Toxic synovitis is an inflammation within the hip joint.
Toxic synovitis is a non-traumatic hip pain, which means that it is not caused by an injury. Instead, pain is caused by swelling and inflammation in the hip. Toxic synovitis often follows an upper respiratory infection such as a cold or flu.
The person with the illness often refuses to walk or walks with a limp. Children 2 years old are most often affected, although it also strikes children between the ages of 3 and 10. It appears to be more common in boys than girls.
The cause of toxic synovitis is not known. It often follows an upper respiratory infection.