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Qasim M, López Picazo M, Ruiz Wills C, Noailly J, Di Gregorio S, Del Río Barquero LM, Malouf Sierra J, Humbert L. 3D-DXA Based Finite Element Modelling for Femur Strength Prediction: Evaluation Against QCT. J Clin Densitom 2024; 27:101471. [PMID: 38306806 DOI: 10.1016/j.jocd.2024.101471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 01/10/2024] [Accepted: 01/18/2024] [Indexed: 02/04/2024]
Abstract
Osteoporosis is characterised by the loss of bone density resulting in an increased risk of fragility fractures. The clinical gold standard for diagnosing osteoporosis is based on the areal bone mineral density (aBMD) used as a surrogate for bone strength, in combination with clinical risk factors. Finite element (FE) analyses based on quantitative computed tomography (QCT) have been shown to estimate bone strength better than aBMD. However, their application in the osteoporosis clinics is limited due to exposure of patients to increased X-rays radiation dose. Statistical modelling methods (3D-DXA) enabling the estimation of 3D femur shape and volumetric bone density from dual energy X-ray absorptiometry (DXA) scan have been shown to improve osteoporosis management. The current study used 3D-DXA based FE analyses to estimate femur strength from the routine clinical DXA scans and compared its results against 151 QCT based FE analyses, in a clinical cohort of 157 subjects. The linear regression between the femur strength predicted by QCT-FE and 3D-DXA-FE models correlated highly (coefficient of determination R2 = 0.86) with a root mean square error (RMSE) of 397 N. In conclusion, the current study presented a 3D-DXA-FE modelling tool providing accurate femur strength estimates noninvasively, compared to QCT-FE models.
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Amani A, Bellver M, Del Rio L, Torrella JR, Lizarraga A, Humbert L, Drobnic F. Femur 3D-DXA Assessment in Female Football Players, Swimmers, and Sedentary Controls. Int J Sports Med 2023. [PMID: 35995142 DOI: 10.1055/a-1928-9824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Cortical and trabecular volumetric bone mineral density (vBMD), cortical thickness and surface BMD (sBMD, density-to-thickness ratio) were analyzed in the proximal femur of elite female football players and artistic swimmers using three-dimensional dual-energy X-ray absorptiometry (3D-DXA) software and compared to sedentary controls. Football players had significantly higher (p<0.05) vBMD (mg/cm3) in the trabecular (263±44) and cortical femur (886±69) than artistic swimmers (224±43 and 844±89) and sedentary controls (215±51 and 841±85). Football players had also higher (p<0.05) cortical thickness (2.12±0.19 mm) and sBMD (188±22 mg/cm2) compared to artistic swimmers (1.85±0.15 and 156±21) and sedentary controls (1.87±0.16 and 158±23). Artistic swimmers did not show significant differences in any parameter analyzed for 3D-DXA when compared to sedentary controls. The 3D-DXA modeling revealed statistical differences in cortical thickness and vBMD between female athletes engaged in weight-bearing (football) and non-weight bearing (swimming) sports and did not show differences between the non-weight bearing sport and the sedentary controls. 3D-DXA modeling could provide insight into bone remodeling in the sports field, allowing evaluation of femoral trabecular and cortical strength from standard DXA scans.
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Affiliation(s)
- Amineh Amani
- Cellular Biology, Physiology and Immunology, Universitat de Barcelona, Facultat de Biologia, Barcelona, Spain
- Centre Mèdic, CETIR, Barcelona, Spain
| | - Montse Bellver
- Sports Medicine, Centre Alt Rendiment Sant Cugat del Vallès, Barcelona, Spain
| | | | - Joan Ramon Torrella
- Cellular Biology, Physiology and Immunology, Universitat de Barcelona, Facultat de Biologia, Barcelona, Spain
| | | | | | - Franchek Drobnic
- Sports Medicine, Centre Alt Rendiment Sant Cugat del Vallès, Barcelona, Spain
- Medical Department, Shanghai Shenhau FC, Shanghai, China
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Ng CA, McMillan LB, Humbert L, Ebeling PR, Scott D. Feasibility, safety and effectiveness of a pilot 16-week home-based, impact exercise intervention in postmenopausal women with low bone mineral density. Osteoporos Int 2021; 32:893-905. [PMID: 33159533 DOI: 10.1007/s00198-020-05723-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 10/29/2020] [Indexed: 12/01/2022]
Abstract
UNLABELLED The feasibility and efficacy of home-based, impact exercise are unclear. This pilot impact exercise intervention was feasible and safe, and improved bone health and physical function in postmenopausal women with low bone density. Appropriately designed randomised controlled trials are now required to determine whether such interventions can reduce fracture risk. INTRODUCTION The feasibility and efficacy of impact exercise in postmenopausal women with low bone mineral density (BMD) are unclear. We aimed to determine adherence, safety and changes in BMD, bone microarchitecture and physical function following a pilot home-based, impact exercise intervention in postmenopausal women with low BMD. METHODS Fifty community-dwelling postmenopausal women with BMD T-scores < - 1.0 participated in 16 weeks of home-based impact exercise progressively increasing to 50 multi-directional unilateral hops on each leg daily. Bone density and structure were assessed by lumbar spine and hip dual-energy X-ray absorptiometry (DXA), 3D modelling (3D-SHAPER) of hip DXA scans and distal tibial high-resolution peripheral quantitative computed tomography scans. Physical performance was assessed by repeated chair stand time and stair climb time. RESULTS Forty-four women (mean ± SD age 64.5 ± 7.5 years) completed the intervention, with adherence of 85.3 ± 17.3%. Reasons for withdrawal were related soreness (n = 2), unrelated injury (n = 1) and loss of interest (n = 3). Femoral neck areal BMD increased by 1.13 ± 3.76% (p = 0.048). Trabecular volumetric BMD (vBMD) increased at the total hip (2.27 ± 7.03%; p = 0.038) and femoral neck increased (3.20 ± 5.39%; p < 0.001). Distal tibia total vBMD increased by 0.32 ± 0.88% (p = 0.032) and cortical cross-sectional area increased by 0.55 ± 1.54% (p = 0.034). Chair stand and stair climb time improved by 2.34 ± 1.88 s (p < 0.001) and 0.27 ± 0.49 s (p < 0.001), respectively. CONCLUSION A 16-week home-based, impact exercise was feasible and may be effective in improving femoral neck areal BMD, total hip and distal tibial vBMD and physical function in postmenopausal women. Appropriately designed randomised controlled trials are now required to determine whether such interventions can reduce fracture risk in older populations.
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Affiliation(s)
- C-A Ng
- Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia.
| | - L B McMillan
- Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
| | - L Humbert
- Musculoskeletal Unit, Galgo Medical, Barcelona, Spain
| | - P R Ebeling
- Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
| | - D Scott
- Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Burwood, Victoria, Australia
- Department of Medicine at Western Health, The University of Melbourne, Sunshine, Victoria, Australia
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A pilot study comparing daily teriparatide with monthly cycles of teriparatide and raloxifene. Arch Osteoporos 2021; 16:70. [PMID: 33856570 DOI: 10.1007/s11657-021-00933-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 03/09/2021] [Indexed: 02/03/2023]
Abstract
UNLABELLED This 6-month pilot study in osteoporotic postmenopausal women evaluated cyclic TPD/RLX compared to daily subcutaneous TPD with the concept of optimizing bone formation. Compared to daily subcutaneous TPD, cyclic therapy showed comparable increase in spine BMD and favorable effects on total proximal femur BMD and cortical thickness. PURPOSE There is no cure for osteoporosis; better medications or different approaches with current agents are needed. We hypothesized that monthly cycles of teriparatide (TPD) followed by raloxifene (RLX) might promote ongoing bone formation. Additionally, as TPD might initially adversely affect hip BMD, such effects may be mitigated by a cyclic approach. Therefore, this 6-month pilot study evaluated the effect of cyclic TPD/RLX compared to daily subcutaneous TPD on bone markers, BMD, trabecular bone score (TBS), and hip parameters assessed by 3D modeling. METHODS Postmenopausal osteoporotic women (n=26) were randomized to open-label TPD 20 daily or alternating monthly cycles of TPD followed by monthly RLX 60 mg daily. BMD was measured at the lumbar spine (LS), femur, and radius by DXA. To further assess LS BMD, QCT and opportunistic CT (L1 Hounsfield units [HU]) were performed. LS TBS and hip cortical and trabecular parameters were assessed using DXA. Baseline group comparisons were performed by unpaired T-test with change over time evaluated by repeated measures ANOVA. RESULTS Participant mean age, BMI, and lowest T-score were 67.0 years, 26.0 kg/m2, and -2.7; no between-group differences in serum chemistries, 25(OH)D, or BMD were observed. LS-BMD increased (p<0.001) with TPD or TPD/RLX as measured by DXA (4.8%/5.2%), QCT (13%/9.4%), or HU (15.6%/10.2%) with no between-group difference. TPD/RLX produced beneficial between-group differences in total proximal femur BMD (1.5%, p<0.05) and cortical thickness (1.6%, p<0.05). CONCLUSION Compared with daily TPD, cyclic TPD/RLX comparably increased spine BMD and might have favorable effects on proximal femur BMD and cortical thickness.
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Brance ML, Pons-Estel BA, Quagliato NJ, Jorfen M, Berbotto G, Cortese N, Raggio JC, Palatnik M, Chavero I, Soldano J, Dieguez C, Sánchez A, Del Rio L, Di Gregorio S, Brun LR. Trabecular and cortical bone involvement in rheumatoid arthritis by DXA and DXA-based 3D modelling. Osteoporos Int 2021; 32:705-714. [PMID: 32974730 DOI: 10.1007/s00198-020-05641-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 09/15/2020] [Indexed: 10/23/2022]
Abstract
UNLABELLED Rheumatoid arthritis (RA) patients had a higher risk of developing low bone mineral density (BMD) or osteoporosis. RA patients on classic disease-modifying antirheumatic drug (c-DMARD) therapy showed significantly lower BMD than controls, while no significant differences in most parameters were found between RA patients receiving biological disease-modifying antirheumatic drugs (b-DMARDs) and controls. The 3D analysis allowed us to find changes in the trabecular and cortical compartments. INTRODUCTION To evaluate cortical and trabecular bone involvement of the hip in RA patients by dual-energy X-ray absorptiometry (DXA) and 3D analysis. The secondary end-point was to evaluate bone involvement in patients treated with classic (c-DMARD) or biological (b-DMARD) disease-modifying antirheumatic drug therapies and the effect of the duration of the disease and corticosteroid therapy on 3D parameters. METHODS A cross-sectional study of 105 RA patients and 100 subjects as a control group (CG) matched by age, sex, and BMI was carried out. BMD was measured by DXA of the bilateral femoral neck (FN) and total hip (TH). The 3D analyses including trabecular and cortical BMD were performed on hip scans with the 3D-Shaper software. RESULTS FN and TH BMD and trabecular and cortical vBMD were significantly lower in RA patients. The c-DMARD (n = 75) group showed significantly lower trabecular and cortical vBMD than the CG. Despite the lower values, the b-DMARD group (n = 30) showed no significant differences in most parameters compared with the CG. The trabecular and cortical 3D parameters were significantly lower in the group with an RA disease duration of 1 to 5 years than in the CG, and the trabecular vBMD was significantly lower in the group with a duration of corticosteroid therapy of 1 to 5 years than in the CG, while no significant differences were found by standard DXA in the same period. CONCLUSIONS RA patients had a higher risk of developing low BMD or osteoporosis than controls. RA patients receiving c-DMARD therapy showed significantly lower BMD than controls, while no significant differences in most parameters were found between RA patients receiving b-DMARDs and controls. 3D-DXA allowed us to find changes in trabecular and cortical bone compartments in RA patients.
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Affiliation(s)
- M L Brance
- Reumatología y Enfermedades Óseas, Rosario, Argentina
- Bone Biology Laboratory, School of Medicine, Rosario National University, Rosario, Argentina
- National Council of Scientific and Technical Research (CONICET), Buenos Aires, Argentina
| | - B A Pons-Estel
- Centro Regional de Enfermedades Autoinmunes y Reumáticas (GO-CREAR), Rosario, Argentina
| | | | - M Jorfen
- Reumatología y Enfermedades Óseas, Rosario, Argentina
| | - G Berbotto
- Reumatología y Enfermedades Óseas, Rosario, Argentina
| | - N Cortese
- School of Medicine, Rosario National University, Rosario, Argentina
| | - J C Raggio
- Reumatología y Enfermedades Óseas, Rosario, Argentina
| | - M Palatnik
- Centro de Reumatología, Rosario, Argentina
| | - I Chavero
- Reumatología y Enfermedades Óseas, Rosario, Argentina
| | - J Soldano
- School of Medicine, Rosario National University, Rosario, Argentina
| | - C Dieguez
- Reumatología y Enfermedades Óseas, Rosario, Argentina
| | - A Sánchez
- Centro de Endocrinología, Rosario, Argentina
| | | | | | - L R Brun
- Bone Biology Laboratory, School of Medicine, Rosario National University, Rosario, Argentina.
- National Council of Scientific and Technical Research (CONICET), Buenos Aires, Argentina.
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Jazinizadeh F, Quenneville CE. 3D Analysis of the Proximal Femur Compared to 2D Analysis for Hip Fracture Risk Prediction in a Clinical Population. Ann Biomed Eng 2020; 49:1222-1232. [PMID: 33123827 DOI: 10.1007/s10439-020-02670-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 10/20/2020] [Indexed: 01/22/2023]
Abstract
Due to the adverse impacts of hip fractures on patients' lives, it is crucial to enhance the identification of people at high risk through accessible clinical techniques. Reconstructing the 3D geometry and BMD distribution of the proximal femur could be beneficial in enhancing hip fracture risk predictions; however, it is associated with a high computational burden. It is also not clear whether it provides a better performance than 2D model analysis. Therefore, the purpose of this study was to compare the 2D and 3D model reconstruction's ability to predict hip fracture risk in a clinical population of patients. The DXA scans and CT scans of 16 cadaveric femurs were used to create training sets for the 2D and 3D model reconstruction based on statistical shape and appearance modeling. Subsequently, these methods were used to predict the risk of sustaining a hip fracture in a clinical population of 150 subjects (50 fractured, and 100 non-fractured) that were monitored for five years in the Canadian Multicentre Osteoporosis Study. 3D model reconstruction was able to improve the identification of patients who sustained a hip fracture more accurately than the standard clinical practice (by 40%). Also, the predictions from the 2D statistical model didn't differ significantly from the 3D ones (p > 0.76). These results indicated that to enhance hip fracture risk prediction in clinical practice implementing 2D statistical modeling has comparable performance with lower associated computational load.
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Affiliation(s)
- Fatemeh Jazinizadeh
- Department of Mechanical Engineering, McMaster University, ABB-C308, 1280 Main St. West, Hamilton, ON, L8S 4L8, Canada
| | - Cheryl E Quenneville
- Department of Mechanical Engineering, McMaster University, ABB-C308, 1280 Main St. West, Hamilton, ON, L8S 4L8, Canada.
- School of Biomedical Engineering, McMaster University, Hamilton, ON, Canada.
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García Martín A, de la Higuera López-Frías M, Cortés Berdonces M, Jodar Gimeno E, Ávila Rubio V, Alhambra MR, Muñoz Torres M. New technologies in the evaluation of bone fragility and its application in Endocrinology. ACTA ACUST UNITED AC 2020; 67:602-610. [PMID: 32439320 DOI: 10.1016/j.endinu.2020.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 01/26/2020] [Accepted: 01/28/2020] [Indexed: 10/24/2022]
Abstract
Bone mineral density using dual-energy X-ray absorptiometry is the gold standard for the assessment of bone and an important predictor of fracture risk. However, most fragility fractures occur in people without densitometric osteoporosis, especially in endocrinological diseases. Fracture risk estimation tools such as FRAX have improved diagnostic sensitivity but do not include additional skeletal features. Bone microarchitecture research represents an improvement in the treatment of these patients. In this document members of the Mineral and Bone Metabolism Working Group of the Spanish Society of Endocrinology and Nutrition review new advances in dual-energy X-ray absorptiometry and other complex techniques for the study of bone microarchitecture as well as the available data on type 2 diabetes and parathyroid pathology.
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Affiliation(s)
- Antonia García Martín
- Unidad de Gestión Clínica (UGC) de Endocrinología y Nutrición, Hospital Universitario San Cecilio, CIBERFES, Instituto de Investigación Biosanitaria de Granada (Ibs.GRANADA), Granada, España.
| | | | - María Cortés Berdonces
- Servicio de Endocrinología y Nutrición, Complejo Hospitalario Ruber Juan Bravo, Madrid, España
| | - Esteban Jodar Gimeno
- Departamento de Endocrinología y Nutrición Clínica, Hospital Universitario Quirón Salud Madrid y Hospital Ruber Juan Bravo, Universidad Europea de Madrid, Madrid, España
| | - Verónica Ávila Rubio
- Unidad de Gestión Clínica (UGC) de Endocrinología y Nutrición, Hospital Universitario San Cecilio, CIBERFES, Instituto de Investigación Biosanitaria de Granada (Ibs.GRANADA), Granada, España
| | - María Rosa Alhambra
- UGC de Endocrinología y Nutrición, Hospital Universitario Reina Sofía, Córdoba, España
| | - Manuel Muñoz Torres
- Unidad de Gestión Clínica (UGC) de Endocrinología y Nutrición, Hospital Universitario San Cecilio, CIBERFES, Instituto de Investigación Biosanitaria de Granada (Ibs.GRANADA), Granada, España; Departamento de Medicina, Universidad de Granada, Granada, España
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Ziaeipoor H, Taylor M, Martelli S. Population-Based Bone Strain During Physical Activity: A Novel Method Demonstrated for the Human Femur. Ann Biomed Eng 2020; 48:1694-1701. [PMID: 32103370 DOI: 10.1007/s10439-020-02483-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 02/19/2020] [Indexed: 11/30/2022]
Abstract
Statistical methods are increasingly used in biomechanics for studying bone geometry, bone density distribution and function in the population. However, relating population-based bone variation to strain during activity is computationally challenging. Here, we describe a new method for calculating strain in a population, using the Superposition Principle Method Squared (SPM2), and we demonstrate the method for calculating strain in human femurs. Computed-tomography images and motion capture while walking in 21 healthy adult women were obtained earlier. Variation of femur geometry and bone distribution were modelled using active shape and appearance modelling (ASAM). Femoral strain was modelled as the weighted sum of strain generated by each force in the model plus a strain variation assumed a quadratic function of the ASAM scores. The quadratic coefficients were fitted to 35 instances drawn from the ASAM model by varying each eigenmode by ± 2 SD. The equivalent strain in matched finite-element and SPM2 calculations was obtained for 40 frames of walking for three independent cases and 50 ASAM instances. Finite-element and SPM2 solutions for walking were obtained in 44 and 3 min respectively. The SPM2 model accurately predicted strain for the three independent instances (R-squared 0.83-0.94) and the 50 ASAM instances (R-squared 0.95-1.00). The method developed enables fast and accurate calculation of population-based femoral strain.
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Affiliation(s)
- Hamed Ziaeipoor
- Medical Device Research Institute, College of Science and Engineering, Flinders University, South Rd, Tonsley, SA, 5042, Australia
| | - Mark Taylor
- Medical Device Research Institute, College of Science and Engineering, Flinders University, South Rd, Tonsley, SA, 5042, Australia
| | - Saulo Martelli
- Medical Device Research Institute, College of Science and Engineering, Flinders University, South Rd, Tonsley, SA, 5042, Australia.
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García Hoyos M, Humbert L, Salmón Z, Riancho JA, Valero C. Analysis of volumetric BMD in people with Down syndrome using DXA-based 3D modeling. Arch Osteoporos 2019; 14:98. [PMID: 31494745 DOI: 10.1007/s11657-019-0645-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 08/16/2019] [Indexed: 02/03/2023]
Abstract
UNLABELLED We analyzed volumetric bone mineral density, by 3D analysis, in 76 people with Down syndrome and 76 controls. People with Down syndrome, particularly men, have a lower hip volumetric bone mineral density than the general population. Besides, volumetric bone mineral density declines more rapidly in Down syndrome. INTRODUCTION People with Down syndrome (DS) have a lower areal bone mineral density (aBMD) estimated by dual-energy X-ray absorptiometry (DXA). However, they have smaller-sized bones, which could influence the measurements. Therefore, our objective was to determine volumetric BMD in these patients. MATERIALS AND METHODS We included 76 outpatients with DS and 76 control healthy volunteers matched for age and sex distribution. Clinical data were obtained with a standardized interview and physical exam, including age, sex, height, weight, and body mass index (BMI). aBMD was measured by dual-energy X-ray at the femoral neck (FN) and total hip (TH). The 3D-SHAPER® software (version 2.8, Galgo Medical, Barcelona, Spain) was used to derive 3D analysis from participants' hip DXA scans. RESULTS DS femurs had a similar 3D geometry, compared with the femurs of controls. However, 3D analysis showed that participants with DS had smaller cortical thickness (1.84 mm ± 0.17 vs. 2.02 ± 0.20 mm; p < 0.0001), cortical vBMD (777 ± 49 mg/cm3 vs. 809 ± 43 mg/cm3; p < 0.0001), and cortical sBMD (143 ± 19 mg/cm2 vs. 164 ± 22 mg/cm2; p < 0.0001). After adjustment for age and BMI, all 3D measurements remained lower in DS than in controls. These differences were more marked in men than in women. vBMD decreased with age in controls and DS, but the decline was greater in DS for all 3D parameters. CONCLUSION People with DS, particularly men, have a lower hip vBMD than the general population. Besides, vBMD declines more rapidly in DS.
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Affiliation(s)
- Marta García Hoyos
- Department of Internal Medicine, University Hospital Marqués de Valdecilla, University of Cantabria, IDIVAL, Santander, Spain
| | | | - Zaida Salmón
- Department of Internal Medicine, University Hospital Marqués de Valdecilla, University of Cantabria, IDIVAL, Santander, Spain
| | - José A Riancho
- Department of Internal Medicine, University Hospital Marqués de Valdecilla, University of Cantabria, IDIVAL, Santander, Spain
| | - Carmen Valero
- Department of Internal Medicine, University Hospital Marqués de Valdecilla, University of Cantabria, IDIVAL, Santander, Spain.
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