|
KMID : 0386720040160040410
|
|
Journal of the Korean Hip Society
2004 Volume.16 No. 4 p.410 ~ p.416
|
|
|
Measurement of the Extent of Femoral Head Osteonecrosis with a Modified Kerboul Method Using MRI
|
|
Kim Tae-Yoon
Koo Kyung-Hoi
Jung Soon-Taek
Ha Yong-Chan
Choi Won-Chul
|
|
|
Abstract
|
|
|
Purpose: We tested the hypothesis that combined necrotic angle measurement using MRI scans can predict the subsequent risk for collapse of femoral head osteonecrosis.
Materials and Methods: Thirty-seven hips with early-stage (Ficat stage I, IIA or IIB) osteonecrosis in 33 consecutive patients were investigated. The arc of the necrosis was measured by the method of Kerboul et al. using the mid-coronal and mid-sagittal MRI scans of the femoral head instead of the anteroposterior and lateral radiographies, and the two angles were added. The patients´ hips were classified into four categories based on the magnitude of the added angle; grade 1(<200°), grade 2(200°~249°), grade 3(250°~299°), and grade 4(>300°). After the initial evaluations, the hips were randomly assigned to the core-decompression group or the conservativelytreated group. Patients underwent regular follow-up until the femoral head collapsed or for a minimum of five years.
Results: Seven grade 4 hips and 16 grade 3 hips developed femoral head collapse within 36 months; six out of nine grade 2 hips, and none of five grade 1 hips developed collapse (log rank test, p<0.01). On the retrospective analysis, none of the four hips with a combined necrotic angle <190°(the low risk group) collapsed, all 25 hips with a combined necrotic angle >240°(the high risk group) collapsed, and four (50%) of eight hips with a combined necrotic angle between 190°and 240°(the moderate risk group) collapsed during the study.
Conclusion: The Kerboul combined necrotic angle ascertained by MRI scans instead of using radiographies might be a major predictor of future collapse for osteonecrosis of the femoral head.
|
|
|
KEYWORD
|
|
|
Hip, Femoral Head, Osteonecrosis, MRI
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
 
|
|