I want to measure the length and width of a vertebra?

Hi, I have an ongoing project and am at the stage I need to measure the height (of the midpoint of the vertebral body) of L2 and L5, and length (in CT scans)? I have approx. 20 data sets to complete. I have used the segmentation stats for the volume which gives some of the data I need but now need to measure specifics. Please can someone advise/help? Many thanks Sandie