Bone health /Osteopenia/Osteoporosis posts can be placed on the Arthritis forum or General Health Conditions & Rare Disorders.
http://neurotalk.psychcentral.com/forum86.html
http://neurotalk.psychcentral.com/forum2.html
If you use Bone health /Osteopenia/Osteoporosis in title, and in the post - it will get noticed.