抄録
A method to measure cortical thickness of rat tibia with 10-fold image magnified by a projector from soft X-ray radiograph of legs proved to have a high precision. Reproducibility study based on X-ray pictures obtained by five times sequential radiographing in three rats revealed that the mean and standard deviations of percentage coefficients of variation were 0.20±0.04 in external diameter (D), 0.80±0.43 in internal diameter (d) and 0.83±0.21 in combined cortical thickness (D-d).
Bone index L(D2-d2) (L: bone length) showed a good correlation with fat-free dry bone weight (n=29, r=0.843). The most suitable index for normalizing skeletal size was (D2-d2)/D.