Osteogenesis imperfecta (OI) is a genetic disorder leading to increased bone fragility. Recent work has shown that the hierarchical structure of bone plays an important role in determining its mechanical properties and resistance to fracture. The current study represents one of the first attempts to characterize the 3D structure and composition of cortical bone in OI at the micron-scale. A total of 26 pediatric bone fragments from 18 individuals were collected during autopsy (N_c=5) or routing orthopaedic procedures (N_OI=13) and imaged by microtomography with a synchrotron light source (SRμCT) for several microstructural parameters including cortical porosity (Ca.V/TV), canal surface to tissue volume (Ca.S/TV), canal diameter (Ca.Dm), canal separation (Ca.Sp), canal connectivity density (Ca.ConnD), and volumetric tissue mineral density (TMD). Results indicated significant differences in all imaging parameters between pediatric controls and OI tissue, with OI bone showing drastically increased cortical porosity, canal diameter, and connectivity. Preliminary mechanical testing revealed a possible link between cortical porosity and strength. Together these results suggest that the pore network in OI contributes greatly to its reduced mechanical properties.

Date Published: 29 March 2013
PDF: 9 pages
Proc. SPIE 8672, Medical Imaging 2013: Biomedical Applications in Molecular, Structural, and Functional Imaging, 86721L (29 March 2013); doi: 10.1117/12.2007209

Published in SPIE Proceedings Vol. 8672:
Medical Imaging 2013: Biomedical Applications in Molecular, Structural, and Functional Imaging
John B. Weaver; Robert C. Molthen, Editor(s)