Quantitative CT for the evaluation of bone healing.

Quantitative computed tomography (QCT) was used to quantitate the structural strength and local material properties of healing tibial osteotomies in 32 dogs. Dogs were divided into four equal groups, euthanatized at either 2, 4, 8, or 12 weeks and imaged with QCT. Invasive techniques were used to determine (1) the torsional properties of the bone; (2) the local stiffness properties and calcium content within the bone; and (3) histologically determined new bone formation and porosity. QCT was strongly associated with the maximum torque (R2 = 0.44) and torsional stiffness (R2 = 0.69) of the healing bone. QCT had strong correlations with the local stiffness (R2 = 0.64), calcium content (R2 = 0.61), new bone (R2 = 0.84), and porosity (R2 = 0.84) of healing tissues.