Tarsal tunnel syndrome, also called tibial nerve dysfunction, is an uncommon form of misfiring peripheral nerves in the foot. Peripheral nerves are the nerves that carry signals from the brain and spinal cord to the other parts of the body. The tibial nerve is the peripheral nerve in the leg responsible for sensation and movement of the foot and calf muscles. In tarsal tunnel syndrome, the tibial nerve is damaged, causing problems with movement and feeling in the foot of the affected leg.
Common causes of tarsal tunnel syndrome involve pressure or an injury. Direct pressure on the tibial nerve for an extended period of time, sometimes caused by other body structures close by or near the knee, or trauma to the tibial nerve can result in tarsal tunnel syndrome. Diseases that damage nerves, including diabetes, may cause tarsal tunnel syndrome. However, tarsal tunnel syndrome can appear without an obvious cause in some cases.
Feeling different sensations in the foot at different times is a common symptom of tarsal tunnel syndrome. An afflicted person may experience pain, tingling, burning or other unusual sensations in the foot of affected leg, with primary problems occurring on the bottom of the foot. The foot muscles, toes and ankle become weaker, and curling toes or flexing the foot becomes difficult. If the condition worsens, the person may develop infections and ulcers on the affected foot because of the lack of sensation. The affected foot can become permanently deformed, and sensation loss, particularly in the toes, is sometimes permanent.
A physical exam of the leg can help identify the presence of tarsal tunnel syndrome. Medical tests, such as a nerve biopsy, are also used to diagnose the condition.
Occasionally, a person with tarsal tunnel syndrome can recover without specific treatment, but over the counter pain medication is still used to reduce the discomfort associated with the condition. Treatments for more severe tarsal tunnel syndrome focus on regaining sensation and strength in the affected toes and foot. Patients may receive physical therapy and prescription painkillers if the pain isn't managed by over the counter pain relievers. A surgery designed to lessen pressure on the tibial nerve can help in some cases. The surgeon enlarges the patient's tarsal tunnel, a ligament and bone structure in the foot that the tibial nerve passes through, relieving some of the pressure on the tibial nerve.