The other nerves listed supply different muscle groups (obturator to most medial thigh muscles, sciatic to the posterior compartment and leg, and superior gluteal to gluteal muscles), so they don’t innervate both iliacus and sartorius.

Front thigh muscles in the anterior compartment share the same primary nerve supply, the femoral nerve. The iliacus and sartorius both lie in this compartment and receive innervation from the femoral nerve (L2–L4), which travels under the inguinal ligament to reach the thigh. The iliacus contributes to hip flexion as part of the iliopsoas, while the sartorius crosses the thigh to its pes anserinus insertion and also helps flex the hip (and knee). Because both muscles are innervated by the femoral nerve, this nerve uniquely accounts for their motor innervation. The other nerves listed supply different muscle groups (obturator to most medial thigh muscles, sciatic to the posterior compartment and leg, and superior gluteal to gluteal muscles), so they don’t innervate both iliacus and sartorius.