Nenita Ciborowski

The Globe's Best Foot Blog

What Causes Mortons Neuroma

Overview

plantar neuromaMorton's neuroma is the common name given to the nerve irritation that is found in the ball of the foot that may or may not be accompanied by an inter-metatarsal bursae (a bursa-neuromal complex). It is often associated with inflammation or degeneration and often occurs with constant pressure or irritation of the nerve from the surrounding bony structures or local bursas (fluid filled sacs). Morton's Neuroma can cause symptoms such as a sharp pain, burning even a lack of feeling in the ball of the foot and associated toes.

Causes

Morton's neuroma is an inflammation caused by a buildup of fibrous tissue on the outer coating of nerves. This fibrous buildup is a reaction to the irritation resulting from nearby bones and ligaments rubbing against the nerves. Irritation can be caused by Wearing shoes that are too tight. Wearing shoes that place the foot in an awkward position, such as high heels. A foot that is mechanically unstable. Repetitive trauma to the foot such as from sports activities like tennis, basketball, and running. Trauma to the foot caused by an injury such as a sprain or fracture. It is unusual for more than one Morton's neuroma to occur on one foot at the same time. It is rare for Morton's neuroma to occur on both feet at the same time.

Symptoms

Patients with a Morton's neuroma typically experience a sharp, shooting or burning pain, usually at the base of the forefoot or toes, which radiates into the two affected toes. Sometimes the pain may also radiate into the foot. The pain is often associated with the presence of pins and needles and numbness.

Diagnosis

To confirm the diagnosis, your doctor will examine your feet. He or she will look for areas of tenderness, swelling, calluses, numbness, muscle weakness and limited motion. To check for a Morton's neuroma, your doctor will squeeze the sides of your foot. Squeezing should compress the neuroma and trigger your typical pain. In some cases, your doctor will find numbness in the webbed area between the affected toes. Pain in two or more locations on one foot, such as between both the second and third toes and the third and fourth toes, more likely indicates that the toe joints are inflamed rather than a Morton' neuroma.

Non Surgical Treatment

Once a diagnosis is obtained, it is essential to begin treatment immediately. Your podiatric physician will advise you on the most effective means. If caught early enough, good foot care, shoes that fit properly, and/or orthoses may eliminate the need for any further intervention. Other conservative measures might include oral non-steroidal anti-inflammatory medication (NSAIDS), physical therapy, ultrasound or other non-invasive measures. If that doesn?t work, your podiatric physician might use injectable steroids, and/or a local anesthetic around the neuroma to reduce inflammation and pain. Many patients report relief after these measures are taken.Morton neuroma

Surgical Treatment

Surgery for Morton's neuroma is usually a treatment of last resort. It may be recommended if you have severe pain in your foot or if non-surgical treatments haven't worked. Surgery is usually carried out under local anaesthetic, on an outpatient basis, which means you won't need to stay in hospital overnight. The operation can take up to 30 minutes. The surgeon will make a small incision, either on the top of your foot or on the sole. They may try to increase the space around the nerve (nerve decompression) by removing some of the surrounding tissue, or they may remove the nerve completely (nerve resection). If the nerve is removed, the area between your toes may be permanently numb. After the procedure you'll need to wear a special protective shoe until the affected area has healed sufficiently to wear normal footwear. It can take up to four weeks to make a full recovery. Most people (about 75%) who have surgery to treat Morton's neuroma have positive results and their painful symptoms are relieved.