If you sometimes feel that you are “walking on a marble,” and you have persistent pain in the ball of your foot, you may have a condition called Morton’s neuroma. A neuroma is a benign tumor of a nerve. Morton’s neuroma is not actually a tumor, but a thickening of the tissue that surrounds the digital nerve leading to the toes. Morton’s neuroma occurs as the nerve passes under the ligament connecting the toe bones (metatarsals) in the forefoot. Morton’s neuroma most frequently develops between the third and fourth toes, usually in response to irritation, trauma or excessive pressure. The incidence of Morton’s neuroma is 8 to 10 times greater in women than in men.
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 include: pain on weight bearing, frequently after only a short time. The nature of the pain varies widely among individuals. Some people experience shooting pain affecting the contiguous halves of two toes. Others describe a feeling like having a pebble in their shoe or walking on razor blades. Burning, numbness, and paresthesia may also be experienced. Morton’s neuroma lesions have been found using MRI in patients without symptoms.
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
Initial treatment for Morton?s Neuroma may include non-prescription anti-inflammatory medications to reduce pain and swelling. These may consist of standard analgesics such as aspirin and ibuprofen (Advil, Motrin, others). Massaging the painful region three times daily with ice. Change of footwear. Avoid tight shoes, high heels or any footwear that seems to irritate the condition. Low heeled shoes with softer soles are preferable. Arch supports and foot pads to help reduce pressure on the nerve. In some cases, a physician may prescribe a customized shoe insert, molded to fit the contours of the patient?s foot. Reducing activities causing stress to the foot, including jogging, dancing, aerobic activity or any high impact movements of the foot. Injections of a corticosteroid medication to reduce the swelling and inflammation of the nerve and reduce pain. Occasionally other substances may be injected in order to ?ablate? the Neuroma. (The overuse of injected steroids is to be avoided however, as side effects, including weight gain and high blood pressure can result.)
Operative treatment of Morton?s neuroma should be entertained only after failure of nonoperative management. Standard operative treatment involves identifying the nerve and cutting (resecting) it proximal to the point where it is irritate/injured. This is usually done through an incision on the top (dorsal) aspect of the foot, although in rare instances, an incision on the sole (plantar) aspect of the foot maybe used. An incision on the sole of the foot works very well, unless an excessive scar forms in which case it can be problematic. Some physicians will attempt to treat Morton?s neuroma by releasing the intermetatarsal ligament and freeing the nerve of local scar tissue. This may also be beneficial.
The best way to prevent a neuroma is by avoiding the things that cause them. Review your risk factors. If relatives have had similar problems, or if you know that you pronate or have any problem with the mechanics of your foot, talk with a podiatric physician about the correct types of shoes and/or orthoses for you. If you are not sure whether you have such a problem, the podiatric professional can analyze your foot, your stride and the wear pattern of your shoes, and give you an honest evaluation. Remember, though, that sometimes neuromas, like other conditions, can develop for no discernible reason. With this in mind, be good to your feet, and be aware of any changes or problems. Don?t wait to report them.