Reduced diaphyseal strength associated with high intracortical vascular porosity within long bones of children with osteogenesis imperfecta. Bone 2014 Sep;66:121-30
Date
06/15/2014Pubmed ID
24928496Pubmed Central ID
PMC4467578DOI
10.1016/j.bone.2014.05.022Scopus ID
2-s2.0-84902982734 (requires institutional sign-in at Scopus site) 29 CitationsAbstract
Osteogenesis imperfecta is a genetic disorder resulting in bone fragility. The mechanisms behind this fragility are not well understood. In addition to characteristic bone mass deficiencies, research suggests that bone material properties are compromised in individuals with this disorder. However, little data exists regarding bone properties beyond the microstructural scale in individuals with this disorder. Specimens were obtained from long bone diaphyses of nine children with osteogenesis imperfecta during routine osteotomy procedures. Small rectangular beams, oriented longitudinally and transversely to the diaphyseal axis, were machined from these specimens and elastic modulus, yield strength, and maximum strength were measured in three-point bending. Intracortical vascular porosity, bone volume fraction, osteocyte lacuna density, and volumetric tissue mineral density were determined by synchrotron micro-computed tomography, and relationships among these mechanical properties and structural parameters were explored. Modulus and strength were on average 64-68% lower in the transverse vs. longitudinal beams (P<0.001, linear mixed model). Vascular porosity ranged between 3 and 42% of total bone volume. Longitudinal properties were associated negatively with porosity (P≤0.006, linear regressions). Mechanical properties, however, were not associated with osteocyte lacuna density or volumetric tissue mineral density (P≥0.167). Bone properties and structural parameters were not associated significantly with donor age (P≥0.225, linear mixed models). This study presents novel data regarding bone material strength in children with osteogenesis imperfecta. Results confirm that these properties are anisotropic. Elevated vascular porosity was observed in most specimens, and this parameter was associated with reduced bone material strength. These results offer insight toward understanding bone fragility and the role of intracortical porosity on the strength of bone tissue in children with osteogenesis imperfecta.
Author List
Albert C, Jameson J, Smith P, Harris GAuthor
Gerald Harris PhD Director in the Orthopaedic Research Engineering Center (OREC) department at Marquette UniversityMESH terms used to index this publication - Major topics in bold
AdolescentBiomechanical Phenomena
Bone and Bones
Child
Child, Preschool
Diaphyses
Elastic Modulus
Female
Humans
Imaging, Three-Dimensional
Linear Models
Male
Osteogenesis Imperfecta
Porosity
Tissue Donors
Weight-Bearing
X-Ray Microtomography