Neuromas

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Numbness and burning in the feet are easily the two most miss-diagnosed and misunderstood symptoms that we see. The symptoms are generally caused by one of three things: neuromas, tarsal tunnel syndrome, or neuropathy. They can be also caused by a combination of all three. In addition, these symptoms can be caused by back injury and disease. Therefore, the most difficult part of diagnosing numbness and burning in the feet is diagnosing the cause! This can sometimes take a little time and a number of tests to differentiate the cause.

What is the problem?

The classic symptoms of a neuroma are numbness and tingling in the toes, most often the 3rd and 4th toes. On occasion there will be a sharp "shooting" pain into these toes. This pain usually occurs when shoes are being worn and some relief is obtained when the shoe is removed and the foot massaged. Patients also complain of a "full" or a "pulling" sensation in the bottom of their foot...a feeling like their sock is "bunched up" under the foot.

The forepart of the foot is made up of long bones called the metatarsal bones. These bones begin in the mid portion of the foot and end in the 'ball" of the foot. In between each of these long bones there is a nerve Figure 1. This nerve divides at a point where the toes begin and 1/2 of the nerve goes into the adjacent toes. This serves as a portion of the nerve supply to the toes. When a side view is looked at Figure 2 it is seen that the nerve is actually on the bottom of the foot and when it divides, it goes upward into the toes.

A neuroma is caused by a bruising of the covering of the nerve on the bottom or sole of the foot. This is a fatty material that surrounds the nerve normally and protects it. When injured, this covering begins to fibrose or scar and begins to enlarge Figure 3. This then "squeezes" the nerve and creates the symptoms Figure 4. Generally we are able to visualize the mass on Ultrasound, a procedure that we perform in our office.

What can be done?

Certainly we begin by treating this conservatively. We will generally inject the neuroma with a steroid preparation and pad the area. In some cases, this is all that will be necessary. Those cases where the neuroma has fibrosed over a long period of time, the only permanent solution is to remove the tumor. Because the nerve is on the bottom of the foot as we saw in figure 2, we place a small incision on the bottom of the foot directly over the neuroma Figure 5.

In this area, there are no vital structures that could be damaged and thus healing is much faster. Through this incision, the neuroma is removed and then the incision is sutured Figure 6 and 7. This a procedure that we do in the Ford Center for Foot Surgery. Following this, a comfortable shoe will need to be worn for a week or two. You can resume your normal activities except for heavy exercise which can begin in two weeks. Following the surgery, the pain that you have experienced will not be present. You will continue to have some numbness while the nerve heals back together.