Thanks Laura, that is also what the endocrinologist told us and why he thought my son may grow another inch, however he grew 3 inches!  There is something not quite right though as the end of the growth plates in his spine are now irregular causing a loss of vertebral height. I know the specialist, who is world renowned for his work in CAH and growth hormone treatment, was most surprised at the growth. Bone density shows the density (thickness/strength) of the bones which is used as an indicator for osteoporosis. I think this is important to keep a check on through the teenage years and adulthood. As my son is on a higher than normal dose, he has had several of these scans and has low bone density