Mechanical property and tissue mineral density differences among severely suppressed bone turnover (SSBT) patients, osteoporotic patients, and normal subjects

Crystal K. Tjhia, Clarita V. Odvina, D. Sudhaker Rao, Susan M Stover, Xiang Wang, David P Fyhrie

Research output: Contribution to journalArticle

40 Citations (Scopus)

Abstract

Pathogenesis of atypical fractures in patients on long term bisphosphonate therapy is poorly understood, and the type, the manner in which they occur and the fracture sites are quite different from the usual osteoporotic fractures. We hypothesized that the tissue-level mechanical properties and mean degree of mineralization of the iliac bone would differ among 1) patients with atypical fractures and severely suppressed bone turnover (SSBT) associated with long-term bisphosphonate therapy, 2) age-matched, treatment-naïve osteoporotic patients with vertebral fracture, 3) age-matched normals and 4) young normals. Large differences in tissue-level mechanical properties and/or mineralization among these groups could help explain the underlying mechanism(s) for the occurrence of typical osteoporotic and the atypical femoral shaft fractures. Elastic modulus, contact hardness, plastic deformation resistance, and tissue mineral densities of cortical and trabecular bone regions of 55 iliac bone biopsies-12 SSBT patients (SSBT; aged 49-77), 11 age-matched untreated osteoporotic patients with vertebral fracture (Osteoporotic), 12 age-matched subjects without bone fracture (Age-Matched Normal), and 20 younger subjects without bone fracture (Young Normal)-were measured using nanoindentation and quantitative backscattered electron microscopy. For cortical bone nanoindentation properties, only plastic deformation resistance was different among the groups (p< 0.05), with greater resistance to plastic deformation in the SSBT group compared to all other groups. For trabecular bone, all nanoindentation properties and mineral density of the trabecular bone were different among the groups (p< 0.05). The SSBT group had greater plastic deformation resistance and harder trabecular bone compared to the other three groups, stiffer bone compared to the Osteoporotic and Young Normal groups, and a trend of higher mineral density compared to the Age-Matched Normal and Osteoporotic groups. Lower heterogeneity of modulus and contact hardness for cortical bone of the SSBT and trabecular bone of the Osteoporotic fracture groups, respectively, compared to the non-fractured groups, may contribute to fracture susceptibility due to lowered ability to prevent crack propagation. We tentatively conclude that, in addition to extremely low bone formation rate, atypical fractures in SSBT and/or long-term bisphosphonate treatment may be associated with greater mean plastic deformation resistance properties and less heterogeneous elastic properties of the bone.

Original languageEnglish (US)
Pages (from-to)1279-1289
Number of pages11
JournalBone
Volume49
Issue number6
DOIs
StatePublished - Dec 2011

Fingerprint

Bone Remodeling
Minerals
Plastics
Osteoporotic Fractures
Bone Fractures
Diphosphonates
Bone and Bones
Hardness
Physiologic Calcification
Femoral Fractures
Elastic Modulus
Therapeutics
Osteogenesis
Electron Microscopy
Cancellous Bone
Biopsy
Cortical Bone

Keywords

  • Atypical fracture
  • Bisphosphonate
  • Mechanical properties
  • Mineral density
  • Nanoindentation
  • Severely suppressed bone turnover

ASJC Scopus subject areas

  • Physiology
  • Endocrinology, Diabetes and Metabolism
  • Histology

Cite this

Mechanical property and tissue mineral density differences among severely suppressed bone turnover (SSBT) patients, osteoporotic patients, and normal subjects. / Tjhia, Crystal K.; Odvina, Clarita V.; Rao, D. Sudhaker; Stover, Susan M; Wang, Xiang; Fyhrie, David P.

In: Bone, Vol. 49, No. 6, 12.2011, p. 1279-1289.

Research output: Contribution to journalArticle

@article{e81b4fdaf7da478999cca4a7a99af0be,
title = "Mechanical property and tissue mineral density differences among severely suppressed bone turnover (SSBT) patients, osteoporotic patients, and normal subjects",
abstract = "Pathogenesis of atypical fractures in patients on long term bisphosphonate therapy is poorly understood, and the type, the manner in which they occur and the fracture sites are quite different from the usual osteoporotic fractures. We hypothesized that the tissue-level mechanical properties and mean degree of mineralization of the iliac bone would differ among 1) patients with atypical fractures and severely suppressed bone turnover (SSBT) associated with long-term bisphosphonate therapy, 2) age-matched, treatment-na{\"i}ve osteoporotic patients with vertebral fracture, 3) age-matched normals and 4) young normals. Large differences in tissue-level mechanical properties and/or mineralization among these groups could help explain the underlying mechanism(s) for the occurrence of typical osteoporotic and the atypical femoral shaft fractures. Elastic modulus, contact hardness, plastic deformation resistance, and tissue mineral densities of cortical and trabecular bone regions of 55 iliac bone biopsies-12 SSBT patients (SSBT; aged 49-77), 11 age-matched untreated osteoporotic patients with vertebral fracture (Osteoporotic), 12 age-matched subjects without bone fracture (Age-Matched Normal), and 20 younger subjects without bone fracture (Young Normal)-were measured using nanoindentation and quantitative backscattered electron microscopy. For cortical bone nanoindentation properties, only plastic deformation resistance was different among the groups (p< 0.05), with greater resistance to plastic deformation in the SSBT group compared to all other groups. For trabecular bone, all nanoindentation properties and mineral density of the trabecular bone were different among the groups (p< 0.05). The SSBT group had greater plastic deformation resistance and harder trabecular bone compared to the other three groups, stiffer bone compared to the Osteoporotic and Young Normal groups, and a trend of higher mineral density compared to the Age-Matched Normal and Osteoporotic groups. Lower heterogeneity of modulus and contact hardness for cortical bone of the SSBT and trabecular bone of the Osteoporotic fracture groups, respectively, compared to the non-fractured groups, may contribute to fracture susceptibility due to lowered ability to prevent crack propagation. We tentatively conclude that, in addition to extremely low bone formation rate, atypical fractures in SSBT and/or long-term bisphosphonate treatment may be associated with greater mean plastic deformation resistance properties and less heterogeneous elastic properties of the bone.",
keywords = "Atypical fracture, Bisphosphonate, Mechanical properties, Mineral density, Nanoindentation, Severely suppressed bone turnover",
author = "Tjhia, {Crystal K.} and Odvina, {Clarita V.} and Rao, {D. Sudhaker} and Stover, {Susan M} and Xiang Wang and Fyhrie, {David P}",
year = "2011",
month = "12",
doi = "10.1016/j.bone.2011.09.042",
language = "English (US)",
volume = "49",
pages = "1279--1289",
journal = "Bone",
issn = "8756-3282",
publisher = "Elsevier Inc.",
number = "6",

}

TY - JOUR

T1 - Mechanical property and tissue mineral density differences among severely suppressed bone turnover (SSBT) patients, osteoporotic patients, and normal subjects

AU - Tjhia, Crystal K.

AU - Odvina, Clarita V.

AU - Rao, D. Sudhaker

AU - Stover, Susan M

AU - Wang, Xiang

AU - Fyhrie, David P

PY - 2011/12

Y1 - 2011/12

N2 - Pathogenesis of atypical fractures in patients on long term bisphosphonate therapy is poorly understood, and the type, the manner in which they occur and the fracture sites are quite different from the usual osteoporotic fractures. We hypothesized that the tissue-level mechanical properties and mean degree of mineralization of the iliac bone would differ among 1) patients with atypical fractures and severely suppressed bone turnover (SSBT) associated with long-term bisphosphonate therapy, 2) age-matched, treatment-naïve osteoporotic patients with vertebral fracture, 3) age-matched normals and 4) young normals. Large differences in tissue-level mechanical properties and/or mineralization among these groups could help explain the underlying mechanism(s) for the occurrence of typical osteoporotic and the atypical femoral shaft fractures. Elastic modulus, contact hardness, plastic deformation resistance, and tissue mineral densities of cortical and trabecular bone regions of 55 iliac bone biopsies-12 SSBT patients (SSBT; aged 49-77), 11 age-matched untreated osteoporotic patients with vertebral fracture (Osteoporotic), 12 age-matched subjects without bone fracture (Age-Matched Normal), and 20 younger subjects without bone fracture (Young Normal)-were measured using nanoindentation and quantitative backscattered electron microscopy. For cortical bone nanoindentation properties, only plastic deformation resistance was different among the groups (p< 0.05), with greater resistance to plastic deformation in the SSBT group compared to all other groups. For trabecular bone, all nanoindentation properties and mineral density of the trabecular bone were different among the groups (p< 0.05). The SSBT group had greater plastic deformation resistance and harder trabecular bone compared to the other three groups, stiffer bone compared to the Osteoporotic and Young Normal groups, and a trend of higher mineral density compared to the Age-Matched Normal and Osteoporotic groups. Lower heterogeneity of modulus and contact hardness for cortical bone of the SSBT and trabecular bone of the Osteoporotic fracture groups, respectively, compared to the non-fractured groups, may contribute to fracture susceptibility due to lowered ability to prevent crack propagation. We tentatively conclude that, in addition to extremely low bone formation rate, atypical fractures in SSBT and/or long-term bisphosphonate treatment may be associated with greater mean plastic deformation resistance properties and less heterogeneous elastic properties of the bone.

AB - Pathogenesis of atypical fractures in patients on long term bisphosphonate therapy is poorly understood, and the type, the manner in which they occur and the fracture sites are quite different from the usual osteoporotic fractures. We hypothesized that the tissue-level mechanical properties and mean degree of mineralization of the iliac bone would differ among 1) patients with atypical fractures and severely suppressed bone turnover (SSBT) associated with long-term bisphosphonate therapy, 2) age-matched, treatment-naïve osteoporotic patients with vertebral fracture, 3) age-matched normals and 4) young normals. Large differences in tissue-level mechanical properties and/or mineralization among these groups could help explain the underlying mechanism(s) for the occurrence of typical osteoporotic and the atypical femoral shaft fractures. Elastic modulus, contact hardness, plastic deformation resistance, and tissue mineral densities of cortical and trabecular bone regions of 55 iliac bone biopsies-12 SSBT patients (SSBT; aged 49-77), 11 age-matched untreated osteoporotic patients with vertebral fracture (Osteoporotic), 12 age-matched subjects without bone fracture (Age-Matched Normal), and 20 younger subjects without bone fracture (Young Normal)-were measured using nanoindentation and quantitative backscattered electron microscopy. For cortical bone nanoindentation properties, only plastic deformation resistance was different among the groups (p< 0.05), with greater resistance to plastic deformation in the SSBT group compared to all other groups. For trabecular bone, all nanoindentation properties and mineral density of the trabecular bone were different among the groups (p< 0.05). The SSBT group had greater plastic deformation resistance and harder trabecular bone compared to the other three groups, stiffer bone compared to the Osteoporotic and Young Normal groups, and a trend of higher mineral density compared to the Age-Matched Normal and Osteoporotic groups. Lower heterogeneity of modulus and contact hardness for cortical bone of the SSBT and trabecular bone of the Osteoporotic fracture groups, respectively, compared to the non-fractured groups, may contribute to fracture susceptibility due to lowered ability to prevent crack propagation. We tentatively conclude that, in addition to extremely low bone formation rate, atypical fractures in SSBT and/or long-term bisphosphonate treatment may be associated with greater mean plastic deformation resistance properties and less heterogeneous elastic properties of the bone.

KW - Atypical fracture

KW - Bisphosphonate

KW - Mechanical properties

KW - Mineral density

KW - Nanoindentation

KW - Severely suppressed bone turnover

UR - http://www.scopus.com/inward/record.url?scp=81355160420&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=81355160420&partnerID=8YFLogxK

U2 - 10.1016/j.bone.2011.09.042

DO - 10.1016/j.bone.2011.09.042

M3 - Article

VL - 49

SP - 1279

EP - 1289

JO - Bone

JF - Bone

SN - 8756-3282

IS - 6

ER -