Tarsal Tunnel Syndrome: Symptoms, Causes & Treatment

Tarsal tunnel syndrome (TTS) is a compression neuropathy of the posterior tibial nerve as it passes through the tarsal tunnel — a narrow passage on the inside of the ankle beneath the flexor retinaculum. Often called the “carpal tunnel syndrome of the foot,” TTS causes burning, tingling, and shooting pain along the bottom of the foot and toes. It’s frequently misdiagnosed as plantar fasciitis, making accurate diagnosis critical.

The Tarsal Tunnel: Anatomy Explained

The tarsal tunnel is formed by the medial malleolus (inside ankle bone), the heel bone (calcaneus), and a thick band of fibrous tissue called the flexor retinaculum. Running through this tunnel are the posterior tibial nerve, artery, vein, and four tendons. When any structure in this confined space becomes enlarged or the tunnel narrows, the tibial nerve is compressed.

The posterior tibial nerve divides inside the tunnel into three branches:

• Medial plantar nerve — supplies the inner half of the foot and first three toes
• Lateral plantar nerve — supplies the outer half of the foot and fourth and fifth toes
• Medial calcaneal nerve — supplies heel sensation

Which branches are affected determines the exact pattern of symptoms, helping podiatrists localize the compression site.

Tarsal Tunnel Syndrome Symptoms

Symptom	Pattern	Notes
Burning pain	Bottom of foot, heel, or toes	Often worse at night or after prolonged standing
Tingling/numbness	Follows nerve distribution into sole and toes	May be intermittent early, constant later
Electric shock sensation	Radiates into foot with Tinel sign at ankle	Highly specific for nerve compression
Weakness	Intrinsic foot muscles (toe spreading)	Advanced cases; results in toe deformity
Worsening with activity	Prolonged walking, running, standing	Unlike plantar fasciitis, may persist at rest

Tinel’s Sign: Tapping over the tarsal tunnel on the inside of the ankle reproduces the tingling/shooting sensation into the foot. This is the hallmark clinical test for TTS.

Tarsal Tunnel vs. Plantar Fasciitis: Key Differences

Feature	Tarsal Tunnel Syndrome	Plantar Fasciitis
Pain location	Inner ankle + diffuse plantar foot	Heel, especially plantar fascial insertion
Pain quality	Burning, tingling, electric	Aching, stabbing, tight
Morning pain	Less pronounced	Classic first-step pain
Nighttime pain	Common and often severe	Less common
Tinel sign	Positive (reproduces symptoms)	Negative
Nerve conduction study	Abnormal in 85-90% of cases	Normal
Treatment	Nerve decompression-focused	Mechanical offloading

Causes of Tarsal Tunnel Syndrome

• Space-occupying lesions — ganglion cyst, lipoma, varicose vein, or bone spur within the tunnel
• Flat feet (overpronation) — fallen arches cause the heel to tilt inward, stretching and compressing the tarsal tunnel
• Ankle trauma — post-sprain swelling, scar tissue, or altered mechanics can compress the nerve
• Systemic conditions — diabetes, hypothyroidism, rheumatoid arthritis increase nerve vulnerability
• Varicose veins — dilated veins within the tunnel reduce available space
• Pregnancy — fluid retention and relaxin-induced ligament laxity increase tarsal tunnel pressure
• Tight footwear — constrictive shoes pressing against the medial ankle

Diagnosis

• Clinical examination — Tinel’s sign, sensory mapping, muscle strength testing
• Nerve conduction study (NCS) / EMG — gold standard; demonstrates slowed conduction velocity across the tarsal tunnel; positive in 85-90% of confirmed cases
• MRI — essential to identify space-occupying lesion causing compression (changes treatment approach significantly)
• Ultrasound — real-time visualization of nerve, surrounding structures, and guided injection
• X-ray — identifies bony causes (heel spur, ankle arthritis)

Treatment Options

Conservative Treatment (First-Line)

• Custom orthotics — custom foot orthoses with medial arch support reduce pronation and decompress the tarsal tunnel; one of the most effective conservative interventions
• Activity modification — reduce prolonged standing, walking on hard surfaces, and high-impact activity during acute phase
• Anti-inflammatory medications — NSAIDs (ibuprofen, naproxen) to reduce swelling around the nerve
• Supportive footwear — wide toe box, firm arch support, low heel; avoid completely flat shoes that increase pronation
• Physical therapy — nerve gliding exercises to reduce adhesions; calf and ankle stretching

Corticosteroid Injection

An ultrasound-guided corticosteroid injection into the tarsal tunnel reduces nerve inflammation and swelling. It provides significant temporary relief in 50-70% of patients and can help confirm the diagnosis. Response duration varies — some patients need repeat injections every few months.

MLS Laser Therapy

MLS laser therapy reduces perineural inflammation and promotes nerve healing through photobiomodulation. It is particularly valuable for patients wanting to avoid injections or who have had inadequate relief from corticosteroids.

Surgical Tarsal Tunnel Release

Surgery is considered when conservative treatment over 3-6 months has failed to provide adequate relief. The procedure involves releasing the flexor retinaculum to decompress the tibial nerve and its branches. When a space-occupying lesion is identified, its removal is performed simultaneously.

• Success rate: 75-85% for appropriately selected patients
• Best outcomes: younger patients, shorter symptom duration, identifiable compressive lesion
• Recovery: protected weight-bearing for 2-4 weeks; return to normal activity at 6-8 weeks

If you have burning or tingling pain in your foot that hasn’t responded to plantar fasciitis treatment, schedule an evaluation — TTS requires a different treatment approach entirely.

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Related Patient Guides

• Tarsal Tunnel Syndrome Treatment Michigan
• Neuropathy in Feet: Relief Guide
• Morton’s Neuroma: Symptoms & Treatment
• The Complete Guide to Custom Orthotics
• MLS Laser Therapy for Nerve Pain
• Peripheral Neuropathy in the Feet: Symptoms & Care

Medical References & Sources

• American Podiatric Medical Association — Patient Education
• American Orthopaedic Foot & Ankle Society — Foot Conditions