Professional and Linguistic Assessments Board (PLAB) Practice Exam

Loss of sensation in the lateral leg is associated with which nerve?

1. Sural nerve

2. Saphenous nerve

3. Femoral nerve

4. Obturator nerve

The correct answer is: Sural nerve

The loss of sensation in the lateral leg is primarily associated with the sural nerve. This nerve is a sensory nerve that arises from the sciatic nerve and supplies sensations to the skin of the lateral aspect of the leg and the lateral side of the foot. When there is damage or compression to the sural nerve, it can result in numbness or a loss of feeling in the areas it innervates, which explains the sensory loss in the lateral leg. Understanding the anatomical course of the sural nerve and its sensory functions helps in accurately diagnosing the regions affected by potential nerve injuries. The other nerves mentioned do not typically provide sensation to the lateral leg. The saphenous nerve, while significant in leg sensation, primarily supplies the medial side of the leg and does not contribute to sensation on the lateral aspect. The femoral nerve primarily innervates the anterior thigh and is responsible for sensations in that region, while the obturator nerve mainly provides innervation to the medial thigh. Thus, the sural nerve is the correct answer for loss of sensation in the lateral leg.