Which nerve block is commonly used to anesthetize the anterior thigh region?

Which nerve block is commonly used to anesthetize the anterior thigh region?

• A. Obturator nerve block
• B. Femoral nerve block
• C. Saphenous nerve block
• D. Sciatic nerve block

Answer: (B)

The anterior thigh is primarily supplied by the femoral nerve, which carries both motor fibers to the quadriceps and sensory fibers to the front of the thigh. Blocking the femoral nerve at the inguinal region or within the femoral triangle interrupts these signals, producing anesthesia of the anterior thigh region as well as weakness of the quadriceps, which is expected with this block. Obturator nerve supplies the medial thigh, not the front, so its block would numb the inner thigh rather than the anterior surface. The saphenous nerve is a purely sensory branch of the femoral nerve that goes with the popliteal fossa down the medial leg; blocking it alone provides sensation changes in the medial leg, not the entire anterior thigh. The sciatic nerve covers the posterior thigh and everything below the knee, so it does not address the anterior thigh either.

The anterior thigh is primarily supplied by the femoral nerve, which carries both motor fibers to the quadriceps and sensory fibers to the front of the thigh. Blocking the femoral nerve at the inguinal region or within the femoral triangle interrupts these signals, producing anesthesia of the anterior thigh region as well as weakness of the quadriceps, which is expected with this block.

Obturator nerve supplies the medial thigh, not the front, so its block would numb the inner thigh rather than the anterior surface. The saphenous nerve is a purely sensory branch of the femoral nerve that goes with the popliteal fossa down the medial leg; blocking it alone provides sensation changes in the medial leg, not the entire anterior thigh. The sciatic nerve covers the posterior thigh and everything below the knee, so it does not address the anterior thigh either.