What is Tarsal Tunnel Syndrome (TTS)?

Discover the causes behind Tarsal Tunnel Syndrome, anatomy involved, plus correct treatment and prevention strategies.

by Brad Walker | Updated June 22, 2025

What is Tarsal Tunnel Syndrome?

Tarsal Tunnel Syndrome is a compression of the nerve inside the tunnel. It is less common than its counterpart in the wrist (Carpal Tunnel Syndrome), and is sometimes simply wrapped into the foot neuropathy diagnosis. The pressure can come from injuries resulting in deformities, inflammation of the protective sheath, tumors, or other impingements on the nerve. The compression on the nerve interferes with the signals sent through the nerve, causing pain and other neuropathy in the foot.

Anatomy Involved

The ankle is formed by the tibia, fibula and talus. The medial malleolus of the tibia and the flexor retinaculum form the walls of the Tarsal Tunnel. The tibial nerve passes through the tunnel into the foot. The tunnel also houses the tendons, veins and arteries that run down into the foot on the medial (inner) side. The bones, ligaments and tendons in the foot innervated by the tibial nerve are also involved in this condition.

The posterior tibial nerve runs down from the leg and behind the medial malleolus (the bump on the inside of the ankle), down into the foot. This nerve is protected by a fibrous sheath, called the flexor retinaculum. The flexor retinaculum, along with the bones of the ankle, forms a tunnel for this nerve (and tendons, arteries, veins) that runs through the foot. The ligament over the tunnel is meant to protect the components underneath, but if it becomes inflamed or a foreign body obstructs the tunnel, then it can become part of the problem.

What Causes Tarsal Tunnel Syndrome?

Tarsal Tunnel Syndrome has many potential causes, and in some cases, doctors cannot pinpoint the exact cause. People with flatfeet may develop this condition due to the strain placed on the structures of the feet and a change in the course of the nerves and tendons running into the feet. This could cause pressure on the tibial nerve.

A cyst or tumor in the area may also produce pressure on the nerve. Other abnormalities in the area that may cause this condition include varicose veins, a swollen tendon, or a bone spur.

Systemic disease processes, such as rheumatoid arthritis or diabetes, may also cause, or increase the likelihood of this condition. The inflammation of the joint caused by arthritis will decrease the space available for the nerve, thereby increasing pressure. The veins and arteries passing through may become enlarged due to higher glucose content in diabetics, also causing more pressure on the nerve. Individuals that are overweight or obese may be prone to this condition due to excessive pressure on the posterior tibial nerve.

Injury to the ankle, due to swelling in and around the joint, may also cause pressure on the tibial nerve. Fractures or dislocations may cause the tunnel to shift slightly, or narrow. A bone chip around the medial malleolus may also become lodged in the tarsal tunnel, causing an impingement upon the nerve.

Signs and Symptoms

The most common symptom of this condition is pain, burning, or tingling along the inside of the ankle and down into the foot. The pain can vary from prickly points in the foot to severe burning pain along the entire foot and ankle area. The pain generally gets worse with activity, especially prolonged walking or standing and improves with rest.

Pain upon palpation of the nerve may also be noted. Loss of sensation may be experienced if the condition is allowed to progress. A change in gait (a limp and overpronation) may also result if not treated promptly.

The symptoms may occur suddenly, but are often made worse by extended periods of activity. The earliest signs of pain are often ignored, and the condition is allowed to progress until the nerve is compromised more severely.

Treatment

Treatment for tarsal tunnel syndrome may include:

In cases where the pain and inflammation are out of control, injections of a local anesthetic and corticosteroid may be helpful. Surgical intervention is only required in the most severe cases, or in those cases that do not respond to the non-surgical interventions. This generally involves decompressing the nerve by either releasing the ligament around it, clearing the obstruction, or repairing the structures in the tunnel.

Prevention

Prevention of tarsal tunnel syndrome starts with the knowledge of what causes it and avoiding those circumstances.