Transient Synovitis

Abstract

Transient synovitis (TS) is the usual pathological cause of an “irritable hip” (IH). TS is a benign self-limited condition in which there is inflammation of the hip synovium and likely an effusion. The clinical features typically last not more than 14 days, and have no adverse sequelae. There are many possible aetiologies for an IH, and most of these are similarly self-limited and benign. The diagnoses of TS and benign IH are of exclusion, albeit that in practice, they are usually made presumptively in primary care or the emergency department, and without hospital admission. It is proper for most cases to be managed at this level-except for cases that have symptoms persisting beyond 14 days and/or demonstrate progressive features and/or deterioration. These cases mandate early review and investigation for differential diagnoses. An important differential diagnosis to rule out is early infection (especially septic arthritis/osteomyelitis/pyomyositis). In cases of concern, joint aspiration under anaesthaesia is potentially diagnostic.