Morton's neuroma

What is Morton's neuroma?

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 burning pain, numbness, tingling and other abnormal sensations in the toes. A Morton's neuroma also is called an interdigital neuroma, intermetatarsal neuroma or a forefoot neuroma.

A Morton's neuroma usually develops between the third and fourth toes. Less commonly, it develops 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. This style of shoe tends to shift the bones of the feet into an abnormal position, which increases the risk that a neuroma will form. Being overweight also increases the risk of a Morton's neuroma.

Symptoms of Morton's neuroma

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 tips 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 your shoes, flexing your toes and rubbing your feet. Symptoms may be aggravated by standing for prolonged periods, high impact activities (such as running), or by wearing high heels or shoes with a narrow toe box.

Diagnosisng Morton's neuroma

Your doctor will suspect that you have a Morton's neuroma based on the nature and location of your foot pain. He or she may ask questions about your shoes — what 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 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 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's neuroma.

Based on the physical examination, your doctor usually can diagnose a Morton's neuroma without additional testing. A foot X-ray may be ordered to make sure that there isn't a stress fracture, but it will not show the actual neuroma. If the diagnosis is in doubt, your doctor may recommend an ultrasound or magnetic resonance imaging (MRI) of the foot.

Expected duration of Morton's neuroma

A Morton's neuroma will not disappear on its own. Usually, the symptoms will come and go, depending on the type of shoes you wear and how much time you spend on your feet. Sometimes, the symptoms will go away completely.

Preventing Morton's neuroma

It is not always possible to prevent a Morton's neuroma. However, you probably can reduce your risk by wearing comfortable shoes that have low heels, plenty of toe space and good arch support.

Treating Morton's neuroma

If your Morton's neuroma is painful, initial treatment is generally conservative (non-surgical), including:

• adjustments in activities to avoid impact or pressure on the neuroma
• making sure your shoes have low heels, ample space for the toes and good arch support
• shoe inserts (orthotics) and/or padding to help correct any mechanical imbalance in the foot and to take pressure off the neuroma

• anti-inflammatory treatments, including the application of ice or taking anti-inflammatory medications (such as ibuprofen or naproxen)
• one or more injections of anesthetic and corticosteroid medications into the affected area.

Other conservative treatments, such as topical capsaicin, shockwave therapy, or injections of botulinum toxin (Botox) may be helpful but are not well studied.

It can take six months or more for conservative treatment to provide significant benefit. If pain continues, your doctor may recommend surgery to remove the neuroma or to widen the space through which the affected nerve travels. These types of surgery are often performed under local anesthesia. If your doctor removes a portion of the affected nerve along with the neuroma, you may develop permanent numbness between the toes.

When to call a professional

Make an appointment to see a health care professional if you have symptoms of a Morton's neuroma that do not improve when you wear comfortable, wide shoes.

Prognosis

More than 80% of people with a Morton's neuroma will respond to conservative treatment. For the minority of people who have persistent, disabling symptoms, surgery may be an option.

Additional info

National Institute of Arthritis and Musculoskeletal and Skin Diseases
National Institutes of Health
www.niams.nih.gov

American Podiatric Medical Association (APMA)
www.apma.org

American Orthopaedic Foot & Ankle Society
www.footdocs.org

American Academy of Podiatric Sports Medicine
www.aapsm.org

American College of Foot and Ankle Surgeons
www.acfas.org