What Is Tarsal Tunnel Syndrome?
The tarsal tunnel is the canal formed between the bone on your inner ankle (medial malleolus) and a structure that runs across the inside of the ankle and foot to hold tendons down (the flexor retinaculum). The most common cause of pain in this area is compression of the major nerve that runs through the tunnel, called the posterior tibial nerve. Compression or squeezing, on this nerve, produces symptoms anywhere along the path of the nerve running from the inside of the ankle into the foot. This nerve is responsible for sensation in the bottom of your feet.Tarsal tunnel syndrome is similar to carpal tunnel syndrome, which occurs in the wrist. Both disorders arise from the compression of a nerve in a confined space.
Causes of Tarsal Tunnel Syndrome
Tarsal Tunnel Syndrome is caused by anything that produces compression or squeezing, on the posterior tibial nerve. Some causative factors may include:
- Flat feet (over-pronation) – flat feet are at risk for developing tarsal tunnel syndrome. The outward tilting of the heel that occurs with flat feet can produce tension and compression on the nerve.
- Muscular restrictions, such a tightness in the calf muscles can lead to a change in foot and ankle function and excessive pressure on the nerve.
- An enlarged or abnormal structure that occupies space within the tunnel can compress the nerve. Some examples include a varicose vein, ganglion cyst, swollen tendon, and arthritic bone spur.
- Trauma/injury such as an ankle sprain may produce inflammation and swelling in or near the tarsal tunnel, resulting in compression of the nerve.
- Systemic diseases such as diabetes or arthritis can cause swelling in the area of the tarsal tunnel, therefore compressing the nerve.
Symptoms of Tarsal Tunnel Syndrome
The most common symptoms of tarsal tunnel syndrome include:
- Pain on the medial (inside) of your ankle.
- Burning and shooting sensations in your ankle and foot.
- Numbness and tingling in the sole of the foot.
Symptoms often occur unilaterally (in one foot) and are typically felt on the inside of the ankle and/or on the bottom of the foot. Symptoms may be isolated and occur in just one spot, but they can also radiate along the sole of the foot and sometimes up into the calf.Symptoms are often brought on or aggravated by overuse of the foot, such as prolonged standing, walking, exercising, or beginning a new exercise program and are usually relieved by rest, elevation or massage.Early treatment of the symptoms is very important. Left untreated, tarsal tunnel syndrome can progress and may result in permanent nerve damage. Furthermore, because the symptoms of tarsal tunnel syndrome are similar to that of other conditions, an assessment by a podiatrist is essential so that a correct diagnosis can be made and an appropriate treatment plan can be started.
Our Treatment for Tarsal Tunnel Syndrome
A comprehensive clinical examination of the affected foot is undertaken to assess for possible causative and aggravating factors, the severity of the condition, and suitable treatment options. Diagnostic imaging such as X-rays or MRI may also be ordered.From these findings, a treatment plan is developed specifically for you. Some aspects of the treatment plan may include:
- Activity modification. An initial change to your exercise regime or daily activities may be needed to avoid the condition getting worse. The introduction of a low impact alternate activity may also be of benefit such as swimming.
- Ice. to ease pain and swelling. Do it for 20-30 minutes every 3 to 4 hours for 2 to 3 days, or until the pain is gone.
- Anti-inflammatory. Nonsteroidal anti-inflammatory drugs (NSAIDs), like ibuprofen, naproxen, or aspirin, will help with pain and swelling as per GP instructions.
- Strengthening/Isometric loading. It is important that strength is addressed for this condition so that the affected area can tolerate more load. This is done initially with isometric loading to load up the affected area in a pain-free way.
- Prolotherapy / Injection therapy. Injections of a local anaesthetic or prolotherapy can provide pain relief, and an injected corticosteroid may be useful in treating the inflammation.
- Orthotic therapy. A custom orthotic device placed in your shoe can help address possible causative factors such as flat feet, to reduce compression of the nerve.
- Adequate footwear. Supportive footwear may also be recommended.
- Taping/Bracing. Patients with flatfoot or those with severe symptoms and nerve damage may benefit from taping or bracing to reduce the pressure on the affected nerve.
- Immobilization. Restricting movement of the foot by wearing a cast is sometimes necessary to enable the nerve and surrounding tissue to heal.
Surgery for Tarsal Tunnel Syndrome
When symptoms of Tarsal Tunnel Syndrome are non-responsive to conservative treatment, surgery may be the best option.