Micro-morphological properties of osteons reveal changes in cortical bone stability during aging, osteoporosis, and bisphosphonate treatment in women

TY - JOUR

T1 - Micro-morphological properties of osteons reveal changes in cortical bone stability during aging, osteoporosis, and bisphosphonate treatment in women

AU - Bernhard, Andreas

AU - Milovanovic, P

AU - Zimmermann, E A

AU - Hahn, M

AU - Djonic, D

AU - Krause, M

AU - Breer, S

AU - Püschel, K

AU - Djuric, M

AU - Amling, M

AU - Busse, B

PY - 2013/10/1

Y1 - 2013/10/1

N2 - SUMMARY: We analyzed morphological characteristics of osteons along with the geometrical indices of individual osteonal mechanical stability in young, healthy aged, untreated osteoporotic, and bisphosphonate-treated osteoporotic women. Our study revealed significant intergroup differences in osteonal morphology and osteocyte lacunae indicating different remodeling patterns with implications for fracture susceptibility.INTRODUCTION: Bone remodeling is the key process in bone structural reorganization, and its alterations lead to changes in bone mechanical strength. Since osteons reflect different bone remodeling patterns, we hypothesize that the femoral cortices of females under miscellaneous age, disease and treatment conditions will display distinct osteonal morphology and osteocyte lacunar numbers along with different mechanical properties.METHODS: The specimens used in this study were collected at autopsy from 35 female donors (young group, n = 6, age 32 ± 8 years; aged group, n = 10, age 79 ± 9 years; osteoporosis group, n = 10, age 81 ± 9 years; and bisphosphonate group, n = 9, age 81 ± 7 years). Von Kossa-modified stained femoral proximal diaphyseal sections were evaluated for osteonal morphometric parameters and osteocyte lacunar data. Geometrical indices of osteonal cross-sections were calculated to assess the mechanical stability of individual osteons, in terms of their resistance to compression, bending, and buckling.RESULTS: The morphological assessment of osteons and quantification of their osteocyte lacunae revealed significant differences between the young, aged, osteoporosis and bisphosphonate-treated groups. Calculated osteonal geometric indices provided estimates of the individual osteons' resistance to compression, bending and buckling based on their size. In particular, the osteons in the bisphosphonate-treated group presented improved osteonal geometry along with increased numbers of osteocyte lacunae that had been formerly impaired due to aging and osteoporosis.CONCLUSIONS: The data derived from osteons (as the basic structural units of the cortical bone) in different skeletal conditions can be employed to highlight structural factors contributing to the fracture susceptibility of various groups of individuals.

AB - SUMMARY: We analyzed morphological characteristics of osteons along with the geometrical indices of individual osteonal mechanical stability in young, healthy aged, untreated osteoporotic, and bisphosphonate-treated osteoporotic women. Our study revealed significant intergroup differences in osteonal morphology and osteocyte lacunae indicating different remodeling patterns with implications for fracture susceptibility.INTRODUCTION: Bone remodeling is the key process in bone structural reorganization, and its alterations lead to changes in bone mechanical strength. Since osteons reflect different bone remodeling patterns, we hypothesize that the femoral cortices of females under miscellaneous age, disease and treatment conditions will display distinct osteonal morphology and osteocyte lacunar numbers along with different mechanical properties.METHODS: The specimens used in this study were collected at autopsy from 35 female donors (young group, n = 6, age 32 ± 8 years; aged group, n = 10, age 79 ± 9 years; osteoporosis group, n = 10, age 81 ± 9 years; and bisphosphonate group, n = 9, age 81 ± 7 years). Von Kossa-modified stained femoral proximal diaphyseal sections were evaluated for osteonal morphometric parameters and osteocyte lacunar data. Geometrical indices of osteonal cross-sections were calculated to assess the mechanical stability of individual osteons, in terms of their resistance to compression, bending, and buckling.RESULTS: The morphological assessment of osteons and quantification of their osteocyte lacunae revealed significant differences between the young, aged, osteoporosis and bisphosphonate-treated groups. Calculated osteonal geometric indices provided estimates of the individual osteons' resistance to compression, bending and buckling based on their size. In particular, the osteons in the bisphosphonate-treated group presented improved osteonal geometry along with increased numbers of osteocyte lacunae that had been formerly impaired due to aging and osteoporosis.CONCLUSIONS: The data derived from osteons (as the basic structural units of the cortical bone) in different skeletal conditions can be employed to highlight structural factors contributing to the fracture susceptibility of various groups of individuals.

KW - Adult

KW - Aged

KW - Aged, 80 and over

KW - Aging

KW - Bone Density Conservation Agents

KW - Bone Remodeling

KW - Diphosphonates

KW - Female

KW - Femur

KW - Haversian System

KW - Humans

KW - Osteocytes

KW - Osteoporosis, Postmenopausal

KW - Specimen Handling

KW - Stress, Mechanical

U2 - 10.1007/s00198-013-2374-x

DO - 10.1007/s00198-013-2374-x

M3 - SCORING: Journal article

C2 - 23632826

VL - 24

SP - 2671

EP - 2680

JO - OSTEOPOROSIS INT

JF - OSTEOPOROSIS INT

SN - 0937-941X

IS - 10

ER -