Osgood-Schlatter’s disease usually occurs in teenagers. It causes pain and swelling just below the knee. It is named after the two people who first described it. It is not serious and usually goes away in time.
Who gets Osgood-Schlatter’s disease?
Young teenagers, particularly boys, are the most commonly affected. It is uncommon over the age of 16. It is more common in teenagers who play a lot of sport involving kicking, running, or jumping. These kinds of sports cause repeated and vigorous use of the quadriceps muscles. However, it can also occur in children who are not sporty.
Symptoms of Osgood-Schlatter’s disease
The main symptom is pain just below the kneecap (patella). The severity of the pain tends to flare up and down. It is usually worse during, and just after, activity. It tends to ease with rest.
The pain typically lasts a few months, but sometimes persists until you have finished growing. This means that in some cases it can last up to two years.
A small, tender, bony bump may develop a few centimetres below the kneecap. This occurs where the patella ligament attaches to the tibia (shin bone). The small bump is permanent, although in time it becomes painless. The actual knee joint is not affected, so knee movements are normal. Symptoms usually occur just under one kneecap, but in up to one in three cases it affects the area under both kneecaps.
No tests are usually needed as the diagnosis is often clear from the typical symptoms.
Causes of Osgood-Schlatter’s disease
Sometimes it develops for no apparent reason. However, overuse of the front thigh muscles (quadriceps) is thought to be a common cause. The quadriceps muscle is used to straighten the knee. This muscle pulls on the patella, which pulls on the patella ligament, which is attached to the upper part of the tibia.
Overuse of the quadriceps muscle can cause repeated stress and strain on the attachment of the patella ligament to the growing tibia. This can cause inflammation and pain at the site of the ligament attachment. In some cases, a small flake of bone is pulled off the tibia by the pulling ligament. Healing bone (callus) then forms which may cause a hard bony bump to develop.