Toxic synovitis is a condition affecting children that causes hip pain and limping.
Synovitis - toxic; Transient synovitis
Toxic synovitis occurs in children before puberty. It usually affects children from 3 to 10 years old. It is a type of inflammation of the hip. Its cause is not known. Boys are affected more often than girls.
Symptoms may include:
- Hip pain (on one side only)
- Thigh pain, in front and toward the middle of the thigh
- Knee pain
- Low-grade fever, less than 101°F (38.33°C)
Aside from the hip discomfort, the child does not usually appear ill.
Toxic synovitis is diagnosed when other more serious conditions have been ruled out, such as:
Tests used to diagnose toxic synovitis include:
Other tests that may be done to rule out other causes of hip pain:
Treatment often includes limiting activity to make the child more comfortable. But, there is no danger with normal activities. The health care provider may prescribe nonsteroidal anti-inflammatory drugs (NSAIDs) to reduce pain.
The hip pain goes away within 7 to 10 days.
Toxic synovitis goes away on its own. There are no expected long-term complications.
Call for an appointment with your child's provider if:
- Your child has unexplained hip pain or a limp, with or without a fever
- Your child has been diagnosed with toxic synovitis and the hip pain lasts for longer than 10 days, the pain gets worse, or a high fever develops
Sankar WN, Winell JJ, Horn BD, Wells L. The hip. In: Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 698.
Singer NG. Evaluation of children with rheumatologic complaints. In: Hochberg MC, Gravallese EM, Silman AJ, Smolen JS, Weinblatt ME, Weisman MH, eds. Rheumatology. 7th ed. Philadelphia, PA: Elsevier; 2019:chap 105.