Osgood-Schlatter disease is a condition in children that causes pain just below the knee. Sever disease is a condition in children that results in pain at the back of the heel.

What is going on in the body?

In children, the shin and thigh bones, which are known as the long bones of the legs, grow longer from the ends of the bones. These growing areas are called epiphyses. Tendons attach to the bones close to these growing ends. When the bones are very actively growing, vigorous exercise can cause the tendons to pull on the epiphyses. This can lead to irritation and swelling and can even interfere with the growth of the bone. When the swelling and pain occur just below the knee, it is known as Osgood-Schlatter disease. When the swelling and pain occur at the heel, it is called Sever disease. Both conditions occur most often in children between the ages of 10 and 15 years. Sever disease sometimes occurs in children as young as 8. Both conditions occur more often in very active children and affect boys slightly more often than girls.

What are the causes and risks of the disease?

A child between the ages of 10 and 15 years is at risk for developing these conditions if he or she is very active and plays sports that involve running, jumping, and stretching of the muscles in the lower legs.