Morton's Neuroma

What Is It?

A Morton's neuroma is a benign (noncancerous) swelling along a nerve in the foot that carries sensations from the toes. The reason the nerve starts to swell is unknown. But once swelling begins, the nearby bones and ligaments put pressure on the nerve causing more irritation and inflammation. This produces a burning pain, numbness, tingling and other abnormal sensations in the toes. A Morton's neuroma also is called an interdigital neuroma, intermetatarsal neuroma or forefoot neuroma.

Morton's neuroma usually develops between the third and fourth toes. Less commonly, it may be found between the second and third toes. Other locations are rare. It also is rare for a Morton's neuroma to develop in both feet at the same time. The condition is much more common in women than men, probably as a result of wearing high-heeled, narrow-toed shoes. High, narrow shoes tend to shift the bones of the feet into an abnormal position that increases the risk that a neuroma will form. Being overweight also increases the risk of a Morton's neuroma.

Symptoms

A Morton's neuroma usually causes burning pain, numbness or tingling at the base of the third, fourth or second toes. Pain also can spread from the ball of the foot out to the tip of the toes. In some cases, there also is the sensation of a lump, a fold of sock, or a "hot pebble" between the toes.

Typically, the pain of a Morton's neuroma is relieved temporarily by taking off the shoes, flexing the toes and rubbing the feet. Symptoms may be aggravated by standing for prolonged periods or by wearing high heels or shoes with a narrow toe box.

Diagnosis

Your doctor will suspect that you have a Morton's neuroma based on your description of the nature and location of your foot pain. He or she may ask questions about your shoes — the type of shoes you usually wear and whether these shoes have narrow toes or high heels. To rule out other causes of foot pain, your doctor may ask questions about your medical and orthopedic history, especially any history of arthritis, nerve and muscle problems, or previous injury to your foot or leg.

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 decreased range of 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 the second and third toes and between the third and fourth toes, is more likely to indicate that the toe joints are inflamed rather than a Morton' neuroma.