Causes of Tarsal Tunnel Syndrome
Tarsal Tunnel Syndrome has many possible 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 close up. A bone chip in the area of the medial malleolus may also become lodged in the tarsal tunnel, causing an impingement upon the nerve.