title: Bilateral Perthes' disease.
abstract: Bilateral Perthes' disease is defined as the form of the condition where radiological changes affect both hips simulatneously. The radiological abnormalities are commonly more severe on one side than on the other. In a small proportion of patients a clear time interval exists between the onset of radiological changes in the two hips. It is suggested that this form of the condition is two unilateral and separate attacks of Perthes' disease and it is more akin to 'recurrent' Perthes' disease.
mesh_terms: D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D005271:Femur Head Necrosis / Q000000981:diagnostic imaging*; D006615:Hip / Q000000981:diagnostic imaging; D006801:Humans; D007873:Legg-Calve-Perthes Disease / Q000000981:diagnostic imaging*; D008297:Male; D011859:Radiography; D012008:Recurrence; D013997:Time Factors