How does type 1 osteoporosis affect the spine?

The outer shell of bone is solid, whereas the inner part is spongy and lacy. Because it responds more quickly to changes in the chemical environment of the body, spongy tissue is more affected by the drop in estrogen that occurs at the time of menopause. Since the bones in the spine (the vertebrae) are composed mostly of spongy bone, they are the bones that become thin most rapidly if you have type 1 or postmenopausal osteoporosis.