Get exclusive member benefits & effect social change. Join Today
Toxic synovitis is a temporary condition that causes hip pain in children. It’s also known as transient synovitis.
Toxic synovitis mainly occurs in children between the ages of 3 and 8. It’s two to four times more common in boys than in girls.
Although it’s troubling for parents, this condition usually clears up on its own within a week or two and causes no lasting damage.
Toxic synovitis occurs when there’s inflammation in the hip joint. The cause is unknown, but it often occurs after a viral infection. It usually only affects one hip, but it’s possible for swelling and inflammation to spread to other joints.
The most common symptom of toxic synovitis is hip pain. This pain might occur on and off in one or both hips. It might flare up when your child gets up after sitting or lying down for a long time.
Other symptoms include:
Common signs of toxic synovitis in babies include crying, especially when moving their hip joints, and unusual crawling movements. Being unwilling or unable to crawl is another common sign.
Toxic synovitis can be difficult to diagnose. Other conditions that are much more serious can also cause hip pain. Since these conditions require prompt medical treatment, your child’s doctor must first test for them before making a toxic synovitis diagnosis. These include the following:
Your child’s doctor will perform a physical exam to find out which movements are causing pain. This involves moving your child’s hips, knees, and other joints.
Your doctor might order an ultrasound of your child’s hip to check for fluid in the joint, which is a sign of inflammation.
Blood tests can show how severe the swelling is. Your child’s doctor might also check for other causes of hip pain, such as Lyme disease. They might remove a fluid sample and send it to a lab for testing. This is usually done when the swelling or fever is serious and septic arthritis hasn’t been ruled out.
Your child’s doctor might take X-rays to rule out Legg-Calve-Perthes disease or SCFE.
Treating toxic synovitis involves controlling or reducing its symptoms. The inflammation caused by the viral infection generally goes away on its own.
Over-the-counter (OTC) medications such as ibuprofen and naproxen can help reduce inflammation temporarily. This can provide short-term pain relief. Your child’s doctor might prescribe a stronger pain reliever if OTC medications don’t work.
Your child should rest the affected hip to help it heal. Walking is usually safe, but your child should avoid strenuous activities, such as contact sports. Your child should also try not to put too much weight on the hip.
Although this condition is rarely serious, you should call your child’s doctor if:
In these cases, your child’s doctor might need to prescribe a different medication or perform additional tests to check for other causes of hip pain.
Toxic synovitis clears up in about one to two weeks in most cases, but it can last as long as five weeks. It can occur repeatedly in some children when they have viral infections like colds.
Written by: Amanda Delgado
Medically reviewed on: May 26, 2017: William Morrison, MD
Enter your symptoms in our Symptom Checker to find out possible causes of your symptoms. Go.
Enter any list of prescription drugs and see how they interact with each other and with other substances. Go.
Enter its color and shape information, and this tool helps you identify it. Go.
Find information on drug interactions, side effects, and more. Go.