What Is It?
Osgood-Schlatter disease is a common, temporary condition that causes knee pain in older children and teenagers, especially those who play sports and apply excessive stress to the patellar tendon (which connects the lower end of the knee cap to the upper part of the lower leg).
During activities that include a lot of jumping and bending — hockey, basketball, volleyball, soccer, skating, gymnastics, or ballet — the quadriceps muscle (thigh muscle) pulls tightly against the kneecap and the kneecap's anchor, the patellar tendon. The fibers of the patellar tendon are attached to the shinbone (tibia). With repeated pulling against these fiber connections, the tendon can become inflamed at or near its bone attachment. The result is pain and swelling at the tibial tuberosity, which is a raised area at the top of the shinbone. The tibial tuberosity is where the patellar tendon attaches to the bone.