CT versus MRI in diagnosis of early avascular necrosis of femoral head

Objective  To compare the value of computed tomography (CT) and magnetic resonance imaging (MRI) in the diagnosis of early avascular necrosis of femoral head. Methods  Totally 36 patients (47 hips) with avascular necrosis of femoral head were selected and diagnosed by surgical pathological examination. All the patients underwent CT and MRI examinations respectively, and the results of surgery were used as the standard to judge the efficacy of CT and MRI in the diagnosis of early avascular necrosis of femoral head. Results  In this study, 29 patients with early avascular necrosis of femoral head (38 hips) were confirmed by surgical pathology. The positive detection rate, sensitivity and specificity of MRI for early avascular necrosis of femoral head were 97.37%, 97.30% and 80.00% respectively, which were higher than 78.95%, 76.67% and 11.76% of CT (χ2=4.537, 4.887, 9.815, P=0.033, 0.027, 0.001). Conclusion  CT and MRI have their own advantages and disadvantages in the diagnosis of early avascular necrosis of femoral head. Compared with CT, MRI has higher positive detection rate, sensitivity and specificity.