FAMILY MEDICINE® COLUMN

By Martha A. Simpson, D.O., M.B.A.
Associate Professor of Family Medicine
Ohio University College of Osteopathic Medicine

READER’S LEG PAIN COULD HAVE MANY DIFFERENT CAUSES

Question: I have pain in my legs so bad that it wakes me at night. I also have pain during the day. My both of my legs swell just a little bit when I'm up. What could be the cause of my leg pain?

Answer: The legs are complicated structures. The bones -- and the ligaments that help support them -- form the basic framework of the legs. The leg muscles fill out most of the contour of the legs, and their contraction produces movement of the leg bones.

All of the leg structures depend on a constant and well-regulated circulation through the arteries, veins and lymphatic system. The nervous system coordinates the actions of all these other areas. However, because a problem in any of them can cause pain in the leg, it's often not easy identifying the specific cause of a person's leg pain. In your case, three possibilities seem most likely: a circulation problem, a nerve problem, or muscle cramps.

First, let's look at how poor circulation can cause leg pain. When swelling is present, as in your condition, the problem is often an inadequate return of the blood to the heart by the veins. This inadequate return blood flow can also cause the kind of pain you describe. The pain is often brought on with exercise, but it takes a fairly long rest with the legs elevated to get relief.

Another circulation problem that causes leg pain involves an inadequate supply of blood as it passes through the arteries on the way to nourish the body's various cells. This often produces a condition -- called intermittent claudication -- that results in exercise-induced leg pain. However, unlike in your case, the pain usually subsides after a relatively brief rest.

Second, leg pain can be a sign of irritation to the nervous system. The irritation to the nerves can be caused by a generalized body-wide illness such as diabetes, or by damage to the nervous system from conditions such as spinal canal stenosis, herniated disk, or multiple sclerosis. Some of these illnesses -- like circulatory problems -- can cause swelling in the legs.

Third, I think it's possible that cramps might be the culprit. A "charley horse" is a good example of the pain caused by a muscle cramp. During a normal muscle contraction some of the muscle fibers are contracting, but not all. During a muscle cramp, most of the muscle fibers contract simultaneously, causing stress on the muscle and its attachment to the bone. It is this stress -- which can be quite severe -- that actually causes the pain we feel during a leg cramp.

Leg cramps can occur during strenuous exercise, but they happen more often at night after hard activity during the day. They can also be brought on by a disturbance in the body's balance of salts, called electrolytes. This happens most often as a complication of taking medication for high blood pressure or for heart problems.

Bone problems are also possible sources of leg pain. Stress fractures, a hair-line break in the bone produced without a known injury, bruises to the bone, and malignant and non-malignant tumors all cause pain. Bone pain can be dull and aching or it can be sharp and stabbing. When swelling occurs with these problems, it is usually confined to the area of injured bone, and it usually occurs in one leg only.

Each of these conditions has a different treatment. In fact, each has several different treatments. You will need to see your family physician to figure out the cause of your leg pain. He or she may refer you to another specialist as well.

Family Medicine® is a weekly column. To submit questions, write to Martha A. Simpson, D.O., M.B.A., Ohio University College of Osteopathic Medicine, P.O. Box 110, Athens, Ohio 45701, or via e-mail to readerquestions@familymedicinenews.org. Medical information in this column is provided as an educational service only. It does not replace the judgment of your personal physician, who should be relied on to diagnose and recommend treatment for any medical conditions. Past columns are available online at www.familymedicinenews.org.