Article

Osteogenesis imperfecta is a heterogeneous genetic disorder
characterized by bone fragility. Previous research suggests that impaired
collagen network and abnormal mineralization affect bone tissue properties,
however, little data is yet available to describe bone material properties in
individuals with this disorder. Bone material properties have not been
characterized in individuals with the most common form of osteogenesis
imperfecta, type I. METHODS: Bone tissue elastic modulus and hardness were
measured by nanoindentation in eleven osteotomy specimens that were harvested
from children with osteogenesis imperfecta during routine surgeries. These
properties were compared between osteogenesis imperfecta types I (mild, n=6) and
III (severe, n=5), as well as between interstitial and osteonal microstructural
regions using linear mixed model analysis. FINDINGS: Disease severity type had a
small but statistically significant effect on modulus (7%, P=0.02) and hardness
(8%, P<0.01). Individuals with osteogenesis imperfecta type I had higher modulus
and hardness than did those with type III. Overall, mean modulus and hardness
values were 13% greater in interstitial lamellar bone regions than in osteonal
regions (P<0.001). INTERPRETATION: The current study presents the first dataset
describing bone material properties in individuals with the most common form of
osteogenesis imperfecta, i.e., type I. Results indicate that intrinsic bone
tissue properties are affected by phenotype. Knowledge of the material properties
of bones in osteogenesis imperfecta will contribute to the ability to develop
models to assist in predicting fracture risk.
CI - Copyright (c) 2012 Elsevier Ltd. All rights reserved.

Langue : ANGLAIS