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

SORE KNEES DURING ADOLESCENCE MAY MEAN OSGOOD-SCHLATTER DISEASE

Question: My son, who is 12, has developed a painful lump on each of his knees. Our doctor said he has Osgood-Schlatter disease and that he will get over it. Would you explain this condition so I can understand it?

Answer: Osgood-Schlatter disease is a common condition that is most prevalent in boys between the ages of 9 and 15. Boys are, in fact, troubled with this condition 3 to 5 times more often than girls. Most who suffer with this condition complain of vague knee pain that is made worse with kneeling, going down stairs, running and other activities that require leg strength. A tender swelling or bump occurs below the knee cap, and putting mild pressure on the area produces pain.

To understand this disease we need to remember that all bone is a complex growing tissue. Don't think of bone as a hard, stable collection of minerals, because this is inaccurate. Bone is constantly undergoing change. In this process some minerals and cells are lost while simultaneously new growth replaces them. In an adult, the rate of "bone destruction" is equal to the rate of new "bone production." In children, however, the addition to new bone greatly exceeds the rate of loss that is how they grow!

The powerful muscles of the front surface of the upper leg are attached to the kneecap by a tendon. This is the tendon, by the way, that President Clinton recently tore. The kneecap, or patella in doctorese, is then attached to the lower leg bone the tibia by another tendon, the patellar tendon. The point at which the patellar tendon attaches to the tibia must be able to manage a high level of force. In adolescents this attachment area is still in the process of rapid growth. In some individuals the amount of force at the attachment area is more than the growing tissue can easily accommodate. This produces minor damage to the tibial bone, making the area swollen and tender, a process otherwise known as Osgood-Schlatter disease.

You can appreciate the kind of pressure that this attachment area of the patellar tendon must absorb when you think of the effort required to climb stairs or perform similar leg-straightening activities. Damage is most likely when the boy or girl participates in activities that require vigorous physical activity football, soccer, track, riding a bicycle, etc.

Treatment of Osgood-Schlatter disease is usually fairly simple. Excessive stress on the knee must be avoided for a few weeks while the area heals. Usually that just means sitting out the current season of sports and temporarily eliminating bicycle riding. In the most severely afflicted individuals, the knee must be supported in a brace for three or four weeks to get the healing process underway. Use of ice packs three or four times daily and taking ibuprofen or other NSAIDs can also help.

Fortunately, Osgood-Schlatter disease heals in everyone, just as your son's doctor told you. The new bump below the knee cap is permanent, however. I can personally attest to this fact because of the appearance of my own bumpy knees.

Family Medicine® is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, Grosvenor Hall, Athens, Ohio 45701.