After these tests are completed, the subjects will go to the densitometry suite of the Endocrinology clinic where BMD will be measured and heel images obtained for texture analysis. The left heel will be scanned twice using the PIXI densitometer (GE/Lunar corporation) for measurement of BMD of the heel and texture analysis. (If there is a deformity of the left heel, right heel will be used for all examinations.) In addition, every 6 months, BMD of the lumbar spine and proximal femur will be measured using the central densitometer Prodigy (GE/Lunar corporation). The same instrument will be used for lateral vertebral assessment (a method used for detecting vertebral deformities on images of the lateral spine from the densitometer), which will be performed every 12 months.