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1.
Bone Joint J ; 101-B(11): 1416-1422, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31674252

RESUMO

AIMS: In this randomized study, we aimed to compare quality of regenerate in monolateral versus circular frame fixation in 30 patients with infected nonunion of tibia. PATIENTS AND METHODS: Both groups were comparable in demographic and injury characteristics. A phantom (aluminium step wedge of increasing thickness) was designed to compare the density of regenerate on radiographs. A CT scan was performed at three and six months postoperatively to assess regenerate density. A total of 30 patients (29 male, one female; mean age 32.54 years (18 to 60)) with an infected nonunion of a tibial fracture presenting to our tertiary institute between June 2011 and April 2016 were included in the study. RESULTS: The regenerate mineralization on radiographs was comparable in both groups at two, four, six, and ten months' follow-up but the rail fixator group had statistically significant higher grades of mineralization when compared with the circular frame group at eight and 12 months' follow-up. The regenerate mineralization was also higher in the rail fixator group than in the circular frame group on CT at three and six months, although this difference was not statistically significant. CONCLUSION: Overall, the regenerate mineralization was higher in the monolateral than the circular frame group. A monolateral fixator may be preferred in patients with infected nonunion of the tibia with bone defects up to 7 cm. Cite this article: Bone Joint J 2019;101-B:1416-1422.


Assuntos
Fraturas não Consolidadas/cirurgia , Osteogênese por Distração/métodos , Fraturas da Tíbia/cirurgia , Infecção dos Ferimentos/cirurgia , Adolescente , Adulto , Densidade Óssea/fisiologia , Desenho de Equipamento , Fixadores Externos , Feminino , Fixação de Fratura/instrumentação , Fixação de Fratura/métodos , Fraturas não Consolidadas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Osteogênese por Distração/instrumentação , Cuidados Pós-Operatórios/métodos , Estudos Prospectivos , Radiografia , Fraturas da Tíbia/diagnóstico por imagem , Infecção dos Ferimentos/diagnóstico por imagem , Adulto Jovem
2.
Comput Methods Biomech Biomed Engin ; 22(16): 1247-1257, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31497997

RESUMO

One of the major causes of implant loosening is due to excessive bone resorption surrounding the implant due to bone remodelling. The objective of the study is to investigate the effects of implant material and implant-bone interface conditions on bone remodelling around tibia bone due to total ankle replacement. Finite element models of intact and implanted ankles were developed using CT scan data sets. Bone remodelling algorithm was used in combination with FE analysis to predict the bone density changes around the ankle joint. Dorsiflexion, neutral, and plantar flexion positions were considered, along with muscle force and ligaments. Implant-bone interfacial conditions were assumed as debonded and bonded to represent non-osseointegration and fully osseointegration at the porous coated surface of the implant. To investigate the effect of implant material, three finite element models having different material combinations of the implant were developed. For model 1, tibial and talar components were made of Co-Cr-Mo, and meniscal bearing was made of UHMWPE. For model 2, tibial and talar components were made of ceramic and meniscal bearing was made of UHMWPE. For model 3, tibial and talar components were made of ceramic and meniscal bearing was made of CFR-PEEK. Changes in implant material showed no significant changes in bone density due to bone remodelling. Therefore, ceramic appears to be a viable alternative to metal and CFR-PEEK can be used in place of UHMWPE. This study also indicates that proper bonding between implant and bone is essential for long-term survival of the prosthetic components.


Assuntos
Artroplastia de Substituição do Tornozelo , Remodelação Óssea/fisiologia , Próteses e Implantes , Tíbia/fisiologia , Algoritmos , Densidade Óssea/fisiologia , Interface Osso-Implante/fisiologia , Cartilagem/fisiologia , Simulação por Computador , Análise de Elementos Finitos , Humanos , Osseointegração/fisiologia
3.
BMC Public Health ; 19(1): 1076, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399027

RESUMO

BACKGROUND: Chronic inflammation contributes to the risk of osteoporosis and fracture. Dietary Inflammatory Index (DII), a novel method appraising the inflammatory potential of diet, has been utilized to examine the association between diet and bone health among postmenopausal women or the elderly. However, its relationship with bone density (BD) in lactating women has not been studied. METHODS: The prospective study was conducted to assess the possible association between DII and maternal BD during lactation. We enrolled 150 lactating women in the cohort. Participants were measured ultrasonic BD as baseline values at 1 month postpartum. After five-month follow up, the participants' BD were measured again. DII scores were calculated from semi-quantitative food frequency questionnaires (FFQ) and divided into tertiles. We compared the differences in the changes of BD at 6 months postpartum without or with adjustment for potential covariates across the tertiles. RESULTS: The women in Q1 of DII scores had less bone mass loss than those in Q2 and Q3 without adjustment for any covariates (p < 0.01); after adjusting demographic characteristics such as BMI (kg/m2) at 6 months postpartum, educational level, metabolic equivalent (MET), daily energy intake (kcal/d), we found that participants in the highest tertile of DII scores had much more bone loss than those in the lowest tertile (p = 0.038). However, in the test for trend, no significant association between DII and the changes of maternal BD at 6 months postpartum was observed. CONCLUSIONS: Chinese lactating women with higher DII scores have more bone mass loss; however significant differences and trends are attenuated and/or disappear depending on covariates and confounders that are taken into account in statistical analysis. The further study should be conducted in larger population to explore whether the significant association between DII and BD exists in Chinese lactating women.


Assuntos
Densidade Óssea/fisiologia , Dieta/efeitos adversos , Inflamação/fisiopatologia , Lactação/fisiologia , Adulto , China , Feminino , Humanos , Estudos Longitudinais , Período Pós-Parto , Estudos Prospectivos
4.
Br J Radiol ; 92(1103): 20190249, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31469323

RESUMO

OBJECTIVE: The frequency of enostosis incidentally found on CT and CT attenuation value to distinguish them from untreated osteoblastic metastases (UOM). METHODS: Enostosis group: 46 polytrauma patients underwent thoracoabdominal CT. Inclusion criteria: age range 14-35 years. Exclusion criteria: cancer, previous fractures. UOM group: 20 patients with radiological diagnosis of UOM. Analyzed data: number, size, location and density of enostoses and metastases. The density was measured with the broadest possible region of interest at the center of the lesion by two radiologists independently. Receiver operatingcharacteristic analysis to determine the sensitivity and specificity, area under the curve 95% confidence intervals and cutoff values of CT density to differentiate metastases from enostoses. RESULTS: Patients were 28 ± 7 years old (72% males). 41 (89%) patients had 124 enostoses (2-15 mm) with an average density of 1007 ± 122 Hounsfiled unit (HU, observer1) and 1052 ± 107 (observer2). The most common sites of occurrence were the proximal femur (34%), the pelvis (22%), the acetabulum (20%), the proximal humerus (11%), the vertebrae (11%) and the rib (2%). 13 patients had 1 bone island, 8 patients had 2, 9 cases had 3 and 11 cases had more than 3 enostoses. Overall, 114 UOM were evaluated, their average density was 728 ± 163 HU (observer1) and 712 ± 178 HU (observer2). The area under the curve value of mean density to distinguish enostoses from UOM was 0,982. Using a cut-off of 881 HU for mean density, sensitivity was 98% and specificity 95%. CONCLUSION: The frequency of enostosis in this study is 89%. The average density identified can help to distinguish enostoses from UOM. ADVANCES IN KNOWLEDGE: We report the exact frequency of enostosis.


Assuntos
Doenças Ósseas/diagnóstico por imagem , Adolescente , Adulto , Densidade Óssea/fisiologia , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/fisiopatologia , Neoplasias Ósseas/secundário , Diagnóstico Diferencial , Feminino , Humanos , Achados Incidentais , Masculino , Estudos Retrospectivos , Adulto Jovem
5.
Transplant Proc ; 51(7): 2324-2329, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31402249

RESUMO

PURPOSE: In this study, we evaluated the relationship between serum homocysteine level and proteinuria, parathyroid hormone, vitamin D, and bone mineral density in kidney transplant recipients (KTR). MATERIALS AND METHODS: A total of 117 stable KTR older than 18 years was followed in our outpatient clinic. Demographic data were recorded. Simultaneously biochemical parameters, including glucose, blood urea nitrogenous, creatinine, calcium, phosphorus, sodium, potassium, albumin, parathormone, vitamin D3, homocysteine, vitamin B12, folate, and 24-hour urine protein, and bone mineral density of the femoral neck and spine by dual-energy x-ray absorptiometry (DEXA) were measured. RESULTS: DEXA measurements were normal, osteoporotic, and osteopenic (12.3%, 36.3%, and 51.3%, respectively). There was a relationship between the serum homocysteine and usage of rapamycin (P = .05), statins (P = .057), and beta blockers (P = .01), DEXA measurements were not related with serum homocysteine levels and immunosuppressive drugs used. Serum homocysteine levels correlated negatively with blood urea nitrogen (P = .002), creatinine (P = .001), vitamin B12 (P < .001), and a positively daily proteinuria (rho = 0.203, P = .031). There was a negative relationship between proteinuria and serum level of vitamin D. CONCLUSIONS: The bone mineral density decreased in more than 87% of our KTR. We did not find any relationship between DEXA measurements and levels of homocysteine, vitamin D, parathormone, and immunosuppressive drugs. It should be noted that some drugs used may affect serum homocysteine levels. Interestingly, there was a relationship between proteinuria and serum levels of homocysteine and vitamin D. Therefore, serum levels of homocysteine and vitamin D should be evaluated for preventing renal damage in KTR.


Assuntos
Densidade Óssea/efeitos dos fármacos , Homocisteína/sangue , Transplante de Rim , Absorciometria de Fóton , Densidade Óssea/fisiologia , Inibidores de Calcineurina/uso terapêutico , Colecalciferol/sangue , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Proteinúria
7.
Poult Sci ; 98(9): 3611-3616, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31321433

RESUMO

Laying hen skeletal health continues to be an industry priority. Bone ash and bone Ca quantification in laying hen long bones provides valuable information on skeletal health. Unfortunately, these measurements can only be accomplished by sacrificing hens, thus making longitudinal measurements on the same hen impossible. Quantitative computed tomography (QCT), used with a calcium hydroxyapatite phantom, has been used to determine bone density of wings and legs as well as live hens throughout the production cycle by scanning with a calcium hydroxyapatite phantom. QCT has also been used to scan live hens throughout the production cycle. The purpose of this study was to determine how QCT calculated bone mineral content (QCT BMC) corresponds to analytical bone Ca and bone ash. Wing and leg quarters from 72-wk-old W-36 hens were QCT scanned along with a QCT Phantom. After scanning, humeri, femurs, and tibias were cleaned, divided into epiphysis (E) and diaphysis (D), fat extracted, ashed, and digested under nitric acid, and Ca was determined by atomic absorption spectroscopy was used to determine E, D, and whole bone Ca. Four bones/type were used for E and D, while 6 bones/type were used for whole bone measurements. A second set of bones were prepared to determine correlation of BMC to bone ash. QCT scans were analyzed with Mimics software (Materialise NV, Leuven, Belgium) to calculate bone volume and density in Hounsfield units. Utilizing the QCT phantom and bone volume, BMC was calculated for E, D, and whole bone. Data were analyzed with regression analysis and Pearson correlation coefficients were determined. Analytical Ca was correlated to QCT BMC for E (R = 0.84, P < 0.01), D (R = 0.99, P < 0.01), and whole bone (R = 0.97, P < 0.01). Whole bone ash was highly correlated to QCT BMC for femur (N = 47, R = 0.97, P < 0.001), tibia (N = 50, R = 0.94, P < 0.001), and keel (N 50, R = 0.94, P < 0.001). Whole bone ash and QCT BMC values of femur and tibia were not different (P = 0.39 and 0.22 respectively). Based on this information, QCT could provide relative quantitative assessment of total bone mineral in live birds proving useful in long-term studies.


Assuntos
Densidade Óssea/fisiologia , Osso e Ossos/química , Cálcio/metabolismo , Galinhas/fisiologia , Minerais/análise , Animais , Feminino , Fêmur/química , Úmero/química , Esterno/química , Tíbia/química , Tomografia Computadorizada por Raios X/veterinária
8.
Yonsei Med J ; 60(8): 742-750, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31347329

RESUMO

PURPOSE: Muscle mass, strength, and composition determine muscle quantity and quality. However, data on muscle properties in relation to bone mass or insulin resistance are limited in Asian populations. This study aimed to investigate the relative importance of muscle measurements in regards to their relationship with lower bone mass and insulin resistance. MATERIALS AND METHODS: In this study, 192 postmenopausal women (age, 72.39±6.07 years) were enrolled. We measured muscle cross-sectional area (CSA) and attenuation at the gluteus maximus and quadriceps muscles through quantitative computed tomography. Muscle strength and physical performance were evaluated with the hand grip test and Short Physical Performance Battery (SPPB). Pearson correlation analysis and linear regression were performed to evaluate the relationship between muscle properties and homeostatic model assessment-insulin resistance (HOMA-IR) or bone mineral density (BMD). RESULTS: Muscle CSA, hand grip strength, and SPPB score held positive correlations with spine and hip BMDs, but not with insulin resistance. In contrast, muscle attenuation of the gluteus maximus or quadriceps was inversely related to HOMA-IR (r=-0.194, p=0.018 and r=-0.292, p<0.001, respectively), but not BMD. Compared with the control group, muscle CSA was significantly decreased in patients with osteoporosis; however, decreased muscle attenuation, indicating high fat infiltration, was found only in patients with diabetes. CONCLUSION: Muscle mass, strength, and physical performance were associated with low bone mass, and accumulation of intramuscular fat, a histological hallmark of persistently damaged muscles, may play a major role in the development of insulin resistance in Korean postmenopausal women.


Assuntos
Osso e Ossos/anatomia & histologia , Resistência à Insulina , Força Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Pós-Menopausa/fisiologia , Idoso , Índice de Massa Corporal , Densidade Óssea/fisiologia , Estudos Transversais , Diabetes Mellitus/fisiopatologia , Feminino , Força da Mão/fisiologia , Humanos , Tamanho do Órgão , Osteoporose/fisiopatologia , República da Coreia
9.
J Zoo Wildl Med ; 50(2): 375-382, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31260203

RESUMO

Musculoskeletal problems are one of the top five causes of disease in elephants. However, recent blood chemistry analysis is the only routine protocol for bone mineral status evaluation, with no assessment method currently available for the direct measurement of elephant bone mineral density (BMD). This work applied the the dual-energy X-ray technique (DXA) technique for bone density assessment. The elephant's tail was chosen for the analysis to avoid the radiation harm. Twelve live Asian elephants (Elephas maximus) comprising eight males and four females with ages in the range of 4-77 yr were investigated. The BMD was calculated based on radiographic images acquired using the DXA technique carried out at 40 kVp 2 mAs and 50 kVp 2 mAs. Blood serum analysis of total calcium (Ca), phosphorus (Phos) and alkaline phosphatase (ALP) content was conducted in parallel with the physical examination to correlate age and BMD. Analyses produced an overall mean BMD value in the range of 0.54-1.39 g/cm2, with that of the males higher than that of the females. The BMD was found to be negatively correlated with age, Ca, and Phos, but not with ALP. In summary, the BMD analysis of an elephant's tail might be used with blood serum Ca and Phos to predict the overall bone mineral status of the animal.


Assuntos
Absorciometria de Fóton/veterinária , Densidade Óssea/fisiologia , Elefantes/anatomia & histologia , Cauda/anatomia & histologia , Animais , Elefantes/fisiologia , Feminino , Masculino , Cauda/diagnóstico por imagem
10.
J Zoo Wildl Med ; 50(2): 447-452, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31260212

RESUMO

Giant South American turtles (Podocnemis expansa) are at a risk of extinction because of the rapid decline in their population over the last few decades. Metabolic bone disease (MBD) is common in captive testudines, but is often not diagnosed until a later stage. The authors present the cases of four captive giant South American turtles with carapace deformity secondary to MBD that underwent computed tomography (CT) scans of the carapace bones and vertebral column. Findings indicative of changes in geometry were found in both. The cancellous bone pattern was characterized by varying degrees of increased trabecular spacing and cortical thinning of the pleural bones. Bone densitometry analysis of the pleural and neural bones and at the level of the body of the third, fourth, and fifth dorsal vertebrae showed mean density values much lower than those found in two adult specimens of the same species that were considered healthy. In conclusion, CT contributed important information on the degree of demineralization and possible structural changes due to MBD and should be considered a relevant tool for diagnosis of this condition.


Assuntos
Densidade Óssea/fisiologia , Doenças Ósseas Metabólicas/veterinária , Tomografia Computadorizada por Raios X/veterinária , Tartarugas , Animais , Doenças Ósseas Metabólicas/diagnóstico por imagem , Doenças Ósseas Metabólicas/patologia , Feminino , Masculino
11.
J Sports Sci ; 37(19): 2279-2285, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31266396

RESUMO

Cyclists may be at greater risk of developing asymmetrical force and motion patterns than other ground-based athletes. However, functional asymmetries during cycling tend to be highly variable, making them difficult to assess. Dual-energy x-ray absorptiometry (DXA) measurements of areal bone mineral density (aBMD) and lean mass (LM) in the lower limbs may be a more sensitive and consistent method to identify asymmetries in cyclists. The goal of this study was to determine if competitive cyclists have greater levels of asymmetries in the lower body compared to non-cyclists using DXA. A secondary aim was to determine if aBMD and LM asymmetries change over the road cycling season. 17 competitive cyclists and 21 non-cyclist, healthy controls underwent DXA scans. Lower-body asymmetries were greater in cyclists compared to non-cyclists in aBMD and LM for all lower limb segments. However, these asymmetries did not tend to consistently favour a particular side, except for the pelvis having more LM on the dominant side. The were no longitudinal changes in aBMD or LM in the cyclists. Asymmetry analysis via DXA provides evidence that although functional asymmetries during cycling are variable, cyclists have increased lower body LM and aBMD asymmetries compared to non-cyclists.


Assuntos
Ciclismo/fisiologia , Índice de Massa Corporal , Densidade Óssea/fisiologia , Extremidade Inferior/fisiologia , Absorciometria de Fóton , Ciclismo/lesões , Composição Corporal/fisiologia , Comportamento Competitivo/fisiologia , Estudos Transversais , Transtornos Traumáticos Cumulativos/fisiopatologia , Feminino , Humanos , Extremidade Inferior/diagnóstico por imagem , Masculino , Adulto Jovem
12.
Medicine (Baltimore) ; 98(27): e16096, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31277108

RESUMO

Osteoporosis (OP) is a disease characterized by decreased bone mineral density (BMD) and an increased risk of osteoporotic fractures. Nutritional factors (including glucose and fats lipids), have been implicated in OP.We hypothesized that the levels of blood glucose and lipids could be biomarkers for predicting the risk of OP. To test this hypothesis, we evaluated the potential relationship between BMD and levels of blood glucose and lipids via a community-based study in China.This was a community-based cross-section analysis, and a total of 8584 cases were investigated. The BMD of the left calcaneus was measured using an ultrasonic bone densitometer. The levels of blood glucose (fasting blood glucose [FBG], 2-h blood glucose [2hBG], and glycosylated hemoglobin [HbAlc]), and lipids (triglyceride [TG], total cholesterol [TC], low-density lipoprotein cholesterol [LDL-C], and high-density lipoprotein cholesterol [HDL-C]) were measured and analyzed.In our study population, the levels of FBG, 2hBG, HbAlc, TC, LDL-C and HDL-C were higher in the OP group than in the low bone density and the normal bone density groups, while the levels of HbAlc, TC, and LDL-C in the low bone density group were higher than those in the normal bone density group. In males, the level of blood LDL-C in the low bone density group was higher than that in the normal bone density group. In postmenopausal subjects, the levels of FBG, 2hBG and HbA1C were higher than those in the normal bone density groups, and the level of HbA1C in the low bone density group was higher than that in the normal bone density group. Pearson linear trend analysis demonstrated that BMD was positively associated with TC and LDL-C in males and negatively associated with FBG, 2hBG and HbA1C in postmenopausal females. Moreover, logistic analysis showed that BMD was correlated with TC in premenopausal females and HbA1C in postmenopausal females.OP is generally associated with abnormal levels of blood glucose and/or lipids; nevertheless, the relationship between OP and abnormal levels of blood glucose and/or lipids is complicate and different subpopulations may have different susceptibilities. Therefore, further detailed studies are warranted.


Assuntos
Glicemia/análise , Densidade Óssea/fisiologia , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Osteoporose/sangue , Absorciometria de Fóton , Adulto , Idoso , Biomarcadores/sangue , Calcâneo/diagnóstico por imagem , Estudos Transversais , Feminino , Teste de Tolerância a Glucose , Hemoglobina A Glicada/análise , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Fatores de Risco , Inquéritos e Questionários
13.
Vet Surg ; 48(6): 947-955, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31236987

RESUMO

OBJECTIVE: To compare the geometrical properties and bone mineral density (BMD) of the proximal radius between Saint Bernard and other giant breed dogs. STUDY DESIGN: Observational, cross-sectional, descriptive study. ANIMALS: Thirteen client-owned Saint Bernard dogs and 13 other client-owned giant breed dogs. METHODS: Computed tomography (CT) studies of Saint Bernard and other giant breed dogs were reviewed. Multiplanar reconstruction of the CT images was used to determine cross-sectional variables at the proximal half of the radius, including mean cortical thickness (mCT) and moment of inertia (MOI). Cortical BMD was estimated from Hounsfield unit measurements at each cross-section and averaged per bone. One-way analysis of variance was used to detect differences between groups. RESULTS: Proximal radii of Saint Bernard dogs had a lower cortical/medullary ratio (1.75 vs 2.2, P < .001), mCT (1.96 vs 2.64 mm, P < .001), and MOI in all planes (mediolateral [ML]: 2086.09 vs 2757.69 mm4 , P < .001; craniocaudal [CrCd]: 3736.36 vs 4370.28 mm4 , P = .025; and polar: 5852.45 vs 7127.97 mm4 , P = .002) compared with bones of other breeds. Cross-sectional BMD did not differ between groups of dogs, but the mean BMD of all cross-sections was lower in Saint Bernard dogs (1214.27 vs 1289.80 mg/mm3 , P = .029). CONCLUSION: The proximal radii of Saint Bernard dogs had thinner cortices and lower CrCd, ML, and polar MOI compared with corresponding bones in giant breed dogs. CLINICAL SIGNIFICANCE: The structural properties of the proximal radius of the Saint Bernard differ from those in other giant breeds and could reduce the ability of this region to sustain biomechanical loads. These properties could predispose Saint Bernard dogs to complications after surgical limb-sparing procedures.


Assuntos
Densidade Óssea/fisiologia , Osso e Ossos/fisiologia , Cães/fisiologia , Rádio (Anatomia)/fisiologia , Animais , Densidade Óssea/genética , Estudos Transversais , Cães/genética , Feminino , Humanos , Tomografia Computadorizada por Raios X/veterinária
14.
Eur J Radiol ; 116: 212-218, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31153568

RESUMO

OBJECTIVES: To investigate the use of texture analysis for the detection of osteoporosis on noncontrast head CTs, and to explore optimal sampling regions within the craniofacial bones. METHODS: In this IRB-approved, retrospective study, the clivus, bilateral sphenoid triangles and mandibular condyles were manually segmented on each noncontrast head CT, and 41 textures features were extracted from 29 patients with normal bone density (NBD); and 29 patients with osteoporosis. Basic descriptive statistics including a false discovery rate correction were performed to evaluate for differences in texture features between the cohorts. RESULS: Sixteen texture features demonstrated significant differences (P < 0.01) between NBD and osteoporosis in the clivus including 4 histogram features, 2 gray-level co-occurrence matrix features, 8 gray-level run-length features and 2 Law's features. Nineteen texture features including 9 histogram features, 1 GLCM features, 2 GLRL features, 5 Law's features and 2 GLGM features demonstrated statistically significant differences in both sides of the sphenoid triangles. A total 24 texture features demonstrated statistically significant differences between normal BMD and osteoporosis in the left sphenoid and a total of 31 texture features in the left condyle. Furthermore, a total of 22 texture features including 6 histogram features, 3 GLCM features, 9 GLRL features, 2 Law's features and 2 GLGM features demonstrated statistically significant differences in both sides of the mandibular condyles. CONCLUSION: The results of this investigation suggest that specific texture analysis features derived from regions of interest placed within multiple sites within the skull base and maxillofacial bones can distinguish between patients with normal bone mineral density compared to those with osteoporosis. This study demonstrates the potential utility of a texture analysis for identification of osteoporosis on head CT, which may help identify patients who have not undergone screening with traditional DXA.


Assuntos
Densidade Óssea/fisiologia , Osteoporose/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Ossos Faciais/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
15.
Pediatr Surg Int ; 35(8): 911-914, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203385

RESUMO

PURPOSE: The cadmium (Cd) chick model has been described as a reliable model of omphalocele. Skeletal anomalies, including lumber lordosis, can be seen in the Cd chick model, as well as in the human omphalocele. Bone deformations, such as lordosis, are associated with high bone mineral density (BMD). Recently, three-dimensional microcomputed tomography (3DMCT) has been used to investigate skeletal development in small animal embryos. We used 3DMCT to test the hypothesis that the BMD is increased in the Cd-induced omphalocele chick model. METHODS: After a 60-h incubation, chicks were exposed to either chick saline or Cd in ovo. Chick embryos were harvested at embryonic day 16.5 (E16.5) and were divided into control (n = 8) and Cd (n = 9). Chicks were then scanned by 3DMCT. The body volume, bone volume, bone/body volume ratio, bone mineral quantity and BMD were analysed statistically (significance was accepted at p < 0.05). RESULTS: Bone mineral density (mg/cm3) was significantly increased in the Cd group compared to control group (235.3 ± 11.7 vs 223.4 ± 4.6, p < 0.05), whereas there was no significant difference in the bone/body volume ratio between the Cd group and the control group (0.7 ± 0.1 vs 0.6 ± 0.0). The body volume (cm3) (0.3 ± 0.2 vs 0.3 ± 0.1), bone volume (cm3) (0.2 ± 0.2 vs 0.2 ± 0.1), and bone mineral quantity (mg) (51.3 ± 41.6 vs 41.5 ± 16.5) were not significantly different between the two groups. CONCLUSIONS: Increased BMD may be associated with lordosis of the vertebral column in the Cd-induced omphalocele chick model, stimulating osteogenesis by activating the canonical Wnt signalling pathway.


Assuntos
Densidade Óssea/fisiologia , Hérnia Umbilical/diagnóstico , Imagem Tridimensional/métodos , Microtomografia por Raio-X/métodos , Animais , Cádmio/toxicidade , Embrião de Galinha , Modelos Animais de Doenças , Hérnia Umbilical/induzido quimicamente , Organogênese
16.
Einstein (Sao Paulo) ; 17(3): eAO4419, 2019 May 30.
Artigo em Inglês, Português | MEDLINE | ID: mdl-31166483

RESUMO

OBJECTIVE: To compare tissue composition, total and regional bone mineral content and bone mineral density, static hand grip and knee joint isokinetic strength between amateur soccer players and Control Group. METHODS: Cross-sectional study. Air displacement plethysmography was used to estimate body volume and, in turn, density. Body composition, bone mineral content and bone mineral density were assessed for the whole body and at standardized regions using dual energy X-ray absorptiometry. Static grip strength was assessed with an adjustable dynamometer, and peak torque derived from isokinetic strength dynamometer (concentric muscular knee actions at 60°/s). Magnitude of the differences between groups was examined using d-Cohen. RESULTS: Compared to healthy active adults, soccer players showed larger values of whole body bone mineral content (+651g; d=1.60; p<0.01). In addition, differences between groups were large for whole body bone mineral density (d=1.20 to 1.90; p<0.01): lumbar spine, i.e. L1-L4 (+19.4%), upper limbs (+8.6%) and lower limbs (+16.8%). Soccer players attained larger mean values in strength test given by static hand grip protocol (+5.6kg, d=0.99; p<0.01). CONCLUSION: Soccer adequately regulates body composition and is associated better bone health parameters (bone mineral content and density at whole-body and at particular sites exposed to mechanical loadings).


Assuntos
Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Articulação do Joelho/fisiologia , Força Muscular/fisiologia , Futebol/fisiologia , Absorciometria de Fóton , Adolescente , Adulto , Atletas , Estudos Transversais , Força da Mão/fisiologia , Humanos , Extremidade Inferior/fisiologia , Masculino , Dinamômetro de Força Muscular , Pletismografia/métodos , Valores de Referência , Estatísticas não Paramétricas , Extremidade Superior/fisiologia , Adulto Jovem
17.
Med Sci Monit ; 25: 3503-3509, 2019 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-31079139

RESUMO

BACKGROUND The aim of this retrospective study was to compare the measurements of bone mineral density (BMD) combined with volumetric dental tomography measurements taken from three main regions selected on the lower mandible, the right mandibular, medial mandibular, and left mandibular regions, in patients with ectodermal dysplasia and age-matched and gender-matched controls. Measurement of BMD in Hounsfield units (HUs) were evaluated using three-dimensional (3D) cone beam computed tomography (CBCT) imaging. MATERIAL AND METHODS Mandibular bone tomography images were evaluated from 9 women and 5 men diagnosed with ectodermal dysplasia and a control group of 9 women and 5 men. The HU values obtained according to age and gender of the total 28 study participants were measured. Statistical analysis of the data used Student's t-test. RESULTS BMD in the ectodermal dysplasia group was significantly lower compared with the BMD in the control group. Comparison of the left and right mandibular angulus regions showed that the BMD of patients with ectodermal dysplasia was significantly lower when compared with the control group in both regions, but no significant difference was found between the two groups in the BMD of the central mandibular region. CBCT was found to be an effective method for the measurement of BMD. CONCLUSIONS In patients with ectodermal dysplasia, reduced BMD should be taken into consideration when planning surgical interventions involving bone tissue and when planning implant surgery. The results of this study may be of value in dentistry and other fields of medicine.


Assuntos
Densidade Óssea/fisiologia , Tomografia Computadorizada de Feixe Cônico/métodos , Displasia Ectodérmica/fisiopatologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Mandíbula/anatomia & histologia , Mandíbula/fisiologia , Estudos Retrospectivos , Turquia , Adulto Jovem
18.
Sao Paulo Med J ; 137(1): 75-81, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31116275

RESUMO

BACKGROUND: Sports participation plays an important role in bone gain during childhood and adolescence. The aim here was to identify sex-related determinants of bone mineral density (BMD) differences between male and female adolescents, with emphasis on the role of sports participation. DESIGN AND SETTING: Longitudinal study conducted in a public university in Presidente Prudente, Brazil. METHODS: The sample comprised 48 adolescents aged 11-17 years, of both sexes, who were matched according to sex, age and sports participation. BMD was the main outcome, while muscle mass, sports participation, calendar age and biological maturation were treated as covariates. Participants were followed up after nine months. RESULTS: At baseline, BMD values were similar between the sexes. However, adjustment for covariates showed that BMD was higher among girls at all sites, with a contribution from lean soft tissue (LST) in the model (partial eta-squared, ES-r = 0.619 in upper limbs; 0.643 in lower limbs; 0.699 in spine; and 0.599 in whole body). Sports participation only explained the upper-limb variance (ES-r = 0.99). At the follow-up, the results resembled the baseline except in the lower limbs (P = 0.109), in which BMD was similar between the groups. BMD gain over time was similar between girls and boys in all segments, and baseline LST affected upper-limb and whole-body BMD accrual (ES-r = 0.396 and 0.107, respectively). CONCLUSION: Whole-body and specific-site BMD differed between baseline and follow-up. However,BMD accrual was similar between the sexes, given that muscle mass constituted the most relevant determinant of the difference between them.


Assuntos
Densidade Óssea/fisiologia , Músculo Esquelético/fisiologia , Esportes/fisiologia , Absorciometria de Fóton , Adolescente , Desenvolvimento do Adolescente/fisiologia , Índice de Massa Corporal , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Valores de Referência , Fatores Sexuais , Fatores de Tempo
19.
Am J Orthod Dentofacial Orthop ; 155(5): 681-692, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31053284

RESUMO

PURPOSE: The purpose of this study was to determine how micro-osteoperforations (MOPs) affect tooth movements, bone turnover, bone density, and bone volume. METHODS: A split-mouth experimental design with 7 beagle dogs was used to evaluate bone surrounding maxillary second premolars that had been retracted for 7 weeks. One month after the maxillary third premolars were extracted, 8 MOPs (1.5 mm wide and 7 mm deep) were created without flaps with the use of the Propel device (6 were placed 3 mm distal to the second premolar and 2 were placed in the premolar furcation) on one randomly chosen side. The maxillary second premolars were retracted bilaterally with the use of 200 g nickel-titanium closed coil springs. Tooth movements were measured intraorally and radiographically. Microscopic computed tomography was used to evaluate the material density and volume fraction of bone distal to the premolars. Hematoxylin and eosin-stained and fluorescent sections were used to examine the bone remodeling. RESULTS: Neither the intraoral (P = 0.866) nor radiographic (P = 0.528) measures showed statistically significant side differences in tooth movements. There also were no statistically significant differences in the density (P = 0.237) or volume fraction (P = 0.398) of bone through which the premolars were being moved. Fluorescent and histologic evaluations showed no apparent differences in osteoblasts, osteoclasts, or mineralization of bone near the teeth being moved. Bone healing was evident in and near the MOP sites, which had nearly but not completely healed after 7 weeks. Regions of acellular bone were evident extending ∼0.8 mm from the MOP sites. CONCLUSIONS: MOPs placed 3 mm away from teeth do not increase tooth movements and have limited and transitory effect on bone.


Assuntos
Prótese Dentária , Técnicas de Movimentação Dentária/instrumentação , Animais , Dente Pré-Molar/cirurgia , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Planejamento de Prótese Dentária , Cães , Maxila/patologia , Microtomografia por Raio-X
20.
Aging Clin Exp Res ; 31(6): 889-895, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31054116

RESUMO

INTRODUCTION: The impact of the two adipokines, visfatin and retinol-binding protein 4 (RBP-4) on bone mineral density (BMD) has been analysed in various studies with conflicting results. Visfatin is highly expressed in visceral fat with stimulatory effect on osteoblast proliferation and inhibition on osteoclast formation, while RBP-4 acts as a transporter protein for retinol, associated with changes in insulin sensitivity, independent of obesity, with no consensus on its effect on bone metabolism. We evaluated the relationship between serum concentrations of visfatin, RBP-4, markers of insulin resistance and current BMD in treated postmenopausal osteoporosis (PO). METHODS: Demographics, previous treatment, metabolic status, anthropometry, serum Alkaline phosphatise (ALP), visfatin, RBP-4, the HOMA IR (homeostatic model assessment of insulin resistance) index and BMD were evaluated in 61 subjects with PO. Statistical analysis used SPSS v. 25.0, with a level of significance α = 0.05. Regression models were constructed to evaluate the relationship between adipokines and BMD, adjusting for covariates. RESULTS: In multilinear regression analysis, the strongest predictor for current BMD was a previous BMD, followed by ALP and age. RBP4 and HOMA IR were significant predictors, while visfatin had no significant effect. A significant correlation between body mass index (BMI) and BMD at the femoral neck was observed. ALP was negatively correlated with BMD and visfatin positively with RBP4. CONCLUSIONS: Data indicate a positive relationship between BMD and RBP-4, an inverse relationship between markers of insulin resistance, bone turn-over and current BMD. No significant effect of visfatin on BMD was observed.


Assuntos
Densidade Óssea/fisiologia , Citocinas/sangue , Resistência à Insulina/fisiologia , Nicotinamida Fosforribosiltransferase/sangue , Osteoporose Pós-Menopausa/sangue , Proteínas Plasmáticas de Ligação ao Retinol/análise , Idoso , Biomarcadores/sangue , Índice de Massa Corporal , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Obesidade/sangue
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