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1.
Turk J Med Sci ; 53(1): 29-39, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36945935

RESUMEN

BACKGROUND: We have evaluated the effects of taurine and aqueous garlic extract (AGE) as a dietary supplement on osteoporotic fracture (OPF) healing in the ovariectomized rat femur fracture model. METHODS: In this experimental animal study,twenty-four osteoporosis-remodeled female Wistar albino rats were randomly divided into 3 groups (n: 8) according to their supplemented diet; control, taurine, and AGE groups. Unilateral femur middiaphysis mini-open osteotomy was stabilized with Kirschner wires. Six weeks after osteotomy, the rats were sacrificed before the femurs were harvested and OPF healing was evaluated with biochemical, histologic, microcomputed-tomography, and scintigraphic methods. RESULTS: As an indicator of the antiosteoporotic effect, the calcium levels of the taurine group were significantly lower than the AGE and control groups in biochemical analyzes (p < 0.01). In histological studies, the new bone diameter and new bone volume values of the taurine group were significantly higher than the control group (p = 0.002 and p = 0.032, respectively), while higher trabecular-compact callus was observed in the taurine and AGE groups, respectively, compared to the control group. In morphological analyses, taurine and AGE groups had significantly higher bone volume/tissue volume, trabecular number, bone surface density, and lower trabecular separation than the control group (p < 0.05). The scintigraphic imaging showed a significant increase in osteoblastic activity of the taurine group compared to the control group (p = 0.005). DISCUSSION: Taurine and AGE have positive anabolic effects, respectively, on the healing of OPFs, demonstrated by biochemical, histological, morphological, and scintigraphic methods.


Asunto(s)
Ajo , Fracturas Osteoporóticas , Femenino , Animales , Ratas , Humanos , Fracturas Osteoporóticas/patología , Taurina/farmacología , Taurina/uso terapéutico , Ratas Wistar , Densidad Ósea , Antioxidantes , Dieta , Suplementos Dietéticos , Ovariectomía
2.
Med Sci Monit ; 26: e923713, 2020 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-32535613

RESUMEN

BACKGROUND The incidence of osteoporotic vertebral fractures (OVCFs) has increased significantly in recent years. In order to assess osteoporotic fracture healing process, it is necessary to study the characteristics after this type of vertebral fracture. However, there are few researches on fracture healing process in severe OVCFs. We aim to investigate the histological healing process and the kinetics of bone turnover markers following severe OVCFs. MATERIAL AND METHODS There were 149 patients with severe OVCFs included in this study. Fasting blood samples were obtained to detect bone turnover markers levels. A transpedicular bone biopsy was performed to collect bone biopsy specimens during vertebroplasty surgery. Stratification of healing process was performed: stage I (1-3 days), stage II (4-10 days), stage III (11-20 days), stage IV (21-30 days), stage V (1-3 months), stage VI (3-6 months). RESULTS Quantitative analysis of bone histomorphometry showed that a large amount of necrotic bone tissue was observed in stage VI (12.92±3.66%). Bone turnover markers showed the concentration of ß-isomerized C-terminal telopeptide (ß-CTX) which reflects activity in osteoclast continued to increase in stage VI (0.9±0.33 ng/mL). These results differed from previous reports of other type vertebral fractures. CONCLUSIONS Bone histomorphometric analysis and bone turnover markers showed that severe osteoporotic vertebral compression fractures often associated with delayed union and nonunion during the healing process.


Asunto(s)
Remodelación Ósea , Curación de Fractura , Fracturas por Compresión/metabolismo , Fracturas Osteoporóticas/metabolismo , Fracturas de la Columna Vertebral/metabolismo , Anciano , Anciano de 80 o más Años , Fosfatasa Alcalina/metabolismo , Biopsia , Calcio/metabolismo , Colágeno Tipo I/metabolismo , Femenino , Fracturas por Compresión/patología , Fracturas por Compresión/cirugía , Humanos , Masculino , Necrosis , Osteocalcina/metabolismo , Fracturas Osteoporóticas/patología , Fracturas Osteoporóticas/cirugía , Fragmentos de Péptidos/metabolismo , Péptidos/metabolismo , Fósforo/metabolismo , Procolágeno/metabolismo , Fracturas de la Columna Vertebral/patología , Fracturas de la Columna Vertebral/cirugía , Columna Vertebral/patología , Vertebroplastia
3.
Med Sci Monit ; 25: 3133-3139, 2019 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-31030207

RESUMEN

BACKGROUND Osteoporosis is an increasingly prevalent disease characterized by decreased bone mass and deterioration of the bone microstructure, which contribute to increased fragility and subsequent fragility fractures, especially in elderly individuals. Rhizoma Drynariae (DRE) is among the most frequently used herbal medicines for the treatment of osteoporosis. Transdermal delivery is a proven novel pathway for drug treatment and has several advantages over traditional drug delivery routes. MATERIAL AND METHODS Female Sprague-Dawley osteoporotic fracture model rats were divided into 3 groups: the control group, the DRE (90 mg/kg/day) group and the DRE cataplasm (containing 30 mg DRE, administered at right femur site daily) group. At 3 and 6 weeks after operation, we performed x-ray, histological, and biomechanical analyses, and evaluated bone marrow density of the femur. RESULTS Treatment with DRE increased callus formation and bone union compared with the control group. Moreover, DRE enhanced bone strength at the femoral diaphysis in the osteoporotic fractures in rats by increasing the ultimate load and stiffness compared with the control group. Furthermore, DRE restored the trabecular bone mineral density in the femur compared with the control group. DRE cataplasm application further enhanced the therapeutic effects against osteoporotic fracture in this rat model. CONCLUSIONS DRE cataplasm application might be useful against osteoporotic fracture.


Asunto(s)
Curación de Fractura/efectos de los fármacos , Fracturas Osteoporóticas/tratamiento farmacológico , Polypodiaceae/metabolismo , Animales , Densidad Ósea/efectos de los fármacos , Callo Óseo/patología , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/farmacología , Femenino , Fracturas del Fémur/tratamiento farmacológico , Fémur/patología , Medicina Tradicional China/métodos , Osteoporosis/tratamiento farmacológico , Fracturas Osteoporóticas/patología , Ratas , Ratas Sprague-Dawley , Rizoma/química
4.
Curr Opin Endocrinol Diabetes Obes ; 24(6): 402-410, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28857846

RESUMEN

PURPOSE OF REVIEW: Trabecular bone score (TBS) is a lumbar spine dual-energy absorptiometry texture index which provides information on skeletal quality partially independent of bone mineral density (BMD). A body of work has emerged demonstrating the relationship between TBS and fracture risk, with lower TBS values associated with increased risk for osteoporotic fracture in postmenopausal women and older men. TBS is derived from standard DXA images; however, the information provided by TBS is complementary to that provided by BMD. In this article, we review the current state of TBS and its evolving role in the assessment and management of osteoporosis, with particular emphasis on the literature of the previous year. RECENT FINDINGS: TBS-adjusted The Fracture Risk Assessment tool (FRAX) probabilities enhance fracture risk prediction compared with conventional FRAX predictions. TBS has been found to better categorize fracture risk and assists in FRAX-based treatment decisions, particularly for patients close to an intervention threshold. However, change in lumbar spine TBS while undergoing antiresorptive treatment is not a useful indicator of antifracture effect. SUMMARY: Lumbar spine TBS is a recently developed image-based software technique for skeletal assessment, complementary to conventional BMD, which has been shown to be clinically useful as a fracture risk prediction tool.


Asunto(s)
Absorciometría de Fotón , Densidad Ósea , Hueso Esponjoso/diagnóstico por imagen , Técnicas de Diagnóstico Endocrino , Osteoporosis/diagnóstico , Fracturas Osteoporóticas/diagnóstico , Hueso Esponjoso/patología , Humanos , Vértebras Lumbares , Osteoporosis/complicaciones , Osteoporosis/patología , Fracturas Osteoporóticas/patología , Valor Predictivo de las Pruebas , Proyectos de Investigación , Medición de Riesgo
5.
Nano Lett ; 17(10): 6210-6216, 2017 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-28892393

RESUMEN

Osteocytes are contained within spaces called lacunae and play a central role in bone remodelling. Administered frequently to prevent osteoporotic fractures, antiresorptive agents such as bisphosphonates suppress osteocyte apoptosis and may be localized within osteocyte lacunae. Bisphosphonates also reduce osteoclast viability and thereby hinder the repair of damaged tissue. Osteocyte lacunae contribute to toughening mechanisms. Following osteocyte apoptosis, the lacunar space undergoes mineralization, termed "micropetrosis". Hypermineralized lacunae are believed to increase bone fragility. Using nanoanalytical electron microscopy with complementary spectroscopic and crystallographic experiments, postapoptotic mineralization of osteocyte lacunae in bisphosphonate-exposed human bone was investigated. We report an unprecedented presence of ∼80 nm to ∼3 µm wide, distinctly faceted, magnesium whitlockite [Ca18Mg2(HPO4)2(PO4)12] crystals and consequently altered local nanomechanical properties. These findings have broad implications on the role of therapeutic agents in driving biomineralization and shed new insights into a possible relationship between bisphosphonate exposure, availability of intracellular magnesium, and pathological calcification inside lacunae.


Asunto(s)
Proceso Alveolar/efectos de los fármacos , Conservadores de la Densidad Ósea/farmacología , Fosfatos de Calcio/química , Difosfonatos/farmacología , Magnesio/química , Osteocitos/efectos de los fármacos , Proceso Alveolar/química , Proceso Alveolar/citología , Proceso Alveolar/patología , Apoptosis/efectos de los fármacos , Conservadores de la Densidad Ósea/uso terapéutico , Cristalización , Difosfonatos/uso terapéutico , Femenino , Humanos , Osteocitos/química , Osteocitos/citología , Osteocitos/patología , Fracturas Osteoporóticas/tratamiento farmacológico , Fracturas Osteoporóticas/patología
6.
Biomed Mater ; 12(3): 035004, 2017 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-28580902

RESUMEN

The development of a new generation of biomaterials with high osteogenic ability for treatment of osteoporotic fractures is being intensively investigated. The objective of this paper was to investigate new bone formation in an ovariectomized rat (OVX rat) calvarial model of critical size bone defects filled with Sr-containing α-calcium sulfate hemihydrate (SrCSH) cement compared to an α-calcium sulfate hemihydrate (α-CSH) cement and empty defect. X-ray diffraction analysis verified the partial substitution of Sr2+ for Ca2+ did not change the phase composition of α-CSH. Scanning electron microscopy showed that Sr-substituted α-CSH significantly increased the surface roughness. The effects of Sr substitution on the biological properties of SrCSH cement were evaluated by adhesion, proliferation, alkaline phosphatase (ALP) activity of osteoblast-like cells MC3T3-E1. The results showed that SrCSHs enhanced MC3T3-E1 cell proliferation, differentiation, and ALP activity. Furthermore, SrCSH cement was used to repair critical-sized OVX rat calvarial defects. The in vivo results revealed that SrCSH had good osteogenic capability and stimulated new blood vessel formation in a critical sized OVX calvarial defect within 12 weeks, suggesting that SrCSH cement has more potential for application in bone tissue regeneration.


Asunto(s)
Sustitutos de Huesos/síntesis química , Sustitutos de Huesos/uso terapéutico , Sulfato de Calcio/química , Osteogénesis , Fracturas Osteoporóticas/terapia , Fracturas Craneales/terapia , Estroncio/química , Células 3T3 , Animales , Femenino , Ensayo de Materiales , Ratones , Fracturas Osteoporóticas/patología , Fracturas Osteoporóticas/fisiopatología , Ovariectomía , Ratas , Ratas Sprague-Dawley , Fracturas Craneales/patología , Fracturas Craneales/fisiopatología , Resultado del Tratamiento
7.
Injury ; 47 Suppl 3: S15-S21, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27692101

RESUMEN

INTRODUCTION: The gradual aging of the population results in increased incidence of osteoporotic bone fractures. In a good quality bone, the fixation with the usual methods is adequate, but not in osteoporotic bone, in which consolidation delays and other complications are common, with failure rates for screws up to 25%. OBJECTIVE: To test fibronectin loaded hydroxyapatite as a complementary treatment for osteoporotic fractures. MATERIAL AND METHODS: This study was performed in a vivo model; 42 female osteoporotic adult rabbits 4-5kg (White New Zealand) were used. Two groups (hydroxyapatite and fibronectin loaded hydroxyapatite) and a control group were tested. 3 time points 24h, 48h and 5days were studied. Defects were created in both femurs, in one of them, a cannulated screw (4mm) and a biocompatible material were placed; in the other femur a screw was inserted without supplemented material forming the control group. Osteoporosis was induced from models already known throughout administration of steroids. Samples were analyzed histologically and through imaging (micro Ct). RESULTS: Basal levels of BMD are observed below to normal when compared to other studies (0.25/0.3 instead of 0.4). Global and dependent of time analysis of samples, show no significant differences for samples analyzed. However, an important trend was noted for variables that define the trabecular bone microarchitecture. Indices that define trabecular microarchitecture in the comparative analysis found to have statistical differences (p<0.01). DISCUSSION: Osteosynthesis in an osteoporotic bone is a challenge for the surgeon, due to a reduced bone mineral density and different bone architecture. The main finding was the verification of the hypothesis that the trabecular bone parameters increases with our augmentation material in weak rabbit bone quality. Also, the histological analyses of samples show an increase of non inflammatory cells in protein samples (OHAp-Fn) from the first 24hours. CONCLUSION: An early response of rabbit osteroporotic bone to a complementary treatment with fibronectin loaded hydroxyapatite has been observed. This response is reflected in greater values for indices that define the trabecular bone microarchitecture, thickness and separation, a greater non-inflammatory cellularity after only 24hours and an increased amount of connective tissue observed at 48hours.


Asunto(s)
Fosfatos de Calcio/uso terapéutico , Fibronectinas/uso terapéutico , Osteoporosis/patología , Fracturas Osteoporóticas/tratamiento farmacológico , Fracturas Osteoporóticas/cirugía , Animales , Cementos para Huesos/farmacología , Densidad Ósea , Tornillos Óseos , Fosfatos de Calcio/farmacología , Modelos Animales de Enfermedad , Durapatita/farmacología , Femenino , Fracturas del Fémur/tratamiento farmacológico , Fracturas del Fémur/patología , Fracturas del Fémur/cirugía , Fibronectinas/farmacología , Osteoporosis/terapia , Fracturas Osteoporóticas/patología , Conejos
8.
Injury ; 47 Suppl 4: S107-S111, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27558243

RESUMEN

INTRODUCTION: Osteoporosis is characterised by poor bone quality arising from alterations to trabecular bone. However, recent studies have also described an important role of alterations to cortical bone in the physiopathology of osteoporosis. Although dual-energy X-ray absorptiometry (DXA) is a valid method to assess bone mineral density (BMD), real bone fragility in the presence of comorbidities cannot be evaluated with this method. The aim of this study was to evaluate if cortical thickness could be a good parameter to detect bone fragility in patients with hip fracture, independent of BMD. METHODS: A retrospective study was conducted on 100 patients with hip fragility fractures. Cortical index was calculated on fractured femur (femoral cortical index [FCI]) and, when possible, on proximal humerus (humeral cortical index [HCI]). All patients underwent densitometric evaluation by DXA. RESULTS: Average value of FCI was 0.43 and of HCI was 0.25. Low values of FCI were found in 21 patients with normal or osteopenic values of BMD, while low values of HCI were found in three patients with non-osteoporotic values of BMD. DISCUSSION AND CONCLUSION: Cortical thinning measured from X-Ray of the femur identifies 21% additional fracture cases over that identified by a T-score <-2.5 (57%). FCI could be a useful tool to evaluate bone fragility and to predict fracture risk even in patients with normal and osteopenic BMD.


Asunto(s)
Hueso Cortical/patología , Fémur/patología , Fracturas de Cadera/patología , Osteoporosis/patología , Fracturas Osteoporóticas/patología , Tomografía Computarizada por Rayos X , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Densidad Ósea , Comorbilidad , Suplementos Dietéticos , Femenino , Indicadores de Salud , Fracturas de Cadera/diagnóstico por imagen , Fracturas de Cadera/epidemiología , Humanos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Osteoporosis/diagnóstico por imagen , Osteoporosis/epidemiología , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/epidemiología , Estudios Retrospectivos , Medición de Riesgo , Vitamina D/uso terapéutico
9.
Injury ; 47 Suppl 1: S21-4, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26768284

RESUMEN

Elderly people, due to neurological conditions and muscular atrophy, present a greater propensity to falls and thus are very susceptible to hip fractures. Other variables, such as osteoporosis, may also be related to the etiopathogenesis of hip fractures, although osteoporosis is in fact a concurrent disease, and merely a coadjutant cause. Nonetheless, osteoporosis can make fracture patterns more severe and interfere with osteosynthesis. Osteoporosis is the radiological image of osteopenia, a pathological concept meaning a smaller quantity of bone per unit of volume. The radiological expression of osteopenia is therefore that of bone tissue with a lower radiological density than normal. In the context of hip fractures, bone mineral density and bone architecture of the femoral neck together with protein expression profiles and cross-links of this anatomical area are of special interest which is reviewed in the current paper. Spatial variations in bone mineral density in the femoral neck were found in the literature with increased porosity from the periosteal to the endosteal region and also from the distal to the proximal part of the femoral neck. Furthermore, increased crystal size, increased cortical porosity, reduced osteocyte lacunar density and an increased Ca/P ratio associated with higher concentrations of Ca and P were described in hip fracture patients compared to control patients. Osteocalcin/collagen type 1 expression ratio and enzymatic cross-link content in high-density bone was found to be significantly lower in hip fractures compared to controls. In conclusion, further research in bone mineral density and associated parameters are of interest to deepen the understanding of osteoporotic hip fractures.


Asunto(s)
Densidad Ósea , Cuello Femoral/metabolismo , Fracturas de Cadera/metabolismo , Osteoporosis/fisiopatología , Fracturas Osteoporóticas/metabolismo , Accidentes por Caídas , Calcio/metabolismo , Colágeno Tipo I/metabolismo , Cuello Femoral/patología , Fracturas de Cadera/patología , Fracturas de Cadera/fisiopatología , Humanos , Osteocalcina/metabolismo , Osteoporosis/complicaciones , Osteoporosis/metabolismo , Fracturas Osteoporóticas/patología , Fracturas Osteoporóticas/fisiopatología , Fósforo/metabolismo , Factores de Riesgo
10.
Proc Inst Mech Eng H ; 228(12): 1281-95, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25515229

RESUMEN

Osteoporosis is a progressive bone disease characterized by deterioration in the quantity and quality of bone, leading to inferior mechanical properties and an increased risk of fracture. Current assessment of osteoporosis is typically based on bone densitometry tools such as Quantitative Computed Tomography (QCT) and Dual Energy X-ray absorptiometry (DEXA). These assessment modalities mainly rely on estimating the bone mineral density (BMD). Hence present densitometry tools describe only the deterioration of the quantity of bone associated with the disease and not the affected morphology or microstructural changes, resulting in potential incomplete assessment, many undetected patients, and unexplained fractures. In this study, an in-silico parametric model of vertebral trabecular bone incorporating both material and microstructural parameters was developed towards the accurate assessment of osteoporosis and the consequent risk of bone fracture. The model confirms that the mechanical properties such as strength and stiffness of vertebral trabecular tissue are highly influenced by material properties as well as morphology characteristics such as connectivity, which reflects the quality of connected inter-trabecular parts. The FE cellular solid model presented here provides a holistic approach that incorporates both material and microstructural elements associated with the degenerative process, and hence has the potential to provide clinical practitioners and researchers with more accurate assessment method for the degenerative changes leading to inferior mechanical properties and increased fracture risk associated with age and/or disease such as Osteoporosis.


Asunto(s)
Densidad Ósea , Modelos Biológicos , Fracturas Osteoporóticas/fisiopatología , Fracturas de la Columna Vertebral/fisiopatología , Columna Vertebral/fisiopatología , Anisotropía , Fuerza Compresiva , Simulación por Computador , Módulo de Elasticidad , Análisis de Elementos Finitos , Humanos , Fracturas Osteoporóticas/patología , Medición de Riesgo/métodos , Fracturas de la Columna Vertebral/patología , Columna Vertebral/patología , Resistencia a la Tracción , Soporte de Peso
11.
Age Ageing ; 42(2): 156-62, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23132148

RESUMEN

BACKGROUND: patients with Parkinson's disease (PD) have a high risk of sustaining osteoporotic fractures as a result of falls and reduced bone mass. OBJECTIVE: to summarise the underlying pathophysiological mechanisms of bone loss in PD by reviewing the available literature. METHODS: a Medline search was performed for articles published between January 1975 and January 2011, using the keywords 'bone mineral density', 'bone loss', 'bone metabolism', 'osteoporosis', 'osteopenia', 'Parkinson's disease' and 'Parkinsonism'. RESULTS: PD patients have a lower bone mineral density (BMD) than age-matched controls. Bone loss in PD is multifactorial, resulting from immobility, decreased muscle strength, and low body weight. Vitamin D deficiency is also important, not only because it reduces BMD, but also because cell function in the substantia nigra depends on vitamin D. Lastly, hyperhomocysteinaemia, an independent risk factor for osteoporosis, is common in PD, due to levodopa use, as well as vitamin B12 and folic acid deficiency. A few studies have demonstrated that treatment with bisphosphonates, vitamin D and calcium can increase BMD and reduce fractures in PD patients. CONCLUSION: bone loss in PD is multifactorial. It is clinically important because of the concomitant risk of fractures. Screening for osteoporosis should be considered more often, and therapeutic interventions should be initiated.


Asunto(s)
Accidentes por Caídas , Huesos/fisiopatología , Osteoporosis/etiología , Fracturas Osteoporóticas/etiología , Enfermedad de Parkinson/complicaciones , Factores de Edad , Anciano , Densidad Ósea , Conservadores de la Densidad Ósea/uso terapéutico , Remodelación Ósea , Huesos/efectos de los fármacos , Huesos/patología , Calcio/uso terapéutico , Suplementos Dietéticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/tratamiento farmacológico , Osteoporosis/patología , Osteoporosis/fisiopatología , Fracturas Osteoporóticas/patología , Fracturas Osteoporóticas/fisiopatología , Fracturas Osteoporóticas/prevención & control , Enfermedad de Parkinson/patología , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/terapia , Medición de Riesgo , Factores de Riesgo , Conducta de Reducción del Riesgo , Factores Sexuales , Resultado del Tratamiento , Vitamina D/uso terapéutico , Deficiencia de Vitamina D/complicaciones
12.
Osteoporos Int ; 23(4): 1297-309, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21695535

RESUMEN

UNLABELLED: The interrelation of calcium and phosphorus was evaluated as a function of bone material quality in femoral heads from male fragility fracture patients via surface analytical imaging as well as scanning microscopy techniques. A link between fragility fractures and increased calcium to phosphorus ratio was observed despite normal mineralization density distribution. INTRODUCTION: Bone fragility in men has been recently recognized as a public health issue, but little attention has been devoted to bone material quality and the possible efficacy in fracture risk prevention. Clinical routine fracture risk estimations do not consider the quality of the mineralized matrix and the critical role played by the different chemical components that are present. This study uses a combination of different imaging and analytical techniques to gain insights into both the spatial distribution and the relationship of phosphorus and calcium in bone. METHODS: X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry imaging techniques were used to investigate the relationship between calcium and phosphorus in un-embedded human femoral head specimens from fragility fracture patients and non-fracture age-matched controls. The inclusion of the bone mineral density distribution via backscattered scanning electron microscopy provides information about the mineralization status between the groups. RESULTS: A link between fragility fracture and increased calcium and decreased phosphorus in the femoral head was observed despite normal mineralization density distribution. Results exhibited significantly increased calcium to phosphorus ratio in the fragility fracture group, whereas the non-fracture control group ratio was in agreement with the literature value of 1.66 M ratio in mature bone. CONCLUSIONS: Our results highlight the potential importance of the relationship between calcium and phosphorus, especially in areas of new bone formation, when estimating fracture risk of the femoral head. The determination of calcium and phosphorus fractions in bone mineral density measurements may hold the key to better fracture risk assessment as well as more targeted therapies.


Asunto(s)
Calcio/análisis , Fracturas del Cuello Femoral/metabolismo , Cabeza Femoral/química , Fracturas Osteoporóticas/metabolismo , Fósforo/análisis , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo de Cadera , Estudios de Casos y Controles , Fracturas del Cuello Femoral/patología , Fracturas del Cuello Femoral/cirugía , Cabeza Femoral/ultraestructura , Humanos , Masculino , Microscopía Electrónica de Rastreo/métodos , Fracturas Osteoporóticas/patología , Fracturas Osteoporóticas/cirugía , Espectroscopía de Fotoelectrones/métodos , Espectrometría de Masa de Ion Secundario/métodos
13.
Exp Gerontol ; 47(2): 136-42, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22138375

RESUMEN

BACKGROUND AND OBJECTIVE: The goal of this study was to investigate the effects of low level laser therapy (LLLT) in osteoporotic rats by means of subjective histopathological analysis, deposition of collagen at the site of fracture, biomechanical properties and immunohistochemistry for COX-2, Cbfa-1 and VEGF. MATERIAL AND METHODS: A total of 30 female Wistar rats (12weeks-old, ±250g) were submitted to ovariectomy (OVX). Eight weeks after the OVX, a tibial bone defect was created in all animals and they were randomly divided into 3 groups (n=10): control bone defect group (CG): bone defects without any treatment; laser 60J/cm(2) group (L60): animals irradiated with LLLT, at 60J/cm(2) and laser 120J/cm(2) group (L120): animals irradiated with LLLT, at 120J/cm(2). RESULTS: In the laser treated groups, at both fluences, a higher amount of newly formed bone was evidenced as well as granulation tissue compared to control. Picrosirius analysis demonstrated that irradiated animals presented a higher deposition of collagen fibers and a better organization of these fibers when compared to other groups, mainly at 120J/cm(2). COX-2, Cbfa-1 or VEGF immunoreactivity was detected in a similar manner either 60J/cm(2) or 120J/cm(2) fluences. However, no differences were shown in the biomechanical analysis. CONCLUSION: Taken together, our results support the notion that LLLT improves bone repair in the tibia of osteoporotic rats as a result of stimulation of the newly formed bone, fibrovascularization and angiogenesis.


Asunto(s)
Regeneración Ósea/efectos de la radiación , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Ciclooxigenasa 2/metabolismo , Terapia por Luz de Baja Intensidad/métodos , Fracturas Osteoporóticas/patología , Fracturas Osteoporóticas/radioterapia , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Biomarcadores/metabolismo , Relación Dosis-Respuesta en la Radiación , Femenino , Miembro Posterior , Inmunohistoquímica , Fracturas Osteoporóticas/metabolismo , Ovariectomía , Dosificación Radioterapéutica , Distribución Aleatoria , Ratas , Ratas Wistar , Tibia/metabolismo , Tibia/patología , Tibia/efectos de la radiación , Resultado del Tratamiento
14.
Clin Orthop Relat Res ; 469(7): 1925-30, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21387105

RESUMEN

BACKGROUND: Osteoporosis, the underlying cause of most hip fractures, is underdiagnosed and undertreated. The 2008 Joint Commission report Improving and Measuring Osteoporosis Management showed only an average of 20% of patients with low-impact fracture are ever tested or treated for osteoporosis. We developed an integrated model utilizing hospitalists and orthopaedic surgeons to improve care of osteoporosis in patients with hip fracture. QUESTIONS/PURPOSES: Does our integrated model combining hospitalists and orthopaedic surgeons improve the frequency of evaluation for osteoporosis, screening for secondary causes, and patients' education on osteoporosis? PATIENTS AND METHODS: Our Hospitalist-Orthopaedic Surgeon Integrated Model of Care was implemented in September 2009. We compared the rate of evaluation and treatment of osteoporosis in 140 patients admitted with fragility hip fracture at our institution before (70 patients) and after (70 patients) implementation of the care plan. RESULTS: Evaluation of patients for osteoporosis was higher in the postimplementation group compared to the preimplementation group (89% versus 24%). Screening of patients for secondary causes of osteoporosis was also improved in the postimplementation group (89% versus 0%), as was the proportion of patients who received education for osteoporosis management (89% versus 0%). CONCLUSION: Our model of integrated care by hospitalists and orthopaedic surgeons resulted in improvement in the evaluation for osteoporosis, screening for secondary causes of osteoporosis, and education on osteoporosis management in patients with hip fracture at our institution. This may have important implications for treatment of these patients. LEVEL OF EVIDENCE: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.


Asunto(s)
Prestación Integrada de Atención de Salud , Fracturas de Cadera/patología , Tamizaje Masivo/métodos , Osteoporosis/diagnóstico , Fracturas Osteoporóticas/patología , Anciano , Anciano de 80 o más Años , Femenino , Fracturas de Cadera/epidemiología , Fracturas de Cadera/etiología , Médicos Hospitalarios , Humanos , Masculino , Persona de Mediana Edad , Modelos Organizacionales , Ortopedia , Osteoporosis/complicaciones , Osteoporosis/epidemiología , Osteoporosis Posmenopáusica , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología
15.
Osteoporos Int ; 22(1): 289-97, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20204596

RESUMEN

UNLABELLED: Young mice over-expressing Runx2 fail to gain bone relative to wild type mice with growth and present spontaneous fractures. It allows, for the first time in rodents, direct assessment of anti-fracture efficacy of strontium ranelate which was able to decrease caudal vertebrae fracture incidence through an improvement of trabecular and cortical architecture. INTRODUCTION: The aim was to investigate whether strontium ranelate was able to decrease fracture incidence in mice over-expressing Runx2, model of severe developmental osteopenia associated with spontaneous vertebral fractures. METHODS: Transgenic mice and their wild type littermates were treated by oral route with strontium ranelate or vehicle for 9 weeks. Caudal fracture incidence was assessed by repeated X-rays, resistance to compressive loading by biochemical tests, and bone microarchitecture by histomorphometry. RESULTS: Transgenic mice receiving strontium ranelate had significantly fewer new fractures occurring during the 9 weeks of the study (-60%, p < 0.05). In lumbar vertebrae, strontium ranelate improves resistance to compressive loading (higher ultimate force to failure, +120%, p < 0.05) and trabecular microarchitecture (higher bone volume and trabecular number, lower trabecular separation, +60%, +50%, -39%, p < 0.05) as well as cortical thickness (+17%, p < 0.05). In tibiae, marrow cavity cross-section area and equivalent diameter were lower (-39%, -21%, p < 0.05). The strontium level in plasma and bone was in the same range as the values measured in treated postmenopausal women. CONCLUSIONS: This model allows, for the first time, direct assessment of anti-fracture efficacy of strontium ranelate treatment in rodents. In these transgenic mice, strontium ranelate was able to decrease caudal vertebral fracture incidence through an improvement of trabecular and cortical architecture.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Fracturas Espontáneas/prevención & control , Compuestos Organometálicos/uso terapéutico , Osteoporosis/tratamiento farmacológico , Fracturas de la Columna Vertebral/prevención & control , Tiofenos/uso terapéutico , Animales , Calcio/sangre , Cauda Equina/lesiones , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos/métodos , Femenino , Fracturas Espontáneas/metabolismo , Fracturas Espontáneas/patología , Vértebras Lumbares/efectos de los fármacos , Vértebras Lumbares/patología , Vértebras Lumbares/fisiopatología , Ratones , Ratones Transgénicos , Osteoporosis/metabolismo , Osteoporosis/patología , Fracturas Osteoporóticas/metabolismo , Fracturas Osteoporóticas/patología , Fracturas Osteoporóticas/prevención & control , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/metabolismo , Fracturas de la Columna Vertebral/patología , Estrés Mecánico , Estroncio/metabolismo , Tibia/efectos de los fármacos , Tibia/patología
16.
Osteoporos Int ; 21(12): 2109-14, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20204601

RESUMEN

SUMMARY: The aim of the present study was to determine the action of AsGA laser irradiation on bone repair in the tibia of osteopenic rats. The animals were randomly divided into eight experimental groups according to the presence of ovarian hormone (sham group) or the absence of the hormone (OVX group), as well as being irradiated or non-irradiated. Low-level 904-nm laser (50 mJ/cm(2)) accelerated the repair process of osteopenic fractures, especially in the initial phase of bone regeneration. INTRODUCTION: The development of new techniques to speed the process of bone repair has provided significant advances in the treatment of fractures. Some attention recently focused on the effects of biostimulation on bone. METHODS: Forty-eight adult rats were randomly divided into eight experimental groups (six animals in each group) according to the presence of ovarian hormone (sham group) or absence of the hormone (ovariectomized (OVX) group) as well as being irradiated or non-irradiated. For the application of low-level laser therapy, the animals were anesthetized with one third of the dose sufficient to immobilize the animal and irradiated with AsGa laser (904 nm, 50 mJ/cm(2) for 2 s, point form and in contact). The control animals received the same type of manipulation as the irradiated animals, but with the laser turned off. Half of the animals were killed 7 days following the confection of the bone defect, and the other half were killed 21 days after the surgery. After complete demineralization, the tibias were cut cross-sectionally in the central region of the bone defect and embedded in paraffin blocks. The blocks were then cut in semi-seriated slices and stained with hematoxylin and eosin. RESULTS: There was new bone formation in the animals in the OVX group with laser treatment killed after 7 days (p < 0.001). The lowest percentage of bone formation was observed in the OVX without laser killed after 7 days (p > 0.05). All animals killed after 21 days exhibited linear closure of the lesion. CONCLUSION: Low-level 904-nm laser (50 mJ/cm(2)) accelerated the repair process of osteopenic fractures, especially in the initial phase of bone regeneration.


Asunto(s)
Terapia por Luz de Baja Intensidad/métodos , Fracturas Osteoporóticas/radioterapia , Animales , Regeneración Ósea/efectos de la radiación , Modelos Animales de Enfermedad , Femenino , Curación de Fractura/efectos de la radiación , Fracturas Osteoporóticas/patología , Ovariectomía , Ratas , Ratas Wistar , Fracturas de la Tibia/patología , Fracturas de la Tibia/radioterapia
17.
Joint Bone Spine ; 77 Suppl 2: S133-8, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21211751

RESUMEN

Official recommendations are available for detecting osteoporosis and initiating osteoporosis medications in postmenopausal women. However, there are no recommendations about the management of patients with incident fractures despite osteoporosis therapy. Second-line osteoporosis treatments have been evaluated only based on laboratory and absorptiometry criteria. Nevertheless, we will try to answer the following questions: (1) What criteria should be used to determine whether a fracture during osteoporosis treatment indicates treatment failure (low-energy fracture, fracture not due to an intercurrent health condition, fracture of the type targeted by the osteoporosis treatment, sufficient treatment duration at occurrence of the fracture, and good adherence to the treatment and to vitamin D supplementation)? (2) In patients with treatment failure or an inadequate clinical response, defined as a fracture despite adherence to osteoporosis therapy for at least 1 year, what are the best treatment strategies?


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Fracturas Osteoporóticas/terapia , Compuestos de Calcio/administración & dosificación , Suplementos Dietéticos , Sustitución de Medicamentos , Femenino , Curación de Fractura/efectos de los fármacos , Fracturas por Estrés/complicaciones , Fracturas por Estrés/patología , Humanos , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/patología , Fracturas Osteoporóticas/etiología , Fracturas Osteoporóticas/patología , Cooperación del Paciente , Insuficiencia del Tratamiento , Deficiencia de Vitamina D/complicaciones , Privación de Tratamiento
18.
Osteoporos Int ; 20(11): 1911-9, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19333675

RESUMEN

UNLABELLED: Treatment rates of osteoporosis after fracture are very low. Women who suffer a fragility fracture have a greater chance of receiving anti-fracture treatment if they had low bone mineral density (BMD), a fracture at the hip, femur or pelvis, administration of calcium and vitamin D supplements and/or an age > or =60 years. INTRODUCTION: This investigation identifies the predictors of osteoporosis treatment 6 to 8 months following fragility fracture in women >50 years of age. METHODS: In this prospective cohort study, women were recruited 0 to 16 weeks following fracture and classified as having experienced fragility or traumatic fractures (phase 1). Six to 8 months following fracture, women completed a questionnaire on demographic features, clinical characteristics and risk factors for osteoporosis (phase 2). Osteoporosis treatment was defined as initiating anti-fracture therapy (bisphosphonate, raloxifene, nasal calcitonin and teriparatide) after fracture in those previously untreated. RESULTS: Of the 1,273 women completing phase 1, 1,001 (79%) sustained a fragility fracture, and of these women, 738 were untreated for osteoporosis at phase 1 and completed the phase 2 questionnaire. Significant predictors of treatment included BMD result, fracture site, administration of calcium and vitamin D supplements at the time of fracture and age > or =60 years. All other risk factors for osteoporosis, such as fracture history after the age of 40 years, family history of osteoporosis and comorbidities did not significantly influence the treatment rate. CONCLUSIONS: Physicians largely based their decision to treat on BMD results and not on the clinical event-fragility fracture.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/tratamiento farmacológico , Fracturas Osteoporóticas/etiología , Anciano , Densidad Ósea , Calcio/uso terapéutico , Toma de Decisiones , Suplementos Dietéticos , Utilización de Medicamentos/estadística & datos numéricos , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/fisiopatología , Fracturas Osteoporóticas/patología , Fracturas Osteoporóticas/prevención & control , Selección de Paciente , Prevención Secundaria , Factores Socioeconómicos , Vitamina D/uso terapéutico
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