Osteoporosis is the thining of bones due to loss of calcium, and which usually occurs in genetically predisposed post-menopausal women. (This is to be distinguished from Osteoarthritis which is the same as "degenerative" or "old age" arthritis.) In the illustration above, the osteoporotic compression fracture can now be reexpanded and stabilized with "bone cement." This proceedure, known as Kyphoplasty, takes about 45min to perform and requires just one onight stay in the hospital. Check out the Kypon site above for more information.