Dependences of the attenuation and the backscatter coefficients on the frequency, the bone volume fraction, and the trabecular thickness in trabecular-bone-mimicking phantoms

Background: Polymethyl methacrylate (PMMA) bone cement is widely used for osteoplasty. However, previous studies have demonstrated the adverse effects of PMMA due to its excessive stiffness and heat production. Recently, calcium phosphate cement (CPC) that overcomes those negative effects has been successfully applied in osteoplasty. The potential problem of CPC is markedly less initial stiffness. It leads to progressive, repeated collapse in the treated vertebra before CPC has been replaced by new bone that would provide substantial improvement in compressive strength and stiffness. The activated platelets in platelet-rich plasma (PRP) release a high concentration of growth factors which play an important role in bone healing. Objective: To investigate whether PRP could accelerate the osteoconduction of CPC and enhance the bone strength of the treated vertebra in an animal model. Study Design: Controlled animal study. Setting: Laboratory animal study, Methods: Thirty-two female Sprague-Dawley rats were ovariectomized at 8 weeks of age. After 3 months, they were randomly divided into 4 groups and received cement augmentation in the fifth caudal spine with different filler materials; sham-operated rats (S), PMMA (P), CPC (C), and CPC + PRP (CP). Bone mineral density (BMD) and trabecular type-associated morphological parameters, including trabecular bone volume fraction and trabecular thickness in the augmented caudal spine, were evaluated by micro-computed tomography (mirco-CT) 2 weeks after the cementoplasty. Histological analysis was also performed to compare the bone regeneration. Results: The trabecular bone volume fraction in the CP group was significantly greater than those of all the other groups. Trabecular thickness was higher in the CP group than the S and P groups. This augmented trabecular structure in the CP group accordingly showed higher BMD. Histological evaluations showed significantly more bone regeneration in the CP group. Limitations: There has been a concern that the effect of PRP would be dependent on the species, and might show different results in humans. Baseline values of micro-CT analysis were not measured, which could have provided exact evidence of the changes in trabecular microarchitecture parameters and cement resorption profiles. Finally, caudal vertebrae with filler materials used in biological study should have been compared by their mechanical properties using biomechanical evaluations for a more coherent study, which was not possible due to technical problems. Conclusions: Incorporating PRP into CPC could accelerate osteoconduction in the augmented vertebra leading to improvement of trabecular bone microarchitecture and BMD in rats. Key words: Bone mineral density, calcium phosphates, cementoplasty, histology, osteoconduction, osteoporosis, platelet-rich plasma, polymethyl methacrylate, vertebra

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Measurement of trabecular bone parameters with different bone thickness and voxel size in mice using micro CT

Malaysian Journal of Fundamental and Applied Sciences ◽

10.11113/mjfas.v15n2019.1128 ◽

2019 ◽

Vol 15 (1) ◽

pp. 65-68

Author(s):

Nurin Nadzlah Abu Bakar ◽

Basri Saidi ◽

Lyana Shahirah Mohamad Yamin

Keyword(s):

Trabecular Bone ◽

Volume Fraction ◽

Bone Volume ◽

Bone Morphology ◽

Bone Volume Fraction ◽

Voxel Size ◽

Trabecular Thickness ◽

Bone Parameters ◽

Trabecular Separation ◽

Trabecular Number

Micro-CT is one of the best modalities in assessing bone morphology and microarchitecture in small animal models. Voxel size is directly related to the image resolution as it influences the bone morphology results. The purpose of this study was to assess the effects of t different thicknesses of structures on the trabecular bone qualitative parameters. It was also to find out the most appropriate voxel size when scanning a certain or specific body part with different thicknesses. Five BALB-C breed mice carcasses were scanned using two different voxel sizes of 18 and 35 µm. The scanning acquisition times were recorded to be compared and the trabecular bone parameters measurements were taken. Both trabecular number and trabecular separation were increased in thicker structures meanwhile bone volume fraction and trabecular thickness values were inconsistent with the increment of the structure thickness. The bone volume fraction, trabecular thickness and trabecular separation were higher in larger voxel size and vice versa for trabecular number. The scanning acquisition time has no apparent correlation with the trabecular bone parameters. The thickness of the bone structure did affect trabecular number and trabecular separation significantly but less affecting bone volume fraction and trabecular thickness. All trabecular bone parameters were found affected by the size of scanning voxel size used. The usage of 35 µm voxel was more recommended than 18 µm to save time and give out less radiation dose to specimen unless the detailed features of the trabecular pattern was very important.

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Bone health in spacefaring rodents and primates: systematic review and meta-analysis

npj Microgravity ◽

10.1038/s41526-021-00147-7 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Jingyan Fu ◽

Matthew Goldsmith ◽

Sequoia D. Crooks ◽

Sean F. Condon ◽

Martin Morris ◽

...

Keyword(s):

Bone Formation ◽

Trabecular Bone ◽

Bone Health ◽

Volume Fraction ◽

Meta Analysis ◽

Bone Volume ◽

Trabecular Bone Volume ◽

Bone Volume Fraction ◽

Percentage Difference ◽

Induced Changes

AbstractAnimals in space exploration studies serve both as a model for human physiology and as a means to understand the physiological effects of microgravity. To quantify the microgravity-induced changes to bone health in animals, we systematically searched Medline, Embase, Web of Science, BIOSIS, and NASA Technical reports. We selected 40 papers focusing on the bone health of 95 rats, 61 mice, and 9 rhesus monkeys from 22 space missions. The percentage difference from ground control in rodents was –24.1% [Confidence interval: −43.4, −4.9] for trabecular bone volume fraction and –5.9% [−8.0, −3.8] for the cortical area. In primates, trabecular bone volume fraction was lower by –25.2% [−35.6, −14.7] in spaceflight animals compared to GC. Bone formation indices in rodent trabecular and cortical bone were significantly lower in microgravity. In contrast, osteoclast numbers were not affected in rats and were variably affected in mice. Thus, microgravity induces bone deficits in rodents and primates likely through the suppression of bone formation.

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Biaxial Normal Strength Behavior in the Axial-Transverse Plane for Human Trabecular Bone—Effects of Bone Volume Fraction, Microarchitecture, and Anisotropy

Journal of Biomechanical Engineering ◽

10.1115/1.4025679 ◽

2013 ◽

Vol 135 (12) ◽

Cited By ~ 5

Author(s):

Arnav Sanyal ◽

Tony M. Keaveny

Keyword(s):

Trabecular Bone ◽

Volume Fraction ◽

Elastic Anisotropy ◽

Bone Volume ◽

Transverse Plane ◽

Mechanical Anisotropy ◽

Bone Volume Fraction ◽

Human Trabecular Bone ◽

Strength Behavior ◽

Normal Strength

The biaxial failure behavior of the human trabecular bone, which has potential relevance both for fall and gait loading conditions, is not well understood, particularly for low-density bone, which can display considerable mechanical anisotropy. Addressing this issue, we investigated the biaxial normal strength behavior and the underlying failure mechanisms for human trabecular bone displaying a wide range of bone volume fraction (0.06–0.34) and elastic anisotropy. Micro-computed tomography (CT)-based nonlinear finite element analysis was used to simulate biaxial failure in 15 specimens (5 mm cubes), spanning the complete biaxial normal stress failure space in the axial-transverse plane. The specimens, treated as approximately transversely isotropic, were loaded in the principal material orientation. We found that the biaxial stress yield surface was well characterized by the superposition of two ellipses—one each for yield failure in the longitudinal and transverse loading directions—and the size, shape, and orientation of which depended on bone volume fraction and elastic anisotropy. However, when normalized by the uniaxial tensile and compressive strengths in the longitudinal and transverse directions, all of which depended on bone volume fraction, microarchitecture, and mechanical anisotropy, the resulting normalized biaxial strength behavior was well described by a single pair of (longitudinal and transverse) ellipses, with little interspecimen variation. Taken together, these results indicate that the role of bone volume fraction, microarchitecture, and mechanical anisotropy is mostly accounted for in determining the uniaxial strength behavior and the effect of these parameters on the axial-transverse biaxial normal strength behavior per se is minor.

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Non-Invasive Analysis of the Micro-Structural and Biomechanical Properties of Trabecular Bone in Human Femoral Head

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.321-323.1070 ◽

2006 ◽

Vol 321-323 ◽

pp. 1070-1073

Author(s):

Ye Yeon Won ◽

Myong Hyun Baek ◽

Wen Quan Cui ◽

Kwang Kyun Kim

Keyword(s):

Mechanical Properties ◽

Mechanical Property ◽

Femoral Head ◽

Trabecular Bone ◽

Volume Fraction ◽

Reaction Force ◽

Bone Volume ◽

Fe Model ◽

Micro Ct ◽

Trabecular Thickness

This study investigates micro-structural and mechanical properties of trabecular bone in human femoral head with and without osteoporosis using a micro-CT and a finite element model. 15 cored trabecular bone specimens with 20 of diameter were obtained from femoral heads with osteoporosis resected for total hip arthroplasty, and 5 specimens were removed from femoral head of cadavers, which has no history of musculoskeletal diseases. A high-resolution micro-CT system was used to scan each specimen to obtain histomorphometry indexes. Based on the micro-images, a FE-model was created to determine mechanical property indexes. While the non-osteoporosis group had increases the trabecular thickness, the bone volume, the bone volume fraction, the degree of anisotropy and the trabecular number compared with those of osteoporotic group, the non-osteoporotic group showed decreases in trabecular separation and structure model index. Regarding the mechanical property indexes, the reaction force and the Young's modulus were lower in the osteoporotic group than in non-osteoporotic group. Our data shows salient deteriorations in trabecular micro-structural and mechanical properties in human femoral head with osteoporosis.

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Architectural changes of trabecular bone caused by the remodeling process

MRS Proceedings ◽

10.1557/proc-874-l1.9 ◽

2005 ◽

Vol 874 ◽

Author(s):

Richard Weinkamer ◽

Markus A. Hartmann ◽

Yves Brechet ◽

Peter Fratzl

Keyword(s):

Trabecular Bone ◽

Feedback Loop ◽

Mechanical Response ◽

Volume Fraction ◽

Bone Volume ◽

Bone Architecture ◽

Mechanical Problem ◽

Bone Volume Fraction ◽

Obvious Effect ◽

Trabecular Bone Architecture

AbstractUsing a stochastic lattice model we have studied the architectural changes of trabecular bone occurring while the structure is remodeled. Our model considers the mechanical feedback loop, which control the remodeling process. A fast algorithm was employed to solve approximately the mechanical problem. A general feature of the model is that a networklike structure emerges, which further coarsens while the bone volume fraction remains unchanged. Decreasing the mechanical response of the system by either lowering the external load or the internal mechano-sensitivity leads not only to a reduction of the bone volume fraction, but results in topological changes of the trabecular bone architecture, where the loss of horizontal trabeculae is the most obvious effect.

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The plate-to-rod transition in trabecular bone loss is elusive

Royal Society Open Science ◽

10.1098/rsos.201401 ◽

2021 ◽

Vol 8 (6) ◽

pp. 201401

Author(s):

A. A. Felder ◽

S. Monzem ◽

R. De Souza ◽

B. Javaheri ◽

D. Mills ◽

...

Keyword(s):

Bone Loss ◽

Trabecular Bone ◽

Volume Fraction ◽

Bone Volume ◽

Continuous Measure ◽

Bone Volume Fraction ◽

Trabecular Bone Loss ◽

Mouse Tibia ◽

Disease Stages ◽

The Relationship

Changes in trabecular micro-architecture are key to our understanding of osteoporosis. Previous work focusing on structure model index (SMI) measurements have concluded that disease progression entails a shift from plates to rods in trabecular bone, but SMI is heavily biased by bone volume fraction. As an alternative to SMI, we proposed the ellipsoid factor (EF) as a continuous measure of local trabecular shape between plate-like and rod-like extremes. We investigated the relationship between EF distributions, SMI and bone volume fraction of the trabecular geometry in a murine model of disuse osteoporosis as well as from human vertebrae of differing bone volume fraction. We observed a moderate shift in EF median (at later disease stages in mouse tibia) and EF mode (in the vertebral samples with low bone volume fraction) towards a more rod-like geometry, but not in EF maximum and minimum. These results support the notion that the plate to rod transition does not coincide with the onset of bone loss and is considerably more moderate, when it does occur, than SMI suggests. A variety of local shapes not straightforward to categorize as rod or plate exist in all our trabecular bone samples.

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Bone and muscle development in three inbred female mouse strains

Osteologie/Osteology ◽

10.1055/a-1287-6016 ◽

2021 ◽

Author(s):

Ursula Föger-Samwald ◽

Maria Papageorgiou ◽

Katharina Wahl-Figlash ◽

Katharina Kerschan-Schindl ◽

Peter Pietschmann

Keyword(s):

Trabecular Bone ◽

Muscle Development ◽

Bone Growth ◽

Volume Fraction ◽

Bone Structure ◽

Bone Development ◽

Mouse Strains ◽

Structural Reorganization ◽

Bone Volume Fraction ◽

Trabecular Thickness

AbstractMuscle force is thought to be one of the main determinants of bone development. Hence, peak muscle growth is expected to precede peak bone growth. In this study, we investigated muscle and bone development in female C57BL/6 J, DBA/2JRj, and C3H/HeOuJ mice. Femoral cortical and trabecular bone structure and the weights of selected muscles were assessed at the ages of 8, 16, and 24 weeks. Muscle mass increased from 8 to 24 weeks in all 3 strains, suggesting peak muscle development at 24 weeks or later. Bone volume fraction, trabecular number, and connectivity density of the femur decreased or remained unchanged, whereas trabecular density and trabecular thickness largely increased. These results suggest a peak in trabecular bone accrual at 8 weeks or earlier followed by further increases in density and structural reorganization of trabeculae. Cortical density, cortical thickness, and cortical cross sectional area increased over time, suggesting a peak in cortical bone accrual at 24 weeks or later. In conclusion, our data provide evidence that growth of muscle lags behind trabecular bone accrual.

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