T1D is primarily associated with decrements in bone strength due to disrupted microarchitecture occurring during peak bone mass accrual, and this disruption arises from hyperglycemia and glycemic variability. Impaired bone development during this period likely predisposes to an increased fracture risk across the lifespan.

The investigators will compare baseline, 12 month and 24 month changes in High-resolution peripheral quantitative computed tomography/micro-finite element analysis (HR-pQCT/FEA)-based estimates of bone strength and bone turnover by biochemical measurements in 40 T1D children at the onset of peak bone mineral accretion (n=40) versus sex and puberty-matched healthy controls (n=40). The investigators will determine relationships between changes in bone strength (including trabecular and cortical components) and measures of glycemic control and variability by continuous glucose monitoring (CGM).