Understanding how bone adapts in mass, geometry, strength to weight gain during childhood is important from both a public health and basic bone biology standpoint. While the prevailing thought is that obesity is protective of bone and lowers the risk of fractures, there is evidence to suggest that the opposite may be true. While obese adults have increased risk of forearm and lower leg fractures, obese children may be at a higher risk of forearm fractures. Therefore, it is important to understand how bone adapts its mass, geometry and strength during weight gain leading to obesity during childhood.
Previous studies have used dual energy x-ray absorptiometry (DXA) outcomes of areal bone mineral density (aBMD, g/cm2) and bone mineral content (BMC, g) to estimate bone strength. DXA outcomes provide an important predictor of fracture risk; more bone generally confers greater strength. However, bone geometric adaptations may not be elucidated in aBMD outcomes, but may provide greater information regarding parameters of bone strength. In the LMH we have the opportunity to study bone adaptation through the use of peripheral quantitative computed tomography (pQCT), which allows for three-dimensional imaging of the peripheral skeleton.