https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4440196/
Hi @lebanon100, above is a link to a paper which reviewed studies of vibration machines on women with osteoporosis. If the link doesn't work, google, "Whole-body vibration exercise in post menopausal osteoporosis" and you will be able to access the article.
After reading this paper, I decided to purchase one. There is a large selection of these machines on Amazon - I chose the Eilison Bolt, which is a smaller machine, easier for me to handle, works on carpet, with a yoga mat under it, and has a five year warranty. I took a few weeks to work up to the programs Eilison claims increase bone density. There is also a more expensive machine, developed in conjunction witrh NASA to help the astronauts increase their bone density upon their return to earth. That one is called the Marodyne. You can Google it. Last time I checked, it cost about $1600.00. I did make some inquiries, but never saw any replies from the company so I bought the BOLT., which cost about $150.00. I wish you the best.