Overview
This is a painful condition affecting a small nerve in the foot. It occurs when the five long bones that run the length of the foot get pushed together, pinching the nerve in between. This friction on the nerve causes it to thicken and inflame causing pain. The condition gets its name from an American surgeon, George Morton.
Causes
Although in many areas of medicine, it?s easy to pinpoint the exact source of a problem (the way a specific germ causes a certain illness with recognizable symptoms), neuromas are harder to categorize. While there isn?t really one exact cause, podiatric physicians tend to agree that a neuroma can occur in response to the irritation of a nerve by one or more factors. Abnormality in foot function or foot mechanics: In other words, a foot that doesn?t move the way science thinks it should. In general, this means a pronated foot (one with an excessive rolling motion when the patient is walking, running or doing any kind of activity), because it causes excessive strain on the nerve. If you are not certain whether or not this is a problem for you, ask your podiatric physician, who will be able to examine your feet, as well as the wear pattern on your shoe, and give you an answer. Foot mechanics, and problems with them, tend to run in families, so if you know that a relative has had foot pain similar to yours, be sure to mention it.
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 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 or by wearing high heels or shoes with a narrow toe box.
Diagnosis
Patients with classic Morton?s neuroma symptoms will have pain with pressure at the base of the involved toes (either between the 2nd and 3rd toes, or between the 3rd and 4th toes). In addition, squeezing the front of the foot together can exacerbate symptoms. As well, they may have numbness on the sides of one toe and the adjacent toe as this corresponds with the distribution of the involved nerve.
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
Surgery to excise the neuroma is usually performed under general anaesthetic in a day surgery facility. After surgery you will have to keep your foot dry for two weeks. Generally neuroma surgery allows for early weight bearing and protection in some type of post op shoe gear. Some neuromas may reoccur, but this is rare. Most studies on patient satisfaction after neuroma surgery show approximately 90% reduction of pain and about 85% of all patients rated the overall satisfaction with the results as excellent or good.
Prevention
To help reduce your chance of developing Morton’s neuroma avoid wearing tight and/or high-heeled shoes. Maintain or achieve ideal body weight. If you play sports, wear roomy, properly fitting athletic footwear.