Hi Vik,
My personal preference for segmentation of thoracic skeletal bones is using the new “local threshold” function of the “Segment Editor”, but this requires a few mouseclicks for each dataset. Another option would be the involvement of “Grow from Seeds” as described in this thread: Bone segmentation to create 3D-printable STL
Once you have defined a good workflow you can try to integrate it into a python script that loads the DICOM dataset, then lets you do the manually assisted segmentation, automatically saves the results, and switches to the next patient.
Regards,
Rudolf