Transient synovitis of the hip: more evidence for a viral aetiology.

OBJECTIVES: Transient synovitis (TS) of the hip is a common cause of limping in children. A link with infection has been suggested but has not been firmly established. We conducted a case-control study to determine whether the TS is associated with infection.

METHODS: We enrolled children diagnosed with TS in our emergency department over a 10-week period. For each case, we identified an age-matched and sex-matched child with a fracture. Parents of cases and controls were questioned with regard to recent infectious illness in their child according to a predefined questionnaire.

RESULTS: A paired analysis showed that children with TS (N=29) were more likely to have experienced recent infection with vomiting or diarrhoea (P=0.004) and 'common cold symptoms/runny nose' (P=0.006) than the children with fractures (N=29). Other symptoms suggestive of either viral or bacterial infection were not significantly associated with TS.

CONCLUSION: TS is associated with symptoms of gastroenteritis and the common cold.