Patient question
My teenager has a painful bump below the kneecap. What is it?
Dr. Pablo GelberOrthopaedic Knee Surgeon
Quick answer
A tender bony bump just below the kneecap in an active 10 to 15 year old is usually Osgood-Schlatter disease, an irritation of the growth area where the patellar tendon attaches to the shin. It is common, settles as growth finishes and rarely needs surgery, explains Dr. Pablo Gelber, knee surgeon at Aman Hospital, Doha.
Why it happens during growth spurts
In growing children, the patellar tendon pulls on a soft growth area at the top of the shin bone. During a growth spurt the bones lengthen faster than the muscles, so the thigh muscle becomes tight and pulls harder. Repeated running, jumping and kicking then irritate that spot, and the body lays down extra bone, which is the bump you can see and feel.
It is very common in children who play football, basketball, volleyball, gymnastics or athletics, and it can affect one or both knees.
Other possibilities a doctor will consider
- Sinding-Larsen-Johansson syndrome: the same kind of irritation but at the lower tip of the kneecap rather than on the shin
- Patellofemoral pain: a diffuse ache around the kneecap, common in teenage girls in particular
- Osteochondritis dissecans: a problem in the bone under the joint cartilage, more often with swelling, catching or ache after activity
- Hip problems in growing children can cause pain felt only in the knee, so a limp or hip stiffness needs an examination
Managing sport and daily life
Most children do not need to stop sport completely. Reduce the activities that clearly hurt, such as sprinting, repeated jumping or extra training sessions, and keep the ones that are comfortable. A pain level that stays mild during play and settles by the next morning is a reasonable guide.
Ice for 15 minutes after sport, gentle stretching of the thigh and calf, and strengthening the hips help. A pad over the bump is useful for kneeling, including in prayer. Symptoms often come and go for one to two years and usually stop when growth is complete, although the bump may remain.
When to bring your child to a specialist
Seek prompt medical care if the knee is red, hot and swollen, if your child has fever, night pain or cannot bear weight, or if pain followed a sudden injury. Book an assessment if pain stops them playing for weeks, if it is in an unusual place, or if they limp.
At Aman Hospital in Doha, Dr. Gelber examines the knee and hip and usually confirms the diagnosis clinically. An X-ray is sometimes taken to rule out other causes. Surgery is rarely considered, and only for persistent symptoms after growth has finished.
Frequently asked questions
Will the bump go away?
The pain usually settles once growth ends, but the bony bump often stays. It is normally harmless, though it can be tender when kneeling.
Is this the same as growing pains?
No. Growing pains are usually a night-time ache in both legs with no tender spot. Osgood-Schlatter disease has a clear tender bump below the kneecap and is linked to activity.
Related
