FAMILY MEDICINE® COLUMN

By John C. Wolf, D.O.Associate Professor of Family Medicine Ohio University College of Osteopathic Medicine

SUGAR INJECTIONS FOR KNEE PAIN OFTEN NOT A BIG HELP

Question: I have been having a problem with Osgood-Schlatter disease since I played football in high school. My two brothers and I all have this problem. Along with this, two of us have suffered fractured kneecaps. Although they have healed, we sometimes continue to experience pain in our knees after exercising or even just from squatting. I recently heard of a treatment in which sugar is injected into the knees to heal Osgood-Schlatter, and I wonder is this is safe and if it would be effective on the knee pains I have now?

Answer: Let me briefly go through a primer on knee structure and function before I talk about treatment for your Osgood-Schlatter disorder. Four major bones -- the upper leg bone (the femur), the lower leg bones (the tibia and fibula), and the kneecap (patella) form the knee joint. The knee is straightened mainly by the pull of a group of four powerful muscles that are arranged on the front surface of the upper leg. These muscles, the quadriceps femoris or "quads" for short, straighten the knee joint by the pull exerted on the tendon that attaches to the tibia just below the kneecap. Actually, the tendon doesn't directly attach there. Instead, it attaches to the kneecap, which acts as a protective and stabilizing part of the knee joint. There is then a short tendon that connects the patella with the tibia. Actually, you can accurately picture the kneecap as a bony "bump" that develops at this particular point along this quad tendon. A powerful contraction of the quads produces a great mechanical stress at the point where the patellar tendon attaches to the tibia. In about 13 percent of adolescents, this place becomes tender and inflamed. Slightly more common in boys, Osgood-Schlatter disease develops most often in the adolescent years of rapid growth, typically 11 to 18 in males and a year younger in females. This problem is more common in those individuals who are engaged in activities involving repeated running or jumping. Your development of the condition while playing high school football is quite typical.

The attachment point of the patellar tendon onto the tibia becomes tender and it often becomes enlarged, thereby forming a knot instead of the usual small bump. The condition is treated by relative rest; that is, by avoiding vigorous activity for a while and by the application of ice. Usually the condition subsides within a few weeks and the person can return to athletic endeavors.

Healing produces a strong union between the patellar tendon and the tibia, but the enlarged bump of Osgood-Schlatter disease is a permanent feature. Though the condition is healed and stable, up to 50 percent of adults still complain of occasional knee pain from the disorder. Perhaps this is what you and your brothers are experiencing. You may also be experiencing discomfort from chronic cartilage damage or arthritic changes in the knee. These problems could result from the trauma that broke your kneecap or from other recent or more remote knee injuries you received -- perhaps even those from long ago while playing football.

There have been attempts to improve a number of ligament or tendon disorders by injecting the area with sugars, salts or other chemicals that cause a mild scarring reaction. Depending upon the particular problem being treated, the results of this type of treatment can be satisfactory. However, it often isn't all that great. It would have no benefit for healed Osgood-Schlatter disease that only produces occasional discomfort. I'd suggest that you see an orthopedic surgeon to figure out why your knee hurts. Then you can talk about the benefits and risks of each possible treatment.

"Family Medicine" is a weekly column.

To submit questions, write to John C. Wolf, D.O., at Post Office Box 110, Athens, Ohio 45701.

Past columns are available online at http://www.FamilyMedicineNews.org.