In a patient with tarsal tunnel syndrome, which nerve is compressed and at what anatomical location?
- A Posterior tibial nerve under the flexor retinaculum behind the medial malleolus ✓
- B Deep peroneal nerve under the extensor retinaculum at the ankle
- C Sural nerve behind the lateral malleolus
- D Medial plantar nerve in the medial plantar canal
Correct answer: A. Posterior tibial nerve under the flexor retinaculum behind the medial malleolus
Explanation
Tarsal tunnel syndrome results from compression of the posterior tibial nerve (and its branches — medial and lateral plantar nerves, and calcaneal nerve) as it passes beneath the flexor retinaculum posterior to the medial malleolus. Patients present with burning pain, paraesthesia on the sole, and weakness of intrinsic foot muscles. It is analogous to carpal tunnel syndrome in the hand. The deep peroneal nerve compression is anterior tarsal tunnel syndrome (dorsum of foot); sural nerve is purely sensory.
Reference: BD Chaurasia's Human Anatomy, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.