A neuroma is an often painful enlargement of one of your body?s nerves. Morton?s neuroma is the name used to describe nerve enlargement in your foot, particularly enlargement of one of the nerves traveling to your toes in your forefoot. Morton?s neuromas most commonly develop in one of your intermetatarsal nerves, one of many nerve branches within your foot that originated in your spine. Morton?s neuroma is more likely to affect women than men.
The source of this pain is an enlargment of the sheath of an intermetatarsal nerve in the foot. This usually occurs in the third intermetatarsal space, the space between the third and fourth toes and metatarsals. It occurs here, at the site third intermetatarsal nerve, since this intermetatarsal nerve is the thickest being comprised of the joining of two different nerves. It also may occur in the other intermetatarsal areas, with the second interspace being the next most common location.
The primary symptoms include sharp, shooting pain, numbness or paresthesia in the forefoot and extending distally into the toes, typically in the region of the third and fourth toes. Symptoms are aggravated with narrow toe box shoes or those with high heels. There is usually a reduction of symptoms when walking barefoot or wearing shoes with an appropriately wide toe box. Symptoms are also aggravated with shoes that are tied too tight.
Morton?s neuroma can be identified during a physical exam, after pressing on the bottom of the foot. This maneuver usually reproduces the patient?s pain. MRI and ultrasound are imaging studiesthat can demonstrate the presence of the neuroma. An x-ray may also be ordered to make sure no other issues exist in the foot. A local anesthetic injection along the neuroma may temporarily abolish the pain, and help confirm the diagnosis.
Non Surgical Treatment
If symptoms are severe or persistent and self-help measures did not help, the doctor may recommend corticosteroid injections, a steroid medication that reduces inflammation and pain is injected into the area of the neuroma. Only a limited number of injections are advised, otherwise the risk of undesirable side effects increases, including hypertension (high blood pressure) and weight gain. Alcohol sclerosing injections, studies have shown that alcohol injections reduce the size of Morton's neuromas as well as alleviating pain. This is a fairly new therapy and may not be available everywhere. The doctor injects alcohol in the area of the neuroma to help sclerose (harden) the nerve and relieve pain. Injections are typically administered every 7 to 10 days. For maximum relief 4 to 7 injections are usually needed.
Surgical treatment has provided relief in some cases while poor results and surgical complications have resulted in other cases. It is believed that ligament weakness, as opposed to the pinching of nerves in the foot, may be to blame for recurrent pain in these situations. For reasons which are not fully understood, the incidence of Morton?s Neuroma is 8 to 10 times greater in women than in men.