Figure 1.

Steps to acquire computed tomography (CT) images after CT three-dimensional reconstruction. Taking femoral neck as research object, stipulated that axial section was the section perpendicular to the central axis of the femoral neck. The sagittal and coronal planes were referenced to femoral neck, and three planes were perpendicular to each other. (A) Sagittal CT image of the femoral neck, the green line represented the coronal plane direction, parallel to both the anterior cortex and the central axis of the femoral neck. (B) Coronal CT image of the femoral neck, the orange line represented the sagittal plane direction, parallel to the central axis. (C) Axial CT image of the femoral neck, that is, the slice direction of the blue line in A and B, perpendicular to both the green and orange lines. The blue, green, and orange lines were perpendicular to each other, forming three vertical planes of the spatial coordinate system.