vBMD and automatic segmentation

Hello,

I am new to 3D Slicer and I need to segment the femoral neck and calculate the vBMD of the femur from CT, if possible that the regions of interest can be automatically selected. The goal is to compare the pre- and post-intervention results.

Could anyone provide guidance or resources on how possibility to do that using 3D Slicer? Any tips or recommendations would be greatly appreciated.

Thank you