Transient synovitis tends to occur in children younger than 11 years old.
It is sometimes called toxic synovitis.
Symptoms of Transient Synovitis
Transient synovitis causes inflammation and pain around thehip joint.

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The symptoms tend to begin quickly over 1 to 3 days and usually resolve over the next several days.
Bacterial infections of the hip joint are more serious and may require surgery for treatment.
Blood work can be done to assess for signs of infection and inflammation.
Unfortunately, the results of these studies can be similar in both synovitis and infection.
Patients with a bacterial infection in the hip joint will have pus in the joint.
These children will have surgery to clean out the infection.
Children who have a bacterial infection tend to rapidly worsen, while children with synovitis steadily improve.
The child should be watched by a parent or responsible caregiver to ensure their condition does not worsen.
In addition, regular temperature checks are important.
Fevers should be reported to your healthcare provider.
Children who have transient synovitis of the hip usually recover completely.
2014;472(5):1645-1651. doi:10.1007/s11999-013-3142-0