200 Section - Plantar fasciitis as an initial diagnosis of tarsal tunnel syndrome: Case report

Case Diagnosis: Tarsal Tunnel Syndrome (TTS) is a rare kind of neuropathy caused by  entrapment of posterior tibial nerve deep to the flexor retinaculum on the medial side of the ankle. It can cause chronic pain, paresthesia, and muscle weakness.

Case Description: A female patient aged 62 years presented stabbing pain in the soles of her feet. The pain sometimes radiated to the ankle and was worse while walking. She was first diagnosed with plantar fasciitis and was treated with physiotherapy, analgesics, and shockwave therapy without any benefit. When she saw a physical medicine and rehabilitation specialist, she stated that she had tingling in the soles as a new symptom.

The physical examination showed atrophic intrinsic plantar muscles and hypoesthesia in medial and lateral plantar nerves territories in the right foot. Ultrasound revealed thickening of the tibial nerve. Electrodiagnostic tests exhibited reduced amplitude of the tibial nerve compound motor action potential (CMAP) and there was no response on the sensory nerve conduction study of the plantar nerves. Electromyography showed denervation in the abductor hallucis muscle.

Discussions: Based on these findings, a diagnosis of TTS was made. The patient was sent to orthopedic surgery and had surgical decompression. After surgery, her pain and neurologic symptoms improved a lot.

Foot pain can be derived from multiple causes. Therefore, appropriate neuromusculoskeletal and neurologic evaluation is key to diagnosis.  Proper approach highlights the importance of physical medicine and rehabilitation specialist, as this specialty brings together knowledge in anatomy, ultrasonography, and neurophysiology.

Conclusions: This case also highlights the need for a re-evaluation of the diagnosis in patients not responding to conventional treatment.