Collapse-related bone changes at multidetector CT in ARCO 1-2 osteonecrotic femoral heads: correlation with clinical and MRI data

Objective To assess the frequency of collapse-related bone changes at multi-detector CT (MDCT) in osteonecrotic femoral heads (ONFH) and to compare clinical parameters and MR' findings in Association Research Circulation Osseous (ARCO) 1-2 ONFH with or without collapse-related bone changes (CRBC) at MDCT. Materials and methods This is a secondary analysis of radiographic, MRI, and MDCT examinations of ONFH of patients eligible for a prospective clinical trial. Radiographs and MM were analyzed to perform ARCO staging. Frequency of CRBC at MDCT including cortical interruption. trabecular interruption, impaction, and resorption was determined by two readers (R1, R2) blinded to radiographic, MRI, and clinical data. Baseline clinical and imaging data of ARCO 1-2 ONFH were compared between hips with or without CRBC at MDCT. Results One hundred thirty-two hips of 77 participants were analyzed. There were 78 non-collapsed and 54 collapsed ONFH. For R1 and R2, 31/78 (40%) and 20/78 (26%) ARCO 1-2 ONFH and 54/54 (100%) and 53/54 (98%) ARCO 3-4 ONFH showed at least one CRBC at MDCT. For both readers. there was no significant difference in pain, functional impairment, size of lesion, and the presence of BME on MRI between ARCO 1-2 hips with or without CRBC at MDCT. Conclusion Twenty-six to forty percent of ARCO 1-2 ONFH demonstrate at least one collapse-related bone change at CT. Their clinical and MM findings do not differ from those without collapse-related bone changes.

Automated summary

This study aimed to assess the frequency of collapse-related bone changes at multi-detector CT (MDCT) in osteonecrotic femoral heads (ONFH) and compare clinical parameters and MR findings in ARCO 1-2 ONFH with or without CRBC at MDCT. The results showed that 26-40% of ARCO 1-2 ONFH demonstrated at least one collapse-related bone change at CT.