Tarsal tunnel syndrome

Anatomy: What is the tarsal tunnel?

The tarsal tunnel is a narrow passage on the inside of the ankle, directly behind the medial malleolus. A tight band (flexor retinaculum/ligament laciniatum) covers this canal. Tendons, vessels and the tibial nerve run underneath, which is divided into the medial and lateral plantar nerves as well as calcaneal branches for the heel.

• Contents of the tarsal tunnel: Tendons of M. tibialis posterior, M. flexor digitorum longus, M. flexor hallucis longus
• Vessels: A./V. tibialis posterior
• Nerves: Tibial nerve with its plantar branches and calcaneal branch
• Tight spaces: little reserve – swelling or increases in volume easily lead to compression

The symptoms arise from pressure on the nerve, often increased by stress, prolonged standing/walking or by severe pronation (folding) of the foot.

Causes and risk factors

Tarsal tunnel syndrome is usually due to a multifactorial interplay of mechanical tightness, incorrect loading and tissue swelling. Common triggers are:

• Foot misalignments: arched arches/pes planovalgus, tibialis posterior insufficiency
• Overload: long periods of standing/walking, running increases, hard floors
• Post-traumatic: Ankle joint distortions with scarring or a tendency to swell
• Space-occupying lesions: ganglion, lipoma, varices, synovitis
• Systemic factors: diabetes, hypothyroid metabolism, pregnancy (edema), inflammatory rheumatic diseases
• Shoes: very tight, tight or poorly supportive shoes

It is not uncommon for several factors to work together - e.g. B. functional overpronation with accompanying tendonitis and slight soft tissue swelling, which further narrows the already narrow canal.

Symptoms: How do you recognize tarsal tunnel syndrome?

• Burning, stabbing or pressing pain on the sole of the foot, often emphasized medially
• Paresthesias: tingling, pins and needles, electrifying feeling
• Areas of numbness on the heel, medial edge of the foot and/or forefoot (depending on the nerve branches affected)
• Increase in symptoms when standing/walking for long periods of time; Relief at rest, when elevated or changing shoes
• Pain at night, occasional leg cramps
• Rare motor deficits: Weakness of the short foot muscles with misalignment of the toes due to long-term compression

A local feeling of pressure or a positive Tinel sign (electricity when tapping behind the inner ankle) supports the diagnosis. The dorsiflexion/eversion test (tightening the foot and turning it outwards) can cause discomfort.

Diagnostics in orthopedics

Diagnosis is based on history, clinical examination and targeted imaging. Not every examination is necessary in every case; it is planned individually.

It is also important to distinguish it from other causes of sole pain and numbness, as the therapeutic approaches vary.

Conservative therapy: The standard route first

In most cases, we start with a structured conservative treatment plan lasting 6-12 weeks. The aim is to relieve the nerve, calm inflammation and correct triggering factors.

• Load control: temporarily reduce running and standing times, gradually increase the amount of training.
• Shoe advice: enough space in the forefoot, stable heel cap, good cushioning; Avoiding hard edges on the inner ankle.
• Insoles/Orthoses: medial longitudinal arch support to reduce overpronation; If necessary, soft heel bedding.
• Physiotherapy: Strengthening the internal foot muscles and the tibialis posterior muscle, mobilization of the ankle joint, neurodynamic nerve mobilization (nerve gliding exercises).
• Short-term anti-inflammatory drugs (NSAIDs) to control pain and inflammation - after weighing the benefits and risks.
• Cooling in acute phases, elevation after exercise.
• If irritation is severe: temporary immobilization in a stable shoe/walker; close follow-up monitoring.

Relevant concomitant diseases (e.g. diabetes, hypothyroidism, rheumatic diseases) are included in the treatment. Targeted weight reduction can reduce the load on the foot.

Targeted infiltrations: When can they help?

If pain and paresthesia persist despite consistent basic therapy, ultrasound-guided perineural infiltration (e.g. with local anesthetic, possibly low-dose cortisone) can be considered. The aim is to reduce inflammation in the short term and relax the surrounding structures in order to make training and everyday stress easier.

• Advantages: image-guided precision, often rapid symptom relief, diagnostic significance (is compression pain nerve-related?).
• Limits: Effect often limited in time; Causal misalignments or space-occupying lesions are not eliminated.
• Risks: temporary changes in sensation, rarely nerve irritation, infection, bruising; Use cortisone near tendons with caution.

The indication is cautious and individual. Regenerative procedures outside the guidelines will only be considered after transparent information and with clear justification.

Surgical therapy: Decompression if there is a clear indication

Surgery is considered if conservative measures are not sufficient after an appropriate period of time, there is a confirmed mechanical cause (e.g. ganglion, varices, bony narrowing), or if neurological deficits worsen.

• Procedure: Splitting the flexor retinaculum (decompression), neurolysis of the tibial nerve and - depending on the findings - the plantar canals; Removal of masses.
• Anesthesia/setting: usually in regional or general anesthesia, short-term inpatient or outpatient depending on the initial situation.
• Follow-up treatment: elevation, wound checks, early functional mobilization in protective shoes; Start nerve mobilization/physiotherapy after medical clearance.
• Ability to work/sport: depending on activity; Office 2-3 weeks, physically demanding 4-6+ weeks; Exercise can often be increased after 8-12 weeks.

Possible complications - rare, but to be taken into account: wound healing disorders, scarring problems/neuralgia, persistent sensory disorders, thrombosis, incomplete reduction of symptoms. Realistic expectation management is crucial.

Course and prognosis

Many patients benefit from conservative treatment within 6-12 weeks, especially if triggering factors (overpronation, footwear, loading errors) are addressed. If the nerve compression has been present for a long time, recovery may take longer.

• Favorable signs: early relief, clear triggering factors, good response to insoles/physiotherapy.
• Unfavorable signs: progressive deafness, motor deficits, pronounced masses, relevant deformity without correction.

Consistent aftercare with adjustment of the insoles and a functional exercise program prevents relapses.

Self-help and prevention

• Shoes with good support and enough space, no hard inner ankle edge.
• Training control: Increase the load slowly, plan breaks.
• Strengthening exercises for the arches and lower legs; Stretching the calf muscles.
• Use insoles consistently and check the fit regularly.
• Weight management and good blood sugar control in diabetes.
• Seek medical advice early if numbness or nighttime pain increases.

Differential diagnoses: What else is possible

Similar complaints on the heel and sole of the foot can have various causes. A careful clarification avoids incorrect treatment.

• Baxter neuropathy (inferior calcaneal nerve compression) – common in plantar heel pain
• Plantar fasciitis/heel spurs
• Tibialis posterior insufficiency with arched arches and secondary pain
• Morton's neuroma (between the metatarsals)
• Lumboradiculopathy (e.g. S1) or peripheral polyneuropathy
• Stress fracture of the calcaneus or tarsal bone
• Space-occupying lesions on the hindfoot (ganglion, varices)

When should you see a doctor?

• Increasing numbness or burning pain in the sole of the foot, especially at night
• New weakness in toe flexion or spreading
• Complaints > 2–3 weeks despite relief and suitable footwear
• After ankle injury with persistent paresthesia
• Warning signs: severe pain at rest, rapidly progressing neurology, fever or redness/swelling - please clarify promptly

Your treatment in Hamburg-Winterhude

In our orthopedic specialist practice at Dorotheenstrasse 48, 22301 Hamburg, we offer structured, evidence-based diagnostics and therapy for tarsal tunnel syndrome. The focus is on conservative procedures. If there is a clear indication, surgical options will be discussed with you and organized in a suitable setting.

Our goal is to make everyday life noticeably easier without unnecessary interventions – transparent, comprehensible and patient-centered.