[Scintigraphic characteristics of coxopathies: etiologic importance].

Morphological and quantitative studies of the uptake of diphosphonates labelled with technetium 99m were done on 179 pathological hips : 106 aseptic osteonecroses of the femoral head, including 20 at an early stage, 11 algodystrophias (transitory osteoporoses of the hip), 20 coxarthrosis, 16 cases of Paget's disease, 12 isolated malignant lesions of the femoral neck. The location, extent and intensity of the uptake are very variable and depend not only on the etiology of the lesions but also on their stage of evolution. Bone scintigraphy provides, for numerous pathological hips, pieces of information which complete the results of the clinical, radiological and biological study, with which it should always be compared. It can shed light on the etiologic diagnosis of a painful hip at the beginning of its evolution, before the appearance of rare x-ray signs, thanks to certain very precise characteristics of the labelling. This is the case for algdystrophias, osteonecroses, coxitis and strain fractures of the femoral neck.