DXA-Based 3D Analysis of the Cortical and Trabecular Bone of Hip Fracture Postmenopausal Women: A Case-Control Study

Methods using statistical shape and appearance models have been proposed to analyze bone mineral density (BMD) in 3D from dual energy X-ray absorptiometry (DXA) scans. This paper presents a retrospective case-control study assessing the association of DXA-derived 3D measurements with osteoporotic hip fracture in postmenopausal women. Patients who experienced a hip fracture between 1 and 6 years from baseline and age-matched controls were included in this study. The 3D-SHAPER software (version 2.7, Galgo Medical, Barcelona, Spain) was used to derive 3D analysis from hip DXA scans at baseline. DXA and 3D measurements were compared between groups. Total hip areal BMD of hip fracture group as measured by DXA was 10.7% lower compared to control group. Differences in volumetric BMD (total hip) as measured by 3D-SHAPER were more pronounced in the trabecular compartment (-23.3%) than in the cortex (-8.2%). The area under the receiver operating curve was 0.742 for trabecular volumetric BMD, 0.706 for cortical volumetric BMD, and 0.712 for total hip areal BMD. Differences in the cortex were locally more pronounced at the medial aspect of the shaft, the lateral aspect of the greater trochanter, and the superolateral aspect of the neck. Marked differences in volumetric BMD were observed in the greater trochanter. This case-control study showed the association of DXA-derived 3D measurements with hip fracture. Analysis of large cohorts will be performed in future work to determine if DXA-derived 3D measurements could improve fracture risk prediction in clinical practice.