1. Transient synovitis is an acute, and at times exudative, condition of the synovial membrane.

2. There is no particular association with injury or with upper respiratory infection.

3. The course is short and benign with complete resolution. The occasional hip with chronic or recurrent symptoms can be distinguished from Legg-Perthes' disease by the shorter history, normal radiographs and the complete resolution.

4. There is no evidence that transient synovitis leads to avascular changes in the femoral head.