Certified Neuroscience Registered Nurse (CNRN) Practice Exam

A recently immobilized patient complains of burning on the top of the foot along with unilateral foot drop. What condition is this indicative of?

1. Peroneal nerve palsy

2. Tarsal tunnel syndrome

3. Achilles tendon rupture

4. Anterior compartment syndrome

The correct answer is: Peroneal nerve palsy

The presentation of burning sensations on the top of the foot along with unilateral foot drop suggests peroneal nerve palsy. The peroneal nerve, a branch of the sciatic nerve, innervates muscles responsible for foot dorsiflexion and eversion. When this nerve is injured or compressed, it results in a characteristic foot drop, where the patient has difficulty lifting the front part of the foot, often leading to dragging of the toes while walking. The burning sensation indicates possible irritation or dysfunction of the nerve, which can occur due to compression in various contexts, including prolonged pressure during immobilization. Such compression might arise from the position of the leg or the application of a cast or brace. The other conditions mentioned do not directly correlate with the combination of symptoms described. Tarsal tunnel syndrome would be more likely to present with numbness or pain in the distribution of the tibial nerve rather than a complete drop-foot presentation. An Achilles tendon rupture generally involves pain and difficulty with plantarflexion rather than foot drop. In anterior compartment syndrome, the individual would likely experience severe pain, swelling, and other symptoms related to the muscle compartments but not the specific symptom pattern of burning on the dorsum of the foot and foot drop.