The uptake of Tc-99m-diphosphonate was studied topographically and quantitatively on 258 diseased hips. For many diseased hips, bone scintigraphy provides items of information that complement the clinical, radiological, and biological data, with which it should always be compared. The localization, extent, and intensity of the uptake differ greatly according to the hip disorder studied, and depend not only on the cause of the lesion but also on its stage of evolution. Bone scintigraphy can shed light on the etiologic diagnosis of a painful hip at the beginning of its evolution, before definite roentgenographic signs appear, thanks to some very precise characteristics of the uptake, this is the case for transient osteoporosis of the hip, aseptic osteonecrosis, Legg-Perthes disease, early arthritis of the hip joint, and stress fractures of the femoral neck or of the pubic rami.