A football player has suffered severe trauma to the lateral pa of the left leg just below the knee. He drags his left toe when he walks and cannot feel the dorsum of the foot. Which of the following will still be intact
**Core Concept**
The football player's symptoms suggest a severe injury to the common peroneal nerve or its branches, which are responsible for innervating the muscles responsible for foot and toe movements. The common peroneal nerve is a branch of the sciatic nerve that arises from the L4-S2 nerve roots.
**Why the Correct Answer is Right**
The common peroneal nerve innervates the muscles involved in dorsiflexion (lifting the foot up) and eversion (rotating the foot outwards). Since the player cannot feel the dorsum of the foot, it suggests damage to the sensory branches of the common peroneal nerve. However, the muscles responsible for ankle movements, such as plantarflexion (pointing the foot down) and inversion (rotating the foot inwards), are innervated by the tibial nerve, a branch of the sciatic nerve. Therefore, the player's ability to move the ankle will still be intact, as it is controlled by a separate nerve.
**Why Each Wrong Option is Incorrect**
**Option A:** The player's inability to move the foot suggests damage to the nerves responsible for foot movements, making this option incorrect.
**Option B:** The player's symptoms are consistent with damage to the common peroneal nerve, not the tibial nerve, making this option incorrect.
**Option C:** The player's inability to feel the dorsum of the foot suggests damage to the sensory branches of the common peroneal nerve, not the motor branches, making this option incorrect.
**Option D:** The player's symptoms are consistent with damage to the nerves responsible for foot movements, not the nerves responsible for ankle movements, making this option incorrect.
**Clinical Pearl / High-Yield Fact**
Remember that the common peroneal nerve is the most superficial branch of the sciatic nerve and is therefore more susceptible to injury, especially when the knee is bent and the foot is everted.
**Correct Answer:** C.