Toxic synovitis.

Department of Orthopedics, Pediatric Orthopedic Division, University of Wisconsin Hospital, 600 Highland Avenue, K4/732 CSC, Madison, WI 53792, USA.
Skeletal Radiology (Impact Factor: 1.74). 08/2008; 37(11):963-5. DOI: 10.1007/s00256-008-0543-3
Source: PubMed

ABSTRACT When a child develops hip pain or limping, it draws the immediate apprehension of parent and physician alike, despite the fact that the vast majority of these children will improve with little or no treatment. The concern is with the differential diagnosis because the symptoms of benign disorders of the hip may mimic serious disease and distinguishing between them can be quite difficult and often time dependent. Toxic synovitis (TS), also known as acute transient synovitis of the hip, is a condition in which there is nonspecific inflammation and hypertrophy of the synovium with an effusion in the hip joint. It is the most common cause of acute hip pain in children aged 3–10 years, and up to 3% of children have an episode at some time during their life. It is extremely uncommon in adults [9]. Although the diagnosis is usually one of exclusion, the etiology is unclear; parenthetically, many of these children have had an upper respiratory illness shortly before the onset of hip pain. Nearly all children recover within 2 weeks and without long-lasting effects. Four to 17% of children may have a recurrent episode. Children with recurrent episodes usually have a benign course, although, in about 10%, recurrent TS may be the presenting feature of a chronic inflammatory condition [10]. Treatment for TS focuses primarily on rest and anti-inflammatory medications, which shorten the course of the disorder [2]. While the treatment is rather straightforward, arriving at the diagnosis may be difficult. The differential diagnosis for a limping child with