Risk of fracture in elderly patients: a new predictive index based on bone mineral density and finite element analysis

A biomechanical test is a good evaluation method that describes the structural, functional, and pathological differences in the bones, such as osteoporosis and fracture. The tensile test, compression test, and bending test are generally performed to evaluate the elastic modulus of the bone using mice. In particular, the femoral head compression test is mainly used for verifying the osteoporosis change of the femoral neck. This study conducted bone mineral density analysis using in vivo microcomputed tomography (micro-CT) to observe changes in osteoporosis over time. It proposed a method of identifying the elastic modulus of the femur in the normal group (CON group) and the osteoporotic group (OVX group) through finite element analysis based on the femoral head compression test and also conducted a comparative analysis of the results. Through the femoral head compression test, it was verified that the CON group’s ultimate and yield loads were significantly higher than those of the OVX group. It was considered that this result was caused by the fact that the bone mineral density change by osteoporosis occurred in the proximal end more often than in the femur diaphysis. However, the elastic modulus derived from the finite element analysis showed no significant difference between the two groups.

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Alterations of bone mineral density, bone microarchitecture and strength in patients with ankylosing spondylitis: a cross-sectional study using high-resolution peripheral quantitative computerized tomography and finite element analysis

Arthritis Research & Therapy ◽

10.1186/s13075-015-0873-1 ◽

2015 ◽

Vol 17 (1) ◽

Cited By ~ 18

Author(s):

Nisha Nigil Haroon ◽

Eva Szabo ◽

Janet M. Raboud ◽

Heather Mcdonald-Blumer ◽

Lydia Fung ◽

...

Keyword(s):

Bone Mineral Density ◽

Finite Element Analysis ◽

Finite Element ◽

Bone Microarchitecture ◽

Cross Sectional Study ◽

Sectional Study ◽

Mineral Density ◽

Element Analysis ◽

Cross Sectional ◽

Quantitative Computerized Tomography

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Patient-Specific Phantomless Estimation of Bone Mineral Density and Its Effects on Finite Element Analysis Results: A Feasibility Study

Computational and Mathematical Methods in Medicine ◽

10.1155/2019/4102410 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

Young Han Lee ◽

Jung Jin Kim ◽

In Gwun Jang

Keyword(s):

Bone Mineral Density ◽

Finite Element Analysis ◽

Finite Element ◽

Lumbar Spine ◽

Regression Model ◽

Proximal Femur ◽

Strain Energy ◽

Mineral Density ◽

Element Analysis ◽

Reference Phantom

Objectives. This study proposes a regression model for the phantomless Hounsfield units (HU) to bone mineral density (BMD) conversion including patient physical factors and analyzes the accuracy of the estimated BMD values. Methods. The HU values, BMDs, circumferences of the body, and cross-sectional areas of bone were measured from 39 quantitative computed tomography images of L2 vertebrae and hips. Then, the phantomless HU-to-BMD conversion was derived using a multiple linear regression model. For the statistical analysis, the correlation between the estimated BMD values and the reference BMD values was evaluated using Pearson’s correlation test. Voxelwise BMD and finite element analysis (FEA) results were analyzed in terms of root-mean-square error (RMSE) and strain energy density, respectively. Results. The HU values and circumferences were statistically significant (p<0.05) for the lumbar spine, whereas only the HU values were statistically significant (p<0.05) for the proximal femur. The BMD values estimated using the proposed HU-to-BMD conversion were significantly correlated with those measured using the reference phantom: Pearson’s correlation coefficients of 0.998 and 0.984 for the lumbar spine and proximal femur, respectively. The RMSEs of the estimated BMD values for the lumbar spine and hip were 4.26 ± 0.60 (mg/cc) and 8.35 ± 0.57 (mg/cc), respectively. The errors of total strain energy were 1.06% and 0.91%, respectively. Conclusions. The proposed phantomless HU-to-BMD conversion demonstrates the potential of precisely estimating BMD values from CT images without the reference phantom and being utilized as a viable tool for FEA-based quantitative assessment using routine CT images.

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Prediction of risk of fracture in the tibia due to altered bone mineral density distribution resulting from disuse: A finite element study

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1177/0954411914522438 ◽

2014 ◽

Vol 228 (2) ◽

pp. 165-174 ◽

Cited By ~ 8

Author(s):

Magnus K. Gislason ◽

Sylvie Coupaud ◽

Keisuke Sasagawa ◽

Yuji Tanabe ◽

Mariel Purcell ◽

...

Keyword(s):

Bone Mineral Density ◽

Finite Element ◽

Density Distribution ◽

Bone Mineral ◽

Mineral Density ◽

Risk Of Fracture ◽

Finite Element Study ◽

Bone Mineral Density Distribution ◽

Element Study

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The effect of denosumab on pedicle screw fixation: a prospective 2-year longitudinal study using finite element analysis

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02360-2 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Soji Tani ◽

Koji Ishikawa ◽

Yoshifumi Kudo ◽

Koki Tsuchiya ◽

Akira Matsuoka ◽

...

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Elderly Patients ◽

Pedicle Screw ◽

Screw Fixation ◽

Pedicle Screw Fixation ◽

Pullout Strength ◽

Mineral Density ◽

Element Analysis ◽

Denosumab Treatment

Abstract Background Pedicle screw loosening is a major complication following spinal fixation associated with osteoporosis in elderly. However, denosumab is a promising treatment in patients with osteoporosis. The effect of denosumab on pedicle screw fixation is unknown. Therefore, we investigated whether denosumab treatment improves pedicle screw fixation in elderly patients with osteoporosis. Methods This was a 2-year prospective open-label study. From February 2015 to January 2016, we included 21 patients with postmenopausal osteoporosis who received initial denosumab treatment. At baseline, 12 months, and 24 months, we measured volumetric bone mineral density (BMD) using quantitative computed tomography (QCT) and performed CT-based finite element analysis (FEA). Finite element models of L4 vertebrae were created to analyze the bone strength and screw fixation. Results BMD increased with denosumab treatment. FEA revealed that both pullout strength of pedicle screws and compression force of the vertebra increased significantly at 12 and 24 months following denosumab treatment. Notably, pullout strength showed a stronger correlation with three-dimensional volumetric BMD around pedicle screw placement assessed by QCT (r = 0.83, at 24 months) than with two-dimensional areal BMD assessed by dual energy X-ray absorptiometry (r = 0.35, at 24 months). Conclusion To our knowledge, this is the first study to reveal that denosumab treatment achieved strong pedicle screw fixation with an increase in BMD around the screw assessed by QCT and FEA; therefore, denosumab could be useful for osteoporosis treatment during spinal surgery in elderly patients with osteoporosis.

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Effects of 3-year GH replacement therapy on bone mineral density in younger and elderly adults with adult-onset GH deficiency

Acta Endocrinologica ◽

10.1530/eje-11-0886 ◽

2012 ◽

Vol 166 (2) ◽

pp. 181-189 ◽

Cited By ~ 11

Author(s):

Mariam Elbornsson ◽

Galina Götherström ◽

Celina Franco ◽

Bengt-Åke Bengtsson ◽

Gudmundur Johannsson ◽

...

Keyword(s):

Bone Mineral Density ◽

Elderly Patients ◽

Bone Mineral ◽

The Elderly ◽

Marginal Effect ◽

Adult Onset ◽

Mineral Density ◽

Gh Replacement ◽

Femur Neck

ObjectiveLittle is known of the effects of long-term GH replacement on bone mineral content (BMC) and bone mineral density (BMD) in elderly GH-deficient (GHD) adults.Design/patients/methodsIn this prospective, single-center, open-label study, the effects of 3-year GH replacement were determined in 45 GHD patients >65 years and in 45 younger control GHD patients with a mean age of 39.5 (s.e.m.1.1) years. All patients had adult-onset disease and both groups were comparable in terms of number of anterior pituitary hormonal deficiencies, gender, body mass index, and waist:hip ratio.ResultsThe mean maintenance dose of GH was 0.24 (0.02) mg/day in the elderly patients and 0.33 (0.02) mg/day in the younger GHD patients (P<0.01). The 3 years of GH replacement induced a marginal effect on total body BMC and BMD, whereas femur neck and lumbar (L2–L4) spine BMC and BMD increased in both the elderly and the younger patients. The treatment response in femur neck BMC was less marked in the elderly patients (P<0.05 vs younger group). However, this difference disappeared after correction for the lower dose of GH in the elderly patients using an analysis of covariance. There were no between-group differences in responsiveness in BMC or BMD at other skeletal locations.ConclusionsThis study shows that GH replacement increases lumbar (L2–L4) spine and femur neck BMD and BMC in younger as well as elderly GHD patients. This supports the notion that long-term GH replacement is also useful in elderly GHD patients.

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