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ABSTRACT: OBJECTIVES: This study investigated the short term changes in hip structural parameters in high level adolescent soccers and swimmers. METHODS: Twenty-six girl swimmers (15.9±2 years) and 32 girl soccer players (16.2±0.7 years) were investigated before and after 8months of training. Fifteen non-active age-matched adolescents were enrolled at baseline to serve as a reference group. The geometric contributions to bone strength in the proximal femur were quantified using the hip structural analysis technique. RESULTS: Eight months of training had increased the bone density in soccer players but not in swimmers. At the total hip, swimmers conserved their baseline low Z-score values while soccers remained above the normal. At the femoral shaft, the cross sectional area had increased for the two groups with a higher magnitude in soccers (3.17% vs 2.31%; P<0.05). The sub-periosteal width had increased in soccer players (P<0.01) but not in swimmers. The Z-score showed an improvement of cross sectional moment of inertia and section modulus at femoral shaft section for soccers (P<0.001), without any change in swimmers. Remarkably, swimmers had improved the Z-score of buckling ratio (P<0.005), while soccers did not. DISCUSSION/CONCLUSION: A season of training for sport characterized by impact had induced significant bone geometry improvement in late adolescent females despite expectations that this period of growth represents a plateau in bone maturation. This study adds to the existing literature describing intensive swimming practice as lacking an osteogenic effect when assessed by dual energy X-ray absorptiometry.
Joint, bone, spine: revue du rhumatisme 03/2012; · 2.25 Impact Factor
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ABSTRACT: Curve and surface thinning are widely-used skeletonization techniques for modeling objects in three dimensions. In the case of trabecular bone analysis, however, neither curve nor surface thinning is really efficient since the internal geometry of the object is usually composed of both rod and plate shapes. The purpose of this paper is to propose an original method called hybrid skeleton which better matches the geometry of the data compared to curve and surface skeletons. In the hybrid skeleton algorithm, 1D curves represent rod-shaped zones whereas 2D surfaces represent plate-shaped elements.
The proposed hybrid skeleton algorithm is based on a combination of three methods. (1) A new variant of the method proposed by Bonnassie et al. for the classification of voxels as belonging to plate-like or rod-like structures, where the medial axis (MA) algorithm is replaced by a fast and connected skeletonization algorithm. In addition, the reversibility of the MA algorithm is replaced by an isotropic region-growth method to spread the rod and plate labels back to the original object. (2) A well chosen surface thinning method applied on the plate voxels set. (3) A well chosen curve skeleton thinning method applied on the rod voxels set. The efficiency and the robustness of the proposed algorithm were evaluated using synthesis test vectors. A clinical study was led on micro-CT (computed tomography) images of two different populations of osteoarthritic and osteoporotic trabecular bone samples. The morphological and topological characteristics of the two populations were evaluated using the proposed hybrid skeleton as well as the classification algorithm.
When evaluated on test vectors and compared to Bonnassie's algorithm, the proposed classification algorithm gives a slightly better rate of classification. The hybrid skeleton preserves the shape information of the processed objects. Interesting morphological and topological features as well as volumetric ones were extracted from the skeleton and from the classified volumes, respectively. The extracted features enable the two populations of osteoarthritic and osteoporotic trabecular bone samples to be distinguished.
Compared to curve-based or surface-based skeletons, the hybrid skeleton better matches the geometry of the data. Each rod is represented by a one-voxel-thick arc and each plate is represented by a one-voxel-thick surface. The hybrid skeleton as well as the proposed classification algorithm introduce relevant parameters linked to the presence of plates in the trabecular bone data, showing that rods and plates contain independent information about trabeculae. The hybrid skeleton offers a new opportunity for precise studies of porous media such as trabecular bone.
Medical Physics 01/2012; 39(1):168-78. · 2.83 Impact Factor
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ABSTRACT: Rheumatoid arthritis is characterized by an early inflammatory related periarticular osteopenia. A new high resolution direct digital X-ray device has been recently developed to provide bone texture analysis which is designed to assess changes in trabecular bone architecture. For the first time, we have evaluated trabecular bone texture impairment in rheumatoid arthritis patients compared to healthy controls.
In this cross-sectional study, the reproducibility was assessed by three separate digital X-rays of the right hand, with repositioning in 14 late rheumatoid arthritis patients and 14 healthy subjects. Then, trabecular bone texture of the MCP2 and MCP3 from patients enrolled in a prospective cohort of 78 rheumatoid arthritis patients was compared with that of 50 healthy subjects, using three texture parameters: Hmean, co-occurrence and run-length.
The coefficients of variation of the high resolution direct digital X-ray measurements ranged from 0.5 to 1.8%. Only the Hmean parameter was significantly decreased in rheumatoid arthritis patients compared to healthy subjects at MCP2 (0.637±0.040 vs. 0.654±0.032, P<0.05) and at MCP3 (0.646±0.044 vs. 0.665±0.037, P<0.05). This reduction was significantly correlated to disease activity.
This study demonstrated both the good reproducibility of the high resolution digital X-ray measurements and the trabecular bone texture impairment at MCP joints in rheumatoid arthritis patients. In addition to provide a high resolution hand radiograph, this technique may represent an interesting tool to easily quantify periarticular osteopenia with a low radiation dose.
Joint, bone, spine: revue du rhumatisme 11/2011; 79(4):379-83. · 2.25 Impact Factor
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ABSTRACT: Bone microarchitecture can be studied noninvasively using high-resolution peripheral quantitative computed tomography (HR-pQCT). However, this technique is not widely available, so more simple techniques may be useful. BMA is a new 2D high-resolution digital X-ray device, allowing for bone texture analysis with a fractal parameter (H(mean)). The aims of this study were (1) to evaluate the reproducibility of BMA at two novel sites (radius and tibia) in addition to the conventional site (calcaneus), (2) to compare the results obtained with BMA at all of those sites, and (3) to study the relationship between H(mean) and trabecular microarchitecture measured with an in vivo 3D device (HR-pQCT) at the distal tibia and radius. BMA measurements were performed at three sites (calcaneus, distal tibia, and radius) in 14 healthy volunteers to measure the short-term reproducibility and in a group of 77 patients with chronic kidney disease to compare BMA results to HR-pQCT results. The coefficient of variation of H(mean) was 1.2, 2.1, and 4.7% at the calcaneus, radius, and tibia, respectively. We found significant associations between trabecular volumetric bone mineral density and microarchitectural variables measured by HR-pQCT and H(mean) at the three sites (e.g., Pearson correlation between radial trabecular number and radial H(mean) r = 0.472, P < 0.001). This study demonstrated a significant but moderate relationship between 2D bone texture and 3D trabecular microarchitecture. BMA is a new reproducible technique with few technical constraints. Thus, it may represent an interesting tool for evaluating bone structure, in association with biological parameters and DXA.
Calcified Tissue International 11/2010; 87(5):385-91. · 2.38 Impact Factor
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ABSTRACT: To evaluate dietary calcium intake in postmenopausal women over 45 years of age and compare intake according to osteoporosis diagnosis and fracture history.
A cross-sectional epidemiological survey of osteoporosis in postmenopausal women over 45 years in the general population was conducted using a stratified random sampling method and face-to-face interviews. Information was collected on osteoporosis diagnosis, fracture history and risk factors. Information on dietary calcium intake was collected using a validated questionnaire.
Two thousand six hundred and thirty-one women (mean age: 67.9+/-10.0 years) were included. Two hundred and fifty-four (9.7%) had received a diagnosis of osteoporosis by bone densitometry, of whom 154 (45.3%) reported at least one previous fracture. Total mean daily dietary calcium intake was 754 mg/day, of which dairy products (milk, cheese and others) were the principal source. Overall, 37.2% of the sample consumed<600 mg/day and 20.1% >1000 mg/d. The proportion of women consuming <600 mg/day increased with age (p=0.0028). No difference in mean daily calcium intake was observed between women with or without a diagnosis of osteoporosis or with or without fractures.
Mean dietary calcium intake in this population is well below that recommended in current national guidelines (> or =1500 mg/day), notably in those most at risk for fractures, such as women with a diagnosis of osteoporosis or those in older age groups. Intake does not appear to be influenced by osteoporosis diagnosis or fracture experience.
Joint, bone, spine: revue du rhumatisme 02/2010; 77(2):154-8. · 2.25 Impact Factor
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Advanced Concepts for Intelligent Vision Systems - 12th International Conference, ACIVS 2010, Sydney, Australia, December 13-16, 2010, Proceedings, Part I; 01/2010
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ABSTRACT: To determine the prevalence of diagnosed osteoporosis, the extent of treatment use and the incidence of fracture in a representative sample of the French general population.
A cross-sectional epidemiological survey of osteoporosis in 2613 women over 45 years in the general population was conducted using a stratified random sampling method and face-to-face interviews. Information was collected on the diagnosis of osteoporosis, fracture history, treatments, clinical and sociodemographic variables. Variables potentially associated with fracture were evaluated using stepwise multivariate logistic regression analysis.
The overall prevalence of diagnosed osteoporosis was 9.7% [8.6%; 10.9%] and prevalence increased linearly with age. Overall, 155 women (61.0%) received osteoporosis treatment and treatment rates also increased with age. The most frequently prescribed treatments were bisphosphonates, in 50.3% of treated women. The treatment duration was over 2 years for 72.9% of treated women. Overall, 115 (45.3%) reported at least one previous fracture. Vertebral fractures were reported by 101 women (39.8%) and limb fractures by 41 women (16.1%). Multivariate logistic regression analysis identified fracture before the age of 40, menopause before the age of 40, use of sleeping pills, consultation with an eye specialist and history of cardiovascular disease as variables independently associated with fracture.
Osteoporosis in France appears to be under-diagnosed and under-treated. Awareness and management of risk factors for osteoporosis and fracture could thus be improved.
Joint, bone, spine: revue du rhumatisme 04/2009; 76(4):394-400. · 2.25 Impact Factor
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ABSTRACT: Measurement of bone density by densitometry is an appropriate public health strategy for prevention of osteoporotic fractures in at-risk individuals, and physicians are encouraged to screen for these risk factors in post-menopausal women.
To determine the frequency of risk factors for osteoporosis in a representative sample of the French general population in order to estimate the number of women eligible for bone densitometry.
A cross-sectional epidemiological survey of osteoporosis in 2081 post-menopausal women over 45 years in the general population was conducted using a stratified random sampling method and face-to-face interviews. Information was collected on personal or family history of vertebral fracture or limb fracture, endocrine disorders, corticosteroid use, and early menopause. Body mass index was determined during the interview by measuring height and weight.
A total of 1041 women interviewed (51.8%) reported at least one risk factor for osteoporosis and would thus be eligible for densitometry. The most frequently reported risk factor was vertebral fracture or collapse (20.8%), followed by endocrine disorders (10.5%) and long-term corticosteroid treatment (10.5%). The prevalence of vertebral and limb fracture increased with age. Multiple risk factors were reported by 381 women and the proportion of women presenting multiple risk factors increased with age.
Extrapolated to the general population, over five million women in France would be eligible for densitometry. Since only a small proportion of these currently receive a diagnosis of osteoporosis, a considerable number of women could thus potentially benefit from more widespread use of densitometry.
Joint, bone, spine: revue du rhumatisme 08/2008; 75(6):702-7. · 2.25 Impact Factor
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Proceedings of the 2008 IEEE International Symposium on Biomedical Imaging: From Nano to Macro, Paris, France, May 14-17, 2008; 01/2008
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ABSTRACT: Bone fragility can be defined as an increased risk of fractures. Advanced age and bone diseases such as osteoporosis increase the fracture risk. Understanding the effects of osteoporosis and its treatments requires a description of the mechanical behavior of bone tissue. To this end, an entire bone can be studied, or the cortical and trabecular components can be investigated separately. We review the biomechanical tests available for measuring the ability of bone to withstand torsional, compressive, tensile, and bending forces.
Joint, bone, spine: revue du rhumatisme 06/2007; 74(3):233-9. · 2.25 Impact Factor
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ABSTRACT: We investigated the effects of calcium supplementation and physical practice on the bone ultrasound properties and trabecular microarchitecture in children. 160 children aged 8-11 were randomly allocated to active or nonactive groups and to receive either a calcium-phosphate or a placebo powder for 6 months. Skeletal status was assessed using an ultrasound technique, which measures the speed of sound (Ad-SoS, m/s) at the phalanx. Bone microarchitecture was characterized by fractal analysis measured on calcaneus radiographs and the result expressed as the Hmean parameter, that has been shown to a good reliability of the bone texture quality. After 6 months, the calcium group had significantly gained Ad-SoS compared to the placebo group (P = 0.01) and Hmean increase was greater in the active than the nonactive group (P < 0.05). Exercise and calcium supplementation had a differential effect on the bone tissue, calcium being rather linked to a systemic effect whereas exercise has acted better onto the skeletal stressed site.
International journal of sport nutrition and exercise metabolism 12/2006; 16(6):580-96. · 2.01 Impact Factor
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Eric Lespessailles
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ABSTRACT: There is no linear relation between changes in bone mineral density (BMD) and reduction in fracture risk with antiresorptive agents. Interpretation of BMD changes at the individual level requires calculating the smallest significant change at each measurement center. BMD measurement is essential before administration of antiresorptive or anabolic agents for prevention or treatment of postmenopausal osteoporosis. Biochemical markers of bone turnover can be monitored after 6 months of treatment. Their interpretation requires careful assessment of their intraindividual variability.
La Presse Médicale 11/2006; 35(10 Pt 2):1565-70. · 0.67 Impact Factor
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ABSTRACT: At present, fracture risk prediction in the individual patient relies chiefly on bone mineral density (BMD) measurements. However, many lines of evidence indicate that the decreased bone strength characteristic of osteoporosis is dependent not only on BMD, but also on other factors, most notably bone microarchitecture. Here, we review available tools for characterizing trabecular microarchitecture (in terms of morphology, topology, and texture) and for obtaining 2D and 3D images (using radiography, computed tomography, and magnetic resonance imaging). Bone microarchitecture imaging is a noninvasive method that may improve fracture risk prediction in the individual patient, shed light on the pathophysiology of osteoporosis, and help to monitor the effects of treatments. Among the various methods available to date, magnetic resonance imaging has the advantage of involving no radiation exposure, although its limited availability restricts its usefulness for studying vast populations. Regardless of the methods selected to assess bone microarchitecture, there is a need for validated standardized parameters capable of improving fracture risk prediction in longitudinal studies.
Joint Bone Spine 06/2006; 73(3):254-61. · 2.27 Impact Factor
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Joint Bone Spine 07/2003; 70(3):234-5. · 2.27 Impact Factor
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Joint Bone Spine 11/2002; 69(5):519-20. · 2.27 Impact Factor
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ABSTRACT: The authors report a case of osteoid osteoma located simultaneously at the right carpitate and at the proximal part of the right third metacarpian. A 31-year-old man presented in 1997 an osteoid osteoma involving the right capitate. One year after the surgical excision of the tumor, a second osteoid osteoma reappears to the same place requiring a 2nd intervention. A 3rd osteoid osteoma was discovered 16 months later at the proximal part of the right third metacarpian. After every excision, the pathological aspect was compatible with a nidus of osteoid osteoma. Osteoid osteoma of capitate are very rare. Multifocal forms are exceptional. If relapses of the tumor are sometimes explained by the incomplete excision of the nidus, the pathogenesis of the true recurrence remains unclear.
Joint Bone Spine 06/2002; 69(3):327-30. · 2.27 Impact Factor
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ABSTRACT: L'analyse de la texture trabéculaire osseuse obtenue par radiographie pourrait permettre de caractériser l'architecture interne de l'os. Celle-ci est constituée de plusieurs réseaux de travées qui se superposent par projection lors de la radiographie. L'image texturée ainsi obtenue possède de fortes variations de contraste et de luminosité. L'analyse par un modèle fractal orienté basé sur le mouvement brownien fractionnaire permet de s'affranchir, en partie, des problèmes de non-stationnarité et d'anisotropie. Le résultat de l'analyse est représenté sur un diagramme polaire donnant la valeur du paramètre H (avec H = 2 - dimension fractale) en fonction de l'angle d'analyse. En ne conservant que quelques valeurs de la transformée de Fourier polaire de ce diagramme on obtient des paramètres représentatifs de la texture et de son orientation. Ces coefficients sont différents suivant les os radiographiés.
14° Colloque sur le traitement du signal et des images, 1993 ; p. 1272-1275.
