3rd and 4th lumbrical (lateral two lumbricals) of foot are supplied by –
## **Core Concept**
The lumbrical muscles in the foot are innervated by branches of the **tibial nerve**, which is a part of the **L5-S2** nerve roots. These muscles play a crucial role in toe movements.
## **Why the Correct Answer is Right**
The lateral two lumbricals (3rd and 4th) in the foot are supplied by the **deep branch of the lateral plantar nerve**, a branch of the **tibial nerve**. This nerve provides motor innervation to these muscles, enabling toe flexion and extension. The lateral plantar nerve arises from the **tibial nerve** in the foot.
## **Why Each Wrong Option is Incorrect**
* **Option A:** Incorrect because the **medial plantar nerve** typically supplies the medial two lumbricals (1st and 2nd).
* **Option B:** Incorrect as it is not specified but generally refers to a nerve not primarily responsible for the lateral two lumbricals.
* **Option D:** Incorrect because the **superficial peroneal nerve** primarily supplies muscles in the lateral compartment of the leg, not the lumbricals in the foot.
## **Clinical Pearl / High-Yield Fact**
A key point to remember is that the lumbrical muscles in the foot are crucial for toe movements and are innervated by the **lateral and medial plantar nerves**, which are branches of the **tibial nerve**. Damage to these nerves can lead to toe movement abnormalities.
## **Correct Answer:** C. deep branch of lateral plantar nerve.