Which nerve is not derived from the sciatic nerve and contributes to sensation of the foot?

Which nerve is not derived from the sciatic nerve and contributes to sensation of the foot?

• A. Deep peroneal nerve
• B. Superficial peroneal nerve
• C. Sural nerve
• D. Saphenous nerve

Answer: (D)

The important idea is that the sciatic nerve splits into tibial and common fibular branches, and most nerves that provide sensation to the foot come from those branches. The deep peroneal and superficial peroneal nerves are branches of the common fibular nerve, and the sural nerve is formed from contributions of both tibial and common fibular nerves—so these are all ultimately from the sciatic nerve. The saphenous nerve, however, comes from the femoral nerve and supplies the medial aspect of the leg and foot, not via the sciatic trunk. So, while it does carry sensation from parts of the foot, it is not derived from the sciatic nerve.

The important idea is that the sciatic nerve splits into tibial and common fibular branches, and most nerves that provide sensation to the foot come from those branches. The deep peroneal and superficial peroneal nerves are branches of the common fibular nerve, and the sural nerve is formed from contributions of both tibial and common fibular nerves—so these are all ultimately from the sciatic nerve. The saphenous nerve, however, comes from the femoral nerve and supplies the medial aspect of the leg and foot, not via the sciatic trunk. So, while it does carry sensation from parts of the foot, it is not derived from the sciatic nerve.