[Comparative study of scintigraphy, x-ray computed tomography and magnetic resonance imaging in the diagnosis of osteonecrosis of the hip and algodystrophy].

Effectiveness of modern imaging techniques were compared when used for diagnosis of the painful hip in adults, particularly the distinction between aseptic osteonecrosis and decalcifying osteodystrophy. Although a small number of patients were studied (5 cases of osteonecrosis and 5 of decalcification) the series was homogeneous (same investigator for each technique and identical equipment for each patient), and the different methods of investigation (conventional radiology, scintigraphy computed scanography CE 10,000 and 0.15 resistive NMR imaging) could be validly compared. NMR images were recorded in only 5 patients but evaluation involved findings during use of this method of hip investigation over a period of 8 months. Results of comparison of the different imaging methods in osteonecrosis and osteodystrophy of hip showed conventional radiology to be much less effective for diagnosis. Conventional bone scintigraphy appeared to provide a good diagnostic approach, while C.T. images appeared to be as effective or even more specific than scintigraphy for differential diagnosis of the two affections. The only uncertainty is based on the radiologic latency in early stage disease, probably able to be filled by a densitometry. The use of NMR imaging appears to be promising, since it provides data as early as scintigraphy and as specific as scanography, particularly in view of apparent discrimination between osteonecrosis and osteodystrophy of the hip with respect to measurement of relaxation parameters.