Morton neuroma (interdigital neuroma), first described in 1876, is a perineural fibrosis and nerve degeneration of the common digital nerve. Morton neuroma, or Morton’s neuroma, is not a true neuroma, although it results in neuropathic pain in the distribution of the interdigital nerve secondary to repetitive irritation of the nerve. The most frequent location is between the third and fourth metatarsals (third webspace). Other, less common locations are between the second and third metatarsals (second webspace) and, rarely, between the first and second (first webspace) or fourth and fifth (fourth webspace) metatarsals.
Anything that causes compression or irritation of the nerve can lead to the development of a neuroma. One of the most common causes comes from wearing shoes that have a tapered toe box, or high-heeled shoes that cause the toes to be forced into the toe box and overload pressure onto the forefoot. An injury or trauma to the forefoot may also lead to a neuroma. People at a higher risk of developing a Neuroma include people with certain foot deformities, such as bunions or hammertoes. Certain foot types, such as flat feet (Pronation) More flexible feet, and woman after pregnancy.
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.
A doctor can usually identify Morton’s neuroma during a physical exam. He or she will squeeze or press on the bottom of your foot or squeeze your toes together to see if it hurts. Your doctor may also order an X-ray of your foot to make sure nothing else is causing the pain.
Non Surgical Treatment
In most cases, initial treatment for this condition consists of padding and taping to disperse weight away from the neuroma. If the patient has flatfeet, an arch support is incorporated into footwear. The patient is instructed to wear shoes with wide toe boxes and avoid shoes with high heels. An injection of local anesthetic to relieve pain and a corticosteroid to reduce inflammation may be administered. The patient is advised to return in a week or 2 to monitor progress. If the pain has been relieved, the neuroma is probably small and caused by the structure of the patient’s foot and the type of shoes the patient wears. It can be relieved by a custom-fitted orthotic that helps maintain the foot in a better position. Another type of therapy that may be used is alcohol sclerosing injections. In this treatment, the doctor injects a small amount of alcohol in the area of the neuroma area to help harden (sclerose) the nerve and relieve the pain. Injections are given every 7-10 days and, in many cases, 4-7 injections are needed for maximum relief. Please ask your physician for more information regarding this type of treatment.
When medications or other treatments do not work, podiatric surgery may be required. The most common surgical procedure for treating Morton?s neuroma is a neurectomy, in which part of the nerve tissue is removed. Although this procedure effectively removes the original neuroma, sometimes scar tissue known as a stump neuroma forms at the site of the incision. This may result in tingling, numbness, or pain following surgery. Surgery is effective in relieving or reducing symptoms for Morton?s neuroma patients in about 75% to 85% of all cases. Occasionally, minimally invasive radio frequency ablation is also used to treat Morton’s neuroma.