## **Core Concept**
The deep peroneal nerve, also known as the anterior tibial nerve, is a branch of the common peroneal nerve. It provides motor innervation to the muscles of the anterior compartment of the leg and sensory innervation to specific areas of the foot. The nerve plays a crucial role in controlling ankle dorsiflexion and toe extension.

## **Why the Correct Answer is Right**
The deep peroneal nerve provides sensory innervation to the **first web space** of the foot, which is the area between the first and second toes. This is a key clinical landmark for assessing the function of the deep peroneal nerve. The sensory innervation is primarily through the terminal branches of the deep peroneal nerve, which form the medial and lateral dorsal cutaneous nerves of the foot, with a specific focus on the first web space.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Incorrect because the specific areas innervated by the deep peroneal nerve do not include the lateral side of the leg; that is more associated with the superficial peroneal nerve.
- **Option B:** Incorrect as the deep peroneal nerve does not provide sensory innervation to the medial side of the leg; the saphenous nerve, a branch of the femoral nerve, provides sensation to this area.
- **Option C:** Incorrect because, although the deep peroneal nerve does provide sensation to part of the foot, option D specifically identifies the correct area (the first web space), making it the accurate choice.

## **Clinical Pearl / High-Yield Fact**
A key clinical correlation is that damage to the deep peroneal nerve can result in **foot drop**, characterized by an inability to dorsiflex the foot, and sensory loss in the first web space. This condition often leads to a compensatory mechanism where patients use a higher step to avoid tripping.

## **Correct Answer:** D. First web space.