Pain and tingling in the foot are common in athletes and active people. While plantar fasciitis and stress fractures are well-known causes, another important condition is tarsal tunnel syndrome. This condition results from tibial nerve entrapment as it passes through a narrow space on the inside of the ankle, known as the tarsal tunnel. What is tarsal tunnel syndrome, and how do we manage it?
What Is Tarsal Tunnel Syndrome?
The tibial nerve runs down the leg and passes behind the medial malleolus (the bony bump on the inside of the ankle). At this point, it passes through a confined passage known as the tarsal tunnel, alongside tendons and blood vessels. The roof of the tennel comprises the flexor retinaculum. If the nerve becomes compressed within this tunnel, it leads to pain, tingling, and numbness in the foot – a condition known as tarsal tunnel syndrome.
There are many causes of compression of the tibial nerve in the tarsal tunnel. Examples of compression within the tunnel include tendonitis, tenosynovitis, ganglia, and varicose veins. Whereas compression from outside the tunnel consists of trauma, excessive flattened foot and tightly fitting shoes.
Symptoms of Tibial Nerve Entrapment
People with tarsal tunnel syndrome often describe:
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Burning, tingling, or shooting pain on the inside of the ankle radiating to the sole
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Numbness in the sole or toes
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Pain that gets worse with prolonged standing, running, or walking
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Night-time symptoms, sometimes waking patients from sleep
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Relief of pain when resting or taking pressure off the foot
The symptoms of tibial nerve entrapment can mimic those of plantar fasciitis, but the nerve-related burning or tingling is a key distinguishing feature.
Clinical Assessment
A sports doctor will carefully examine the ankle and foot to look for signs of nerve irritation. Clinical findings may include:
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Local tenderness behind the medial malleolus along the course of the tibial nerve
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Reproduction of symptoms when tapping the nerve (Tinel’s sign)
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Tinel’s made worse by holding the ankle in dorsiflexion and eversion
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Reduced light touch sensation in the sole
- In late cases, muscle wasting may be a feature
It is also important to exclude other causes of foot pain, such as plantar fasciitis, stress fracture, or Achilles tendinopathy.
Investigations
To confirm tarsal tunnel syndrome and exclude other causes, investigations may include:
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Ultrasound: Can show swelling of the tibial nerve or detect space-occupying lesions such as ganglion cysts.
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MRI: Provides a detailed view of soft tissue and can identify inflammation, masses, or accessory muscles pressing on the nerve. Imaging the lumbar spine can exclude referred nerve root impingement.
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Nerve conduction studies and EMG: These tests can confirm reduced tibial nerve function within the tarsal tunnel, although they may be normal in early or mild cases.
- Blood tests: On occasion, we perform blood tests to exclude inflammatory neuritis from diabetes, vitamin deficiencies, alcohol abuse or autoimmune disorders
Treatment of Tibial Nerve Entrapment
Generally, treatment success is higher when there is a recognisable cause of compression (such as a ganglion cyst). Nevertheless, treatment of tibial nerve entrapment usually begins with non-surgical options:
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Rest and activity modification: Reducing activities that aggravate symptoms, such as running on hard surfaces.
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Footwear and orthotics: Supportive shoes or insoles to reduce compression on the nerve in the tarsal tunnel.
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Physiotherapy: To improve foot and ankle biomechanics and relieve pressure on the nerve.
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Medication: Anti-inflammatory or neuropathic drugs (such as amitriptyline or duloxetine) may help
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Ultrasound-guided injection: Corticosteroid or nerve hydrodissection injections around the tibial nerve can help reduce inflammation and release pressure. A recent study found that a tarsal tunnel hydrodissection improved outcomes in 77.5% of cases and did not require a surgical release.
If symptoms persist despite conservative management, surgical decompression of the tarsal tunnel may be required. This procedure releases the nerve from tight structures and removes any lesions causing compression.
Final Word from Sportdoctorlondon about Tibial Nerve Entrapment
Tarsal tunnel syndrome is a significant cause of foot and ankle pain, particularly among runners and athletes. Because it mimics other conditions, careful clinical assessment and targeted investigations are essential for diagnosis. With the right treatment—ranging from footwear changes to injections or surgery—most patients with tibial nerve entrapment can return to full activity without long-term problems.
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