Tarsal tunnel syndrome

Tarsal tunnel syndrome is a compression neuropathy of the posterior tibial nerve within the tarsal tunnel. Trauma is the most common cause, but other causes include inflammatory disease, bony malformations, and tumors. Manifestations include neuropathic pain, paresthesia, and numbness (which worsen with activity) in the posteromedial ankle, heel, and toes. Muscle atrophy may be present in severe cases. On examination, symptoms may be reproducible on provocative tests (e.g., tinel sign, dorsiflexion-eversion test). Diagnostics include imaging and electrodiagnostic tests to confirm the diagnosis and rule out differential diagnoses of chronic heel pain. Tarsal tunnel syndrome is generally managed conservatively, with surgery reserved for refractory cases.

Neuropathy caused by compression of the posterior tibial nerve or its branches within the tarsal tunnel ^[1][2]

• Trauma (most common): fracture or sprain of the ankle (talus, calcaneus, medial malleolus)
• Rheumatoid arthritis
• Bone spurs
• Tumors
• Cysts
• Nerve ganglions
• Biomechanical abnormalities of the foot (e.g., pes planus)
• Idiopathic

• Sensory symptoms ^[1][2]
  • Develop in areas innervated by the tibial nerve (i.e., posteromedial ankle, heel, medial longitudinal arch, and toes)
    • Neuropathic pain
    • Paresthesia
    • Numbness
  • Worsen with activity (e.g., walking, running) and standing
  • Better with rest and elevation
• Muscle atrophy: in severe cases ^[1][2]

• Clinical evaluation: pain or paresthesia elicited on provocative tests ^[1][2]
  • Tinel sign: percussion over the tibial nerve posterior to the medial malleolus
  • Dorsiflexion with eversion of the foot
  • Plantar flexion with inversion of the foot
• Confirmatory testing: Consider specialist referral (e.g., neurology, podiatry).^[1][2][3]
  • X-ray foot (consider weight-bearing x-rays) should be obtained in all patients to:
    • Evaluate for an underlying bony etiology
    • Rule out common differential diagnoses of chronic heel pain
  • Ultrasound foot or MRI foot without IV contrast: to confirm compression of the posterior tibial nerve or its branches ^[3]
  • Electrodiagnostic studies (e.g., electromyography, nerve conduction studies): Consider in case of diagnostic uncertainty. ^[1]

Tarsal tunnel syndrome is generally managed conservatively, with surgery reserved for refractory cases. For athletes, see “Compression neuropathies in sport.”

• Conservative treatment: Options include ^[1]
  • Nonpharmacological treatment, e.g., rest, orthotic shoes, modification of daily activities, physical therapy
  • Pharmacological treatment, e.g.:
    • NSAIDs (oral or topical)
    • Adjuvant analgesia (i.e., tricyclic antidepressant and antiepileptics)
    • Ultrasound-guided corticosteroid injection
• Surgical treatment : Consider for individuals with refractory symptoms. ^[1][2]