Skip navigation

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

URL of this page: //medlineplus.gov/ency/article/000981.htm

Toxic synovitis

Toxic synovitis is a condition affecting children that causes hip pain and limping.

Causes

Toxic synovitis occurs in children before puberty. It usually affects children from 2 to 12 years old. It is a type of inflammation of the hip. Its cause is not known. Boys are affected more often than girls. It can also occur after a common cold or viral infection.

Symptoms

Symptoms may include:

  • Hip pain (on one side only)
  • Limp
  • Thigh pain, in front and toward the middle of the thigh
  • Knee pain
  • Low-grade fever, less than 101°F (38.33°C)
  • Child only walking on toes and refusing to walk normally

Aside from the hip discomfort, the child does not usually appear ill.

Exams and Tests

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

Treatment often includes limiting activity to make the child more comfortable. But, there is no danger with normal activities. Your child's health care provider may prescribe nonsteroidal anti-inflammatory drugs (NSAIDs) to reduce pain.

Outlook (Prognosis)

The hip pain goes away within 7 to 10 days.

Possible Complications

Toxic synovitis goes away on its own. There are no expected long-term complications.

When to Contact a Medical Professional

Contact your child's provider for an appointment 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

Alternative Names

Synovitis - toxic; Transient synovitis

References

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, Onel KB. Evaluation of children with rheumatologic complaints. In: Hochberg MC, Gravallese EM, Smolen JS, van der Heijde D, Weinblatt ME, Weisman MH, eds. Rheumatology. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 103.

Review Date 8/30/2023

Updated by: Neil K. Kaneshiro, MD, MHA, Clinical Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

Related MedlinePlus Health Topics