[en] It was the aim of this study to describe the different density patterns produced by various forms of aseptic osteonecrosis. Comparative evaluations of X-ray pictures and scintiscans were carried out in order to establish, if skeletal scintiscanning permits a specific diagnosis to be made and to distinguish between the early and late stages of a disease. A further question to be clarified within the framework of this study was the frequency and cause of femural head necrosis in patients having received kidney transplants. For this purpose, combined skeletal and renal function scintiscans were obtained following single injection of 99mTc-MDP. It was found that Perthes disease and femural head necrosis could be diagnosed from the scintiscans 2-3 months before any pathological changes were discernible on the X-ray pictures, as incipient circulatory disorders are already reflected by reduced concentrations of activity; knee joint necrosis, infarction of bone tissue and osteochondrosis were associated with an increased accumulation of the tracer substance, from the initial through the later stages of these diseases; among 32 patients with kidney transplants, 11 were shown to have developed femural head necrosis and other pathological changes could be predicted from the skeletal scintiscans in a furter 14 cases. It was concluded that skeletal scintiscanning carried out on a routine basis in patients with kidney transplants is a very meaningful procedure for the immediate diagnosis of femural head necrosis and, thus, post-operative surveillance. (TRV)