Effects of Once-Weekly Teriparatide Treatment on Trabecular Bone Microdamage Accumulation and Cortical Structure in the Lumbar Vertebrae of Ovariectomized Cynomolgus Monkeys

Several approaches (anterior, posterior, lateral, and transforaminal) are used in lumbar fusion surgery. However, it is unclear whether one of these approaches has the greatest subsidence risk as published clinical rates of cage subsidence vary widely (7–70%). Specifically, there is limited data on how a patient's endplate morphometry and trabecular bone quality influences cage subsidence risk. Therefore, this study compared subsidence (stiffness, maximum force, and work) between anterior (ALIF), lateral (LLIF), posterior (PLIF), and transforaminal (TLIF) lumbar interbody fusion cage designs to understand the impact of endplate and trabecular bone quality on subsidence. Forty-eight lumbar vertebrae were imaged with micro-ct to assess trabecular microarchitecture. micro-ct images of each vertebra were then imported into image processing software to measure endplate thickness (ET) and maximum endplate concavity depth (ECD). Generic ALIF, LLIF, PLIF, and TLIF cages made of polyether ether ketone were implanted on the superior endplates of all vertebrae and subsidence testing was performed. The results indicated that TLIF cages had significantly lower (p < 0.01) subsidence stiffness and maximum subsidence force compared to ALIF and LLIF cages. For all cage groups, trabecular bone volume fraction was better correlated with maximum subsidence force compared to ET and concavity depth. These findings highlight the importance of cage design (e.g., surface area), placement on the endplate, and trabecular bone quality on subsidence. These results may help surgeons during cage selection for lumbar fusion procedures to mitigate adverse events such as cage subsidence.

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Age Related Lumbar Trabecular Bone in a Thai Population

Chiang Mai University Journal of Natural Sciences ◽

10.12982/cmujns.2021.069 ◽

2021 ◽

Vol 20 (3) ◽

Author(s):

Pornpath Sattarath ◽

Kittichai Wantanajittikul ◽

Sukon Prasitwattanaseree ◽

Jongkolnee Settakorn ◽

Karnda Mekjaidee

Keyword(s):

Trabecular Bone ◽

Negative Correlation ◽

Spinal Column ◽

Lumbar Vertebrae ◽

Processing Technique ◽

Image Processing Technique ◽

Female Group ◽

Thai Population ◽

Age Related ◽

The Individual

Within spinal column, the lumbar vertebrae are the most durable and usually left behind in severely burnt body. European studies have reported that these vertebrae are useful for age estimation. However, it is widely acknowledged that different ancestry necessitates different methods and includes a range of variables, therefore a study specific to Thai population is needed for accuracy in the identification of Thai individuals. To investigate the correlation between lumbar vertebrae, and age of the individual, L1-L5 drilled out from 75 Thai cadavers. After undergoing histological processing each slide was photographed. The images were processed using an image processing technique to calculate the percentage of trabecular bone area over total area (%TBA/TA). Using the Statistical Package for the Social Sciences (SPSS) program, %TBA/TA of L1-L5 was calculated. The %TBA/TA of L1-L5 showed a negative correlation to age in both male and female groups. The %TBA/TA of L2 in the male group decreased most significantly with increase in age (r=-0.775) whereas in the female group, L3 showed the strongest negative correlation with age (r=-0.75. In the conclusion, it was found that trabecular bone of L2 showed the most significant correlation to increase in age in males whereas L3 showed the strongest correlation in females. Keywords: Age, Image segmentation, Lumbar, Thai population, Trabecular bone

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The Effect of Number of Cycles on Microdamage Accumulation in Bovine Trabecular Bone

10.1115/imece2001/bed-23026 ◽

2001 ◽

Author(s):

Tara L. Arthur Moore ◽

Lorna J. Gibson

Keyword(s):

Trabecular Bone ◽

Bone Remodeling ◽

Low Cycle Fatigue ◽

Cycle Fatigue ◽

Repetitive Motion ◽

Microdamage Accumulation ◽

Lower Load ◽

Small Cracks ◽

Number Of Cycles ◽

Fatigue Microdamage

Abstract Microdamage, in the form of small cracks, exists in healthy bone. Microdamage can be created by an overload or by repetitive motion (fatigue) during daily activities. Usually, microdamage is repaired during bone remodeling and a steady state is maintained. However, in cases of excessive microdamage creation or slowed bone remodeling, microdamage can coalesce to create a fracture. Our previous work [1,2] has investigated microdamage accumulation with increasing strain in bovine trabecular bone loaded in monotonic compression and compressive fatigue. Specimens fatigued at relatively high load levels fail after a few loading cycles, while specimens fatigued at lower load levels may undergo thousands of cycles before failure. During high cycle fatigue, microdamage may accumulate by the growth of pre-existing microcracks, as well as by the crack initiation seen in low cycle fatigue.

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Fracture Mechanics of Architecture Dependent Fracture in Trabecular Bone Using the Cohesive Finite Element Method

ASME 2007 Summer Bioengineering Conference ◽

10.1115/sbc2007-176072 ◽

2007 ◽

Author(s):

Vikas Tomar

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Trabecular Bone ◽

Fracture Behavior ◽

Bone Microstructure ◽

Tissue Properties ◽

Rate Dependent ◽

Microdamage Accumulation ◽

Element Method ◽

Rate Of Loading

Trabecular bone fracture is closely related to the trabecular architecture and microdamage accumulation. Micro-finite element models have been used to investigate the elastic and yield properties of trabecular bone but have only seen limited application in modeling the microstructure dependent fracture of trabecular bone, [1, 2]. In the presented research a cohesive finite element method (CFEM) based approach that can be used to model microstructure and loading rate dependent fracture in trabecular bone is developed for the first time. The emphasis is on understanding the effect of the rate of loading and its correlation with the bone microstructure on the microdamage accumulation and fracture behavior in the trabecular bone. Analyses focus on understanding the effect of the rate of loading, change in bone tissue properties with aging, and their correlation with the bone microstructure on the microdamage accumulation and the fracture behavior in the trabecular bone.

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A Methodology for Mechanical Measurements of Technical Constants of Trabecular Bone

Engineering in Medicine ◽

10.1243/emed_jour_1988_017_044_02 ◽

1988 ◽

Vol 17 (4) ◽

pp. 169-173 ◽

Cited By ~ 8

Author(s):

L H Yahia ◽

G Drouin ◽

P Duval

Keyword(s):

Trabecular Bone ◽

Three Dimensional ◽

Lumbar Vertebrae ◽

Bony Tissue ◽

Ultrasonic Methods ◽

Vertebral Trabecular Bone ◽

Young’S Moduli ◽

Orthotropic Properties ◽

First Time ◽

Non Destructive

Vertebral trabecular bone was tested by non-destructive uniaxial and triaxial loadings with the purpose of investigating the orthotropic properties of bone. A triaxial testing apparatus using hydrostatic pressure was developed and allowed to characterise the bony tissue in a three-dimensional stressed state. Thirty specimens, in the form of 10 mm cubes, were tested. The Young's moduli obtained in this study for the trabecular bone of human lumbar vertebrae are found to be in agreement with the values obtained by ultrasonic methods. Analyses of triaxial compressive tests provided, for the first time, the Poisson's ratios of vertebral trabecular bone. These values are found to satisfy thermodynamic restrictions established by Cowin and Van Buskirk (1986). Finally, no significant differences in the material properties were found for segment level (L3-L4).

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