Osteonecrosis: MR imaging versus plain radiography and nuclear scintigraphy

ABSTRACT

26 cases [23 males and 3 females] of a vascular necrosis [AVN] aged between 3 to 60 years diagnosed over two years were evaluated radiologically by plain radiography, nuclear isotopic scanning and MR imaging in the radiology department of Hamad General Hospital, Doha Qatar. 7 cases were around the hip joint, 9 knees, 7 ankles, 2 wrists and 1 shoulder. Radiological findings were compared and reviewed with the literatures regarding sensitivy and specificity of the technique used as well as MR appearance and staging. The plain radiography was either normal or non-specific in 12 cases [45%], while scintigrap[hy was normal in 8 and of non-specific increased radiotracer uptake in 18 cases [69%]. MR was positive for AVN in all cases. The hip cases of the study group showed different grades of MR staging based on the shape and both T1 and T2 signal characteristics of the involved aera using Kokubo and Lange et al., 92 classification, while knee and ankle cases showed mainly osteochondritis dessicans of different stages. We concludede that MRI is the most sensitive and specific radiological test and the modality of choice in the evaluation of avascular nercosis