This is generally a self-limiting process which occurs in the tibial tubercle at the insertion of the patellar tendon in active adolescents. This is more common in boys than in girls, and is frequently due to jumping or other resisted flexed-knee activities. This is a problem that occurs because the tendon puts pressure on the growth plate, which then causes irritation in the apophysis in the front of the knee. This can lead to soreness and irritation, and often to overgrowth of the bone in this area. Most of these problems will do well with conservative measures including activity modification, an isometric quadriceps strengthening program, and hamstring stretching. Once growth has been completed, the symptoms will generally resolve. A small percentage of patients will have a small fragment of bone, called an ossicle, which fails to unite when growth is completed. This may continue to cause pain even into adulthood. This can then require a subsequent surgical removal.
In most cases the patients may continue with activities as tolerated, although they may need to rest if symptoms increase. Patellar tendon strapping and physical therapy can also be helpful. If symptoms become severe, then a trial of a knee immobilizer and rest or possibly even a cast is occasionally necessary.