Q My son has Osgood-Schlatter’s disease. Is it serious?

AThis knee condition is caused by continued traction from the quadriceps giving repetitive injury to the growth plate of the tibia, causing pain and swelling at the patella tendon insertion. Similarly, Sinding-Larsen-Johansson syndrome causes inflammation at the insertion of the patella tendon on the lower end of the patella. The condition is associated with adolescent growth spurts. Regular high-impact sports, such as running, football and gymnastics, cause repeated strain. It typically develops gradually, being intermittently painful after sporting activities but not painful if resting. X-rays are usually normal but may be needed to exclude other diagnoses such as bone tumours, infection, juvenile or reactive arthritis, and vitamin D deficiency. It’s not dangerous and will improve as growth slows over 12-24 months. Management includes pain relief (ibuprofen) and ice packs, and exercises to stretch tight muscles before sport. Sports such as swimming will be fine, but activities such as football are likely to cause flare-ups. The condition will eventually resolve.