Prediction of collapse in femoral head osteonecrosis: role of volumetric assessment

Abstract

Purpose: The purpose of this study was to evaluate and compare the accuracy of three different techniques of measuring the extent of osteonecrosis involvement of the femoral head on MRI to determine the best predictor of collapse and to identify the size of the lesion volume which best predicts collapse. Methods: We prospectively enrolled 48 hips of osteonecrosis femoral head (ONFH) with stage 1 or 2 osteonecrosis and the enrolled patients were followed up for 1 year. Angular measurements (modified Kerboul Angle and modified index of necrotic extent) were compared with the 3D volumetric measurement of necrotic lesion based on MRI in predicting the collapse of the head. ROC analysis was done to evaluate the diagnostic performance of the 3 indices in predicting collapse. Survival analysis of all the hips in the collapsed and non-collapsed group were interpreted using Kaplan Meir survival analysis. Results: In lesion sizes larger than 25% of femoral head volume - 90.6% (29/32) of hips collapsed within 1 year as compared to 31.3% (5/16) hips collapsed in lesion volume <25% of femoral head (Log-rank test p = 0.001). There was good inter-observer (ICC, 0.94; 95% CI, 0.89–0.97) and intra-observer reliability (ICC, 0.93; 95% CI, 0.88–0.96). Conclusions: The Volumetric method assessed the severity of lesion size with the future collapse better and more predictably than angular measurements. Necrotic lesion volume of 25% is a potential cut off beyond which future collapse of early ONFH can be predicted and aid in the further management. This study can help in solving the mystery behind prediction of collapse in ONFH.

Volume and location of bone regeneration after autologous expanded mesenchymal stromal cells in hip osteonecrosis

“…Manual calculation in all MRI sections, a cumbersome task, has also been criticised due to the potential inter- and intraobserver variability in determining the reference FHV. 31 - 33 We performed both manual (based on the anatomical contour) and automatic (based on a spherical model) calculations of the femoral head, as mentioned in Supplementary Figure b. Data shown in the results are obtained as a percentage of the manual measured FHV.…”

The Role of Structural Deterioration and Biomechanical Changes of the Necrotic Lesion in Collapse Mechanism of Osteonecrosis of the Femoral Head

“…Ansari et al 42 . drew the necrotic area in outline in coronal planes of MRI, calculated the necrotic lesion/the entire femoral head area ratio in each slice, and finally determined the sum of the area ratio multiplied by the slice thickness to obtain the volumetric measurement.…”

“…Ansari et al . 42 drew the necrotic area in outline in coronal planes of MRI, calculated the necrotic lesion/the entire femoral head area ratio in each slice, and finally determined the sum of the area ratio multiplied by the slice thickness to obtain the volumetric measurement. Their results showed that 90.6% of hips collapsed within 1 year in lesion volume greater than 25% of femoral head, while 31.3% of hips collapsed in lesion volume less than 25%.…”

3D MRI of the Hip Joint: Technical Considerations, Advantages, Applications, and Current Perspectives

“…Partial-volume artifacts are minimized on sub 1.0-mm 3D acquisitions. Accurate assessment of lesion size, 61 its location, presence of joint synovitis, and early osseocartilaginous collapse, are important for surgical decision making. High-resolution 3D MRI is able to demonstrate such fine details (►Fig.…”