Tarsal canal syndrome: what is it, symptoms, treatment, prognosis

What is tarsal canal syndrome?

Tarsal canal syndrome - a rare condition caused by damage to the tibial nerve or its branches, usually due to compression as it travels through the tarsal canal (pinched nerve). The tarsal canal is a narrow passage bounded by bone and soft tissue that lies on the inside of the ankle. The tibial nerve (as well as some blood vessels and tendons) passes through the tarsal canal. However, the term tarsal canal syndrome is often widely applied to any pain along the tibial nerve that can be caused by a variety of causes. People with tarsal canal syndrome may experience pain, burning, or tingling along the tibial nerve.

Signs and symptoms

The specific symptoms of tarsal canal syndrome can vary from person to person. In some cases, symptoms may develop suddenly, in others gradually. Some patients may experience sharp shooting pain along the tibial nerve. This nerve branches off from the sciatic nerve and travels down the lower leg to the ankle and then to the foot. The pain can be so severe that the person is limping. Patients may experience radiating pain that is not localized in one place. In addition to or instead of pain, patients may experience numbness of the affected area, a burning sensation or tingling sensation (paresthesia) like a “pin or needle”.

In some people, symptoms may affect one point, such as the inside of the ankle. In others, symptoms affect the ankle, heel, and foot. For example, pain can spread from the ankle to the heel or even the foot, depending on which part of the nerve is affected. Less commonly, pain spreads from the ankle to the calf.

The symptoms of tarsal canal syndrome are often aggravated by activities such as standing or walking for a long time. Consequently, the pain can get worse during an active day. Symptoms usually resolve with rest. However, as the disease progressed, some patients reported pain during rest or at night when trying to sleep.

Causes and risk factors

Tarsal canal syndrome can be caused by any condition that causes pinching of the tibial nerve or its branches as it travels through the tarsal canal. Tarsal canal syndrome can be caused by a variety of conditions, including swollen tumors or inflammation, which can increase pressure in the canal. Such lesions include tumors consisting mainly of adipose tissue (lipomas), tumors consisting of nerve fibers and ganglion cells (gangliomas), and neural sheath tumors (schwannomas).

Additional conditions that can cause tarsal canal syndrome include benign bone growth in tarsal canal (exostosis), dilated (varicose) veins and synovial inflammation (proliferative synovitis). Certain injuries or injuries, such as an ankle sprain, fracture or hallux valgus, can cause inflammation and edemawhich can lead to tarsal canal syndrome. In addition, some diseases such as diabetes and arthritis can also cause inflammation and swelling, which can lead to tarsal canal syndrome.

People with severe flat feet (flat feet) are at greater risk of developing tarsal canal syndrome than the general population, because flattened, "prolapsed" arches can stretch the tibial nerve.

Affected populations

The incidence and prevalence of tarsal canal syndrome are unknown. It is believed that the disease affects men and women equally.

Symptomatic disorders

Symptoms of the following conditions may be similar to those of tarsal canal syndrome. Comparisons can be useful for differential diagnosis.

Plantar fasciitis (plantar fasciosis) is a common condition characterized by inflammation of a thick strip of tissue that runs along the bottom of the foot (plantar fascia). The plantar fascia supports the arch of the foot and acts as a shock absorber. Plantar fasciitis is a common cause of heel pain, often described as acute heel pain. The pain associated with plantar fasciitis tends to develop gradually and gets worse in the morning and may decrease during the day and after stretching. In addition, this pain is different from the shooting and tingling pain associated with tarsal canal syndrome.

Pain in the foot or ankle can cause a wide range of conditions, including diabetes (diabetic neuropathy), posterior tibial tendinosis, stress fractures, some rare disorders such as reflex sympathetic dystrophy, and certain disorders that affect nerves outside of the central nervous system (peripheral neuropathy).

Diagnostics

The diagnosis of tarsal canal syndrome is made by identifying characteristic symptoms, a detailed history of the patient, careful clinical evaluation, and various specialized tests. A specific sign that allows you to detect an irritated nerve is Tinel's symptom. During a Tinel symptom test, the doctor will tap or press on the tibial nerve. If tingling occurs in the foot or toes, this is considered a positive result and indicates tarsal canal syndrome.

Additional tests that may be performed include electromyography and magnetic resonance imaging (MRI). Electromyography is a technique that can determine the condition of muscles and nerves and reveal nerve dysfunction. MRI uses a magnetic field and radio waves to produce cross-sectional images of selected organs and tissues of the body and can be used if the suspected cause of tarsal canal syndrome is swelling, or to detect irritation nerve.

Standard treatments

Treatment for tarsal canal syndrome focuses on the specific symptoms that each person experiences. Doctors may recommend conservative treatments, which may include rest, contrast baths, non-steroidal anti-inflammatory drugs (NSAIDs) and non-rigid orthopedic products. Orthopedic devices are devices such as splints or braces that are used to protect or correct the position of the foot. In some cases, switching to looser or larger shoes to relieve tightness can relieve pain associated with tarsal canal syndrome.

Some people may benefit from local injection of certain drugs (anesthetics) to relieve pain or corticosteroids to reduce inflammation. It can also be diagnostic, as the relief caused by the injection of anesthetic around the affected nerve confirms the diagnosis. In some cases, immobilization may be helpful, such as with a plaster cast. Physical therapy may also be recommended.

Patients with tarsal canal syndrome due to flat feet can be treated with orthopedic devices designed to support or restore the natural arch of the foot.

Surgery is recommended for people with severe symptoms that do not respond to conservative treatment. The goal of the surgery is to decompress the nerve from the tarsal canal and / or remove any mass.

Forecast

The prognosis of tarsal canal syndrome is different. In patients with an identifiable etiology, due to the massive effect diagnosed early in the disease, the response is usually favorable. Patients without an established cause and who do not respond to conservative therapy usually do not tolerate surgery well. Positive Tinel's symptom is a reliable predictor of surgical treatment.

Complications

Untreated or refractory syndrome can lead to neuropathy of the posterior tibial nerve and its branches. Patients may experience constant pain. In the future, motor weakness and atrophy may develop. Postoperative complications include impaired wound healing, infection, and scarring. Surgical decompression may not relieve pain and other symptoms.