Guen Young Lee, Presenter: Nothing to Disclose

Jung-Ah Choi MD, Abstract Co-Author: Nothing to Disclose

Kyung-Hoi Koo MD, Abstract Co-Author: Nothing to Disclose

Yong-Chan Ha, Abstract Co-Author: Nothing to Disclose

Baek Hyun Kim MD, Abstract Co-Author: Nothing to Disclose

Heung Sik Kang MD, Abstract Co-Author: Nothing to Disclose

We aimed to demonstrate the usefulness of MDCT in early detection of cortical collapse in osteonecrosis of femoral head, compared with hip MRI. We also aimed to evaluate and compare the extent of osteonecrosis on both MDCT and MRI according to Ficat and Arlet staging, using modified Kerboul method.

From January, 2005 to December, 2009, total 281 hips of 183 patients were evaluated in this study, which underwent both MDCT and MRI. For the evaluation of cortical collapse, we reviewed and staged axial and coronal reconstructed MDCT images and axial and coronal MR images based on Ficat and Arlet staging system and compared the results of MDCT and MRI by Chi-square test. Excluding 91 hips without available sagittal MR images, the extent of osteonecrosis was evaluated in 190 hips on coronal and sagittal MDCT and MR images, using modified Kerboul method, and analyzed by Student T-test, one-way ANOVA, and Pearson correlation test.

Among 281 hips, 55 cases of Ficat and Arlet stage 3 and 25 cases of stage 4 on MDCT were understaged as stage 2 (51.9%) and stage 3 (46.3%) on MRI, respectively. Seventeen hips of stage 4 on MDCT were underestimated as stage 2 on MRI (10%). Staging on MRI based on cortical collapse was downgraded compared with that of MDCT (Chi-square test, p=.000). In 190 hips, each measured angle by Kerboul method was not different between MDCT and MRI (Paired T-test, p=.752). However, measured angle using Kerboul method differed on both MDCT and MRI (one-way ANOVA, p=.000) according to Ficat and Arlet stage. There was a positive correlation between Ficat and Arlet stage and measured angle by Kerboul method on both MDCT (Pearson correlation test, γ=.275, p=.000) and MRI (Pearson correlation test, γ=.214, p=.003).

MDCT may be more useful for the detection of subchondral collapse or cortical flattening than MRI in osteonecrosis of hip. Using modified Kerboul method, the prediction of cortical collapse may be possible on MDCT similarly to MRI.

Using MDCT, staging and prediction of prognosis in osteonecrosis of hip may be more easier and reproducible in practice than MRI.  

Lee, G, Choi, J, Koo, K, Ha, Y, Kim, B, Kang, H, The Usefulness of MDCT in Early Detection and Prediction of Cortical Collapse in Osteonecrosis of Femur Head Using Modified Kerboul Method: Comparison with MRI.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9006628.html