Which nerve innervates gracilis?

Which nerve innervates gracilis?

• A. Anterior division of obturator nerve
• B. Femoral nerve
• C. Obturator nerve
• D. Tibial nerve

Answer: (A)

Gracilis is a medial thigh muscle whose nerve supply comes from the anterior division of the obturator nerve. The obturator nerve, arising from the lumbar plexus (L2–L4), splits into anterior and posterior divisions within the thigh. The anterior division innervates the gracilis along with other medial thigh muscles like adductor longus and adductor brevis, whereas the posterior division supplies the adductor magnus (adductor part). Because gracilis is specifically innervated by the anterior division, that makes it the best and most precise choice. The other options don’t fit because the femoral nerve mainly supplies muscles of the anterior thigh, the tibial nerve supplies most posterior compartment muscles of the leg (and the hamstring part of adductor magnus), and while the obturator nerve does innervate gracilis, it is the anterior division that does so, not the nerve as a whole.

Gracilis is a medial thigh muscle whose nerve supply comes from the anterior division of the obturator nerve. The obturator nerve, arising from the lumbar plexus (L2–L4), splits into anterior and posterior divisions within the thigh. The anterior division innervates the gracilis along with other medial thigh muscles like adductor longus and adductor brevis, whereas the posterior division supplies the adductor magnus (adductor part). Because gracilis is specifically innervated by the anterior division, that makes it the best and most precise choice.

The other options don’t fit because the femoral nerve mainly supplies muscles of the anterior thigh, the tibial nerve supplies most posterior compartment muscles of the leg (and the hamstring part of adductor magnus), and while the obturator nerve does innervate gracilis, it is the anterior division that does so, not the nerve as a whole.