What Is Tarsal Tunnel Syndrome?

Introduction

The tarsal tunnel is a narrow space in the ankle which contains several important structures, including several leg muscle tendons, the arteries and veins that supply the leg and foot with blood, and a nerve called the posterior tibial nerve, which allows you to feel sensation in your foot. The tarsal tunnel is located behind the medial malleolus, a prominent bone on the inner side of the ankle. Two other bones of the ankle, the calcaneus and talus, form each side of the tarsal tunnel. The flexor retinaculum, a structure composed of connective tissue, holds the tarsal tunnel in place and forms its roof.^1,2,3

Tarsal tunnel syndrome, also known as posterior tibial nerve neuralgia or tibial nerve dysfunction, is a rare condition among a class of conditions known as ‘entrapment neuropathies’. Like other entrapment neuropathies, tarsal tunnel syndrome occurs when the structures and nerves within it are compressed. This compression can result from certain diseases or external forces on the tarsal tunnel and can cause a loss of function in the foot and ankle. A consultation with a doctor, involving them taking your patient history and physically examining you, can be sufficient to diagnose the condition, though sometimes other tests are necessary. Management and treatment of tarsal tunnel syndrome can vary across patients, depending on the severity of one’s condition, and can be surgical or non-surgical.^1,3

Causes of tarsal tunnel syndrome

A cause of tarsal tunnel syndrome can be identified in most patients. However, the cause of the condition remains unknown in one in five patients.¹

Tarsal tunnel syndrome can occur secondary to several diseases:¹

• Tendinopathy
• Tenosynovitis
• Morton’s neuroma or perineural fibrosis
• Bone spurs or osteophytes
• Hypertrophic (enlarged) flexor retinaculum 
• Masses and lesions
• Obesity

Tarsal tunnel syndrome can also result from external forces on the tarsal tunnel:¹

• Poorly-fitting shoes
• Physical trauma 
• Surgery
• Oedema (swelling) of the lower limb

Signs and symptoms of tarsal tunnel syndrome

Tarsal tunnel syndrome can cause various signs and symptoms, which can vary across patients depending on how compressed their tarsal tunnel becomes. Symptoms include:²

• Sharp shooting pain from the ankle that radiates to the arch and base of the foot
• Numbness at the base of the foot
• Burning or tingling sensations in the foot

Uncomfortable sensations in the ankle and foot may be worsened by touching or tapping on the area. Furthermore, signs and symptoms are often worse at night, whilst standing or walking, or following physical activity. Rest may help reduce pain and other symptoms.²

Diagnosing tarsal tunnel syndrome

Several tools can be employed to diagnose tarsal tunnel syndrome, including a patient history, physical examination, and imaging techniques. These can rule out conditions that may present similarly to tarsal tunnel syndrome, including:²

• Achilles tendonitis
• Compartment syndrome
• Degeneration of structures in the ankle and foot
• Inflammation of structures in the ankle and foot
• Compression of nerves in the spinal cord
• Morton’s neuroma or perineural fibrosis
• Intermittent claudication
• Plantar fasciitis
• Polyneuropathy
• Retrocalcaneal bursitis

Patient history

A patient history can be taken during a consultation with a doctor. Here, a doctor will ask you several questions about why you are seeing them and your health in general, particularly the symptoms you have been experiencing. This provides an opportunity for you to also ask any questions that you may have.⁴

Physical examination

A doctor may inspect the foot and ankle region to check for any visible abnormalities, such as muscle weakness and abnormal foot positioning. You may be asked to move your foot in different directions to test its strength and mobility. A doctor may also palpate (touch and apply pressure to) the region of the tarsal tunnel to check for pain. You may be asked to close your eyes as a doctor taps areas of your foot to check the levels of sensation in your foot.²

Imaging techniques

Ultrasounds and magnetic resonance imaging are techniques that are useful in diagnosing tarsal tunnel syndrome as they can produce images of the tarsal tunnel, allowing any abnormalities to be seen.³ An ultrasound involves passing a probe over the ankle and creates an image using sound waves. Magnetic resonance imaging generates images using magnetic fields and radio waves whilst you lie in a tunnel-like scanner.

Electromyography

Electromyography can indicate whether nerves are compressed in the tarsal tunnel.³ This technique involves wires being attached to the skin overlying the tarsal tunnel with sticky patches called electrodes. These electrodes record the electrical activity in underlying muscles and the results of this are then analysed and interpreted by a clinician to determine whether there is any problem with related nerves.

Management and treatment of tarsal tunnel syndrome

Non-surgical

Modifying physical activity 

Physical activity, particularly strenuous sports, can worsen the pain caused by tarsal tunnel syndrome. Therefore, reducing physical activity and getting more rest can help relieve any pain you are experiencing. It is important for athletes to be aware that certain movements, such as jumping and sprinting, can trigger tarsal tunnel syndrome.^2,3,5 

Stretching

Stretching can be helpful in relieving pain caused by tarsal tunnel syndrome. In particular, stretching the calves can provide relief. A physiotherapist can help you discover specific stretches that alleviate your discomfort and pain.³

Shoes

Sometimes, poorly-fitting shoes can cause tarsal tunnel syndrome and worsen the pain associated with the condition. Therefore, in these cases, better-fitting shoes can aid in alleviating the burden of tarsal tunnel syndrome. Furthermore, orthotic footwear can help reduce compression of the tarsal tunnel, thus reducing symptoms of tarsal tunnel syndrome.³

Medication

Medication can be important in relieving pain caused by tarsal tunnel syndrome. Paracetamol and non-steroidal anti-inflammatory drugs can help alleviate pain. Furthermore, for pain specifically associated with the nerves, drugs, such as gabapentin, pregabalin, and tricyclic antidepressants, can be of help.³

Surgery

Your doctor may recommend surgery if the non-surgical management and treatment approaches listed above are unsuccessful in alleviating or resolving your tarsal tunnel syndrome. Typically, surgery involves releasing the flexor retinaculum, which forms the roof of the tarsal tunnel, from one of the areas that it is attached to, reducing the extent to which the tarsal tunnel is compressed. The success of surgery varies from patient to patient, but it is generally more successful in younger patients, patients who are diagnosed early, when the cause of a patient’s tarsal tunnel syndrome is known, and in patients without any existing ankle conditions or diseases.³

Summary

Tarsal tunnel syndrome is a rare condition in a class of conditions called entrapment neuropathies. It is characterised by compression of nerves in the tarsal tunnel, resulting in a loss of function in the foot and ankle. This compression can result from certain diseases or external forces on the tarsal tunnel. Diagnosis is often reached through a consultation with a doctor, where the doctor gets an overview of your medical history and physically examines you. However, imaging techniques may also be used to confirm a diagnosis of tarsal tunnel syndrome. How much the tarsal tunnel is compressed and the extent to which there is a loss of function in the foot and ankle can vary across patients, and, therefore, some patients may benefit from surgery, whilst other patients’ conditions can be addressed through non-surgical measures.

FAQs

Is surgery always necessary for tarsal tunnel syndrome?

Surgery is not always necessary for treating tarsal tunnel syndrome. In fact, surgery is typically only considered if non-surgical measures have failed to be effective.³

How long does it take to recover from tarsal tunnel syndrome?

Recovery time for tarsal tunnel syndrome varies across patients, with the success of different management and treatment plans varying from patient to patient. Some patients can be successfully managed and treated with non-surgical measures, whereas some patients may require surgery.³

Are there any self-care measures or exercises that can help alleviate the symptoms of tarsal tunnel syndrome?

Some self-care measures or exercises can help alleviate the symptoms of tarsal tunnel syndrome. Firstly, modifying your physical activity can help your condition, as tarsal tunnel syndrome can result from or be worsened by physical activity, particularly that which is more vigorous, such as jumping and sprinting. Therefore, it is important to rest, particularly if you are an athlete. Secondly, stretching, such as stretching of the calves, can be a helpful exercise in alleviating pain. A physiotherapist can help you discover stretches that may be helpful for you. Thirdly, ensuring that your shoes are not too tight can help reduce compression on the tarsal tunnel, alleviating the physical impact tarsal tunnel syndrome may have on you.³

Can tarsal tunnel syndrome recur after treatment?

Tarsal tunnel syndrome can recur after treatment as therapy may not adequately reduce the compression in the tarsal tunnel. 10 to 20 per cent of patients who undergo surgery will have recurrent tarsal tunnel syndrome. If said recurrence occurs, a second surgery can be done to resolve the condition.⁶