Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 18 de 18
Filter
1.
Arch. endocrinol. metab. (Online) ; 66(5): 611-620, Sept.-Oct. 2022. tab
Article in English | LILACS-Express | LILACS | ID: biblio-1420075

ABSTRACT

Abstract Energy metabolism is a point of integration among the various organs and tissues of the human body, not only in terms of consumption of energy substrates but also because it concentrates a wide interconnected network controlled by endocrine factors. Thus, not only do tissues consume substrates, but they also participate in modulating energy metabolism. Soft mesenchymal tissues, in particular, play a key role in this process. The recognition that high energy consumption is involved in bone remodeling has been accompanied by evidence showing that osteoblasts and osteocytes produce factors that influence, for example, insulin sensitivity and appetite. Additionally, there are significant interactions between muscle, adipose, and bone tissues to control mutual tissue trophism. Not by chance, trophic and functional changes in these tissues go hand in hand from the beginning of an individual's development until aging. Likewise, metabolic and nutritional diseases deeply affect the musculoskeletal system and adipose tissue. The present narrative review highlights the importance of the interaction of the mesenchymal tissues for bone development and maintenance and the impact on bone from diseases marked by functional and trophic disorders of adipose and muscle tissues. Arch Endocrinol Metab. 2022;66(5):611-20

2.
Arch. endocrinol. metab. (Online) ; 66(5): 633-641, Sept.-Oct. 2022. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1420077

ABSTRACT

Abstract Globally, one in 11 adults has diabetes mellitus of which 90% have type 2 diabetes. The numbers for osteoporosis are no less staggering: 1 in 3 women has a fracture after menopause, and the same is true for 1 in 5 men after the age of 50 years. Aging is associated with several physiological changes that cause insulin resistance and impaired insulin secretion, which in turn lead to hyperglycemia. The negative balance between bone resorption and formation is a natural process that appears after the fourth decade of life and lasts for the following decades, eroding the bone structure and increasing the risk of fractures. Not incidentally, it has been acknowledged that diabetes mellitus, regardless of whether type 1 or 2, is associated with an increased risk of fracture. The nuances that differentiate bone damage in the two main forms of diabetes are part of the intrinsic heterogeneity of diabetes, which is enhanced when associated with a condition as complex as osteoporosis. This narrative review addresses the main parameters related to the increased risk of fractures in individuals with diabetes, and the mutual factors affecting the treatment of diabetes mellitus and osteoporosis. Arch Endocrinol Metab. 2022;66(5):633-41

3.
Arch. endocrinol. metab. (Online) ; 66(5): 591-603, Sept.-Oct. 2022. tab
Article in English | LILACS-Express | LILACS | ID: biblio-1420087

ABSTRACT

ABSTRACT Several drugs are available for the treatment of osteoporosis in postmenopausal women. Over the last decades, most patients requiring pharmacological intervention were offered antiresorptive drugs as first-line therapy, while anabolic agents were considered a last resource for those with therapeutic failure. However, recent randomized trials in patients with severe osteoporosis have shown that anabolic agents reduce fractures to a greater extent than antiresorptive medications. Additionally, evidence indicates that increases in bone mineral density (BMD) are maximized when patients are treated with anabolic agents first, followed by antiresorptive therapy. This evidence is key, considering that greater increases in BMD during osteoporosis treatment are associated with a more pronounced reduction in fracture risk. Thus, international guidelines have recently proposed an individualized approach to osteoporosis treatment based on fracture risk stratification, in which the stratification risk has been refined to include a category of patients at very high risk of fracture who should be managed with anabolic agents as first-line therapy. In this document, the Brazilian Society of Endocrinology and Metabolism and the Brazilian Association of Bone Assessment and Metabolism propose the definition of very high risk of osteoporotic fracture in postmenopausal women, for whom anabolic agents should be considered as first-line therapy. This document also reviews the factors associated with increased fracture risk, trials comparing anabolic versus antiresorptive agents, efficacy of anabolic agents in patients who are treatment naïve versus those previously treated with antiresorptive agents, and safety of anabolic agents.

4.
Arch. endocrinol. metab. (Online) ; 65(4): 500-504, July-Aug. 2021. graf
Article in English | LILACS | ID: biblio-1339102

ABSTRACT

SUMMARY The occurrence of fractures in young individuals is frequently overlooked by physicians, especially when associated with exercise or trauma. Nevertheless, multiple fractures should always be investigated since underlying conditions can predispose to such events. We describe here the case of a young, healthy woman who sustained multiple fractures in the lower limbs, which were initially considered to be "stress fractures". Further investigation, including a panel of genes associated with osteogenesis imperfecta, revealed that the patient is a heterozygous carrier of a SERPINF1 variant. According to criteria recommended by the American College of Medical Genetics and Genomics and the Association for Molecular Pathology, this variant is classified as likely benign (PM2, PP3, PP4, BP1, and BP4). The patient's mother and brother were also asymptomatic carriers of the variant and had sustained previous minor fractures. The patient had normal biochemical profile and bone density. This condition has been rarely described and is not associated with low bone mineral density or altered bone turnover markers. This case highlights the importance of investigating multiple fractures in young patients who are otherwise healthy since these may be a warning sign of rare genetic conditions associated with fragility fractures.


Subject(s)
Humans , Male , Female , Osteogenesis Imperfecta/genetics , Fractures, Stress/genetics , Fractures, Stress/diagnostic imaging , Bone Density/genetics , Genetic Predisposition to Disease/genetics
5.
Clinics ; 75: e1766, 2020. tab, graf
Article in English | LILACS | ID: biblio-1133370

ABSTRACT

OBJECTIVE: Dual-energy X-ray absorptiometry (DXA)-derived bone mineral density (BMD) often fails to predict fragility fractures. Quantitative textural analysis using magnetic resonance imaging (MRI) may potentially yield useful radiomic features to predict fractures. We aimed to investigate the correlation between BMD and texture attributes (TAs) extracted from MRI scans and the interobserver reproducibility of the analysis. METHODS: Forty-nine volunteers underwent lumbar spine 1.5-T MRI and DXA. Three-dimensional (3-D) gray-level co-occurrence matrices were measured from routine sagittal T2 fast spin-echo images using the IBEX software. Twenty-two TAs were extracted from 3-D segmented L3 vertebrae. The estimated concordance coefficient was calculated using linear regression analysis. A Pearson correlation coefficient analysis was performed to evaluate the correlation between BMD and the TAs. Interobserver reproducibility was assessed with the concordance coefficient described by Lin. RESULTS: The results revealed a fair-to-moderate significant correlation between BMD and 13 TAs (r=−0.20 to 0.39; p<0.05). Eight TAs (autocorrelation, energy, homogeneity 1, homogeneity 1.1, maximum probability, sum average, sum variance, and inverse difference normalized) negatively correlated with BMD (r=−0.20 to −0.38; p<0.05), whereas five TAs (dissimilarity, difference entropy, entropy, sum entropy, and information measure corr 1) positively correlated with BMD (r=0.29-0.39; p<0.05). The interobserver agreement was almost perfect for all significant TAs (95% confidence interval, 0.92-1.00; p<0.05). CONCLUSION: Specific TAs could be reliably extracted from routine MRI and correlated with BMD. Our results encourage future evaluation of the potential usefulness of quantitative texture measurements from MRI scans for predicting fragility fractures.


Subject(s)
Humans , Bone Density , Lumbar Vertebrae/diagnostic imaging , Magnetic Resonance Imaging , Absorptiometry, Photon , Reproducibility of Results
6.
Arch. endocrinol. metab. (Online) ; 62(1): 106-124, Jan.-Feb. 2018. tab
Article in English | LILACS | ID: biblio-887625

ABSTRACT

ABSTRACT Objective To present an update on the diagnosis and treatment of hypoparathyroidism based on the most recent scientific evidence. Materials and methods The Department of Bone and Mineral Metabolism of the Sociedade Brasileira de Endocrinologia e Metabologia (SBEM; Brazilian Society of Endocrinology and Metabolism) was invited to prepare a document following the rules set by the Guidelines Program of the Associação Médica Brasileira (AMB; Brazilian Medical Association). Relevant papers were retrieved from the databases MEDLINE/PubMed, LILACS, and SciELO, and the evidence derived from each article was classified into recommendation levels according to scientific strength and study type. Conclusion An update on the recent scientific literature addressing hypoparathyroidism is presented to serve as a basis for the diagnosis and treatment of this condition in Brazil.


Subject(s)
Humans , Evidence-Based Medicine , Hypoparathyroidism/diagnosis , Hypoparathyroidism/drug therapy , Societies, Medical , Brazil , Hypoparathyroidism/etiology
8.
Rev. bras. epidemiol ; 20(3): 526-536, Jul.-Set. 2017. tab
Article in Portuguese | LILACS | ID: biblio-898606

ABSTRACT

RESUMO: Introdução: A síndrome da lipodistrofia do HIV é caracterizada por alterações no metabolismo e na composição corporal, que aumentam o risco cardiovascular de pessoas vivendo com HIV/AIDS (PVHA) em uso da terapia antirretroviral de alta potência (TARV). Objetivo: Avaliar a prevalência de lipodistrofia e de alterações do metabolismo de lipídios e glicose em PVHA em uso da TARV. Métodos: Para avaliação antropométrica foram aferidos peso, estatura e circunferência abdominal (CA). Para avaliação da lipodistrofia foi realizado o exame físico (subjetivo) e o exame (objetivo) de absortometria com raios X de dupla energia (DEXA) por meio da razão de massa gorda (RMG). Foram também realizados exames de lipidograma e glicemia de jejum e utilizados os critérios sugeridos pelo The National Cholesterol Education Program III para classificação de alterações metabólicas. Resultados: A amostra final consistiu em 262 pacientes com idade média de 44,3 ± 10,2 anos. A lipodistrofia, de acordo com o exame físico, esteve presente em 47,7% (IC95% 41,7 - 53,8) dos pacientes, enquanto pela RMG (DEXA) sua prevalência foi de 40,8% (IC95% 33,1 - 48,5). A maioria (53,0%; IC95% 47,0 - 59,1) dos pacientes apresentou aumento de adiposidade abdominal segundo a CA. As alterações metabólicas mais presentes foram o HDL reduzido (67,6%; IC95% 61,9 - 73,2) e a hipertrigliceridemia (55,7%; IC95% 49,7 - 61,7). Conclusões: A alta prevalência de lipodistrofia e alterações do metabolismo de lipídios e glicose evidenciam a importância da intervenção precoce nesse grupo de pacientes para prevenir complicações cardiovasculares.


ABSTRACT: Introduction: The HIV lipodystrophy syndrome is characterized by changes in metabolism, and body composition that increase cardiovascular risk of people living with HIV/AIDS (PLWHA) using highly active antiretroviral therapy (HAART). Objective: To assess the prevalence of lipodystrophy and changes in lipid and glucose metabolism in PLWHA in use of HAART. Methods: For the anthropometric evaluation we measured weight, height and abdominal circumference (AC). For the lipodystrophy evaluation we conducted physical examination (subjective) and the (objective) examination of absorptiometry with X-ray dual energy (DEXA) by fat mass ratio (FMR). We also conducted lipid profile tests and fasting glucose and used the criteria suggested by The National Cholesterol Education Program III for metabolic disorders classification. Results: The final sample consisted of 262 patients with a mean age of 44.3 ± 10.2 years. Lipodystrophy, according to the physical examination, was present in 47.7% (95%CI 41.7 - 53.8) of patients, while the prevalence using FMR (DEXA) was 40.8% (95%CI 33.1 - 48.5). Most (53.0%; 95%CI 47.0 - 59.1) of the patients showed increased abdominal adiposity according to AC. The most prevalent metabolic alterations were reduced HDL (67.6%; 95%CI 61.9 - 73.2) and hypertriglyceridemia (55.7%; 95%CI 49.7 - 61.7). Conclusion: The high prevalence of lipodystrophy and changes in lipid and glucose metabolism show the importance of early intervention in this group of patients to prevent cardiovascular complications.


Subject(s)
Humans , Male , Female , Adult , HIV Infections/metabolism , HIV Infections/drug therapy , Adipose Tissue , Antiretroviral Therapy, Highly Active , Lipid Metabolism , Glucose/metabolism , Lipodystrophy/epidemiology , HIV Infections/complications , Prevalence , Cross-Sectional Studies , Acquired Immunodeficiency Syndrome/metabolism , Lipodystrophy/etiology
9.
Rev. bras. ginecol. obstet ; 39(3): 102-109, Mar. 2017. tab, graf
Article in English | LILACS | ID: biblio-843921

ABSTRACT

Abstract Objectives To assess the prevalence of hypovitaminosis D, altered arterial blood pressure, and serum levels of glucose and lipids in community-dwelling women in the city of Ribeirão Preto, in the southeast of Brazil. Methods Thiswas a cross-sectional studyof women aged40-70years old.Calciumintake and level of sun exposure were assessed by means of a questionnaire. A blood sample was used to determine glucose, lipid profile and 25-hydroxyvitaminD(25[OH]D) concentration. Results Ninety-one women were enrolled (age = 54.2 ± 7.1 years). Themean serum 25(OH)D concentration was 25.7 ± 8.9 ng/mL. A total of 24 (26.4%) women had 25 (OH)D levels < 20 ng/mL. Seventy women (76.9%) had 25(OH)D levels < 30 ng/mL. Seventy-five women (90.4%) had inadequate calcium intake, and 61 women (67%) had appropriate sun exposure, 49 of whom (80.3%) had serum 25(OH)D levels < 30 ng/mL. Conclusion This study indicates that even in community-dwelling women, living in a city with high sun exposure, serum levels of 25(OH)D > 30 ng/ml are hardly reached. Thus, it is probable that other intrinsic factors besides sun exposure may regulate the levels of vitamin D.


Resumo Objetivos Estimar a prevalência de hipovitaminose D, hipertensão arterial, e níveis séricos de glicose e perfil lipídico em uma comunidade de mulheres de Ribeirão Preto, no Sudeste brasileiro. Métodos Estudo transversal com mulheres de 40 a 70 anos de idade, submetidas a um questionário para determinar ingestão diária de cálcio e nível de exposição solar, e coleta de sangue para determinar glicose, perfil lipídico e concentração de 25- hidroxivitamina D (25[OH]D). Resultados Noventa e uma mulheres foram incluídas (idade = 54,2 ± 7,1 anos). O nível sérico médio de 25(OH)D foi 25,7 ± 8,9 ng/mL. Um total de 24 (26,4%) mulheres teve níveis de 25(OH)D < 20 ng/mL. Setenta mulheres (76.9%) tiveram níveis de 25 (OH)D < 30 ng/mL. Setenta e uma mulheres (90.4%) tiveram uma ingesta inadequada de cálcio e 61 mulheres (67%) tiveram exposição solar adequada; 49 das quais (80.3%) tiveram níveis séricos de 25(OH)D < 30 ng/mL. Conclusão Este estudo indica que mesmo morando em uma cidade com exposição solar adequada, níveis séricos de 25(OH)D > 30 ng/mL dificilmente são atingidos por mulheres climatéricas. Logo, é provável que outros fatores intrínsecos podem regular o nível de vitamina D.


Subject(s)
Humans , Female , Adult , Middle Aged , Aged , Sunlight , Vitamin D Deficiency/epidemiology , Vitamin D/analogs & derivatives , Brazil/epidemiology , Cross-Sectional Studies , Prevalence , Vitamin D/blood
10.
J. bras. nefrol ; 38(4): 466-469, Oct.-Dec. 2016. tab
Article in English | LILACS | ID: biblio-829073

ABSTRACT

Abstract Nowadays vitamin D (25-OHD) deficiency is supposed to be a global epidemic condition. Expectedly, vitamin D measurement and intake exponentially increased in Brazil in this decade. Although the benefit of vitamin D to general health is still in debate, its indiscriminate use potentially may lead to enhance the incidence of vitamin D intoxication, which is considered a rare disorder. We report a case of a 70 year old diabetic male with chronic renal disease (blood creatinine of 1.6 mg/dL) who progressed suddenly to acute kidney injury (blood creatinine of 5.7 mg/dL) associated with hypercalcemia and high blood levels of vitamin D. Vitamin D and calcitriol were discontinued and hypercalcemia was managed by hydration followed by furosemide. Thereafter, disodium pamidronate was administered and the patient did not undergo on dialysis. It took approximately 14 months to normalize 25-OHD levels and blood creatinine returned to basal levels only after 24 months. The indicated labeling dosage was 2000 IU, but most likely the vitamin D manipulated preparation was higher as the vitamin D blood levels were very high. Although rare, vitamin D intoxication is becoming more frequent as the patients use frequently manipulated preparations that could be subject to errors in the manufacturing and labeling of the tablets or capsules. The present report alerts to the potential increase in the incidence of severe vitamin D intoxication due to the frequent use of this secosteroid as a nutritional supplement. At the same time, it is necessary to improve regulation on the nutrient supplement market.


Resumo Atualmente, muitos brasileiros têm utilizado vitamina D (25-OHD) como suplemento vitamínico para prevenção de diversas doenças crônicas, apesar da falta de dados científicos consistentes sobre o papel deste secosteroide na prevenção de doenças que não as do metabolismo mineral. A intoxicação por vitamina D é rara, mas devido ao seu uso indiscriminado tem ocorrido com maior frequência. Nesse relato, um homem diabético de 70 anos de idade com doença renal crônica (creatinina sérica de 1,6 mg/dL) passou a fazer uso de colecalciferol e calcitriol para recomposição dos níveis de 25-OHD, que eram de 16 ng/mL. O mesmo desenvolveu quadro de lesão renal aguda (creatinina = 5,7 mg/dL), após 45 dias. Este processo emergiu em paralelo ao surgimento de hipercalcemia e níveis circulantes elevados de vitamina D. Foram suspensas a administração de vitamina D e calcitriol, a hipercalcemia foi tratada com hidratação endovenosa, seguida de diurético de alça e posteriormente pamidronato. O paciente, que havia sido encaminhado para diálise, não necessitou desse tratamento. Os níveis de 25-OHD voltaram ao normal 14 meses após a sua suspensão, e os níveis de creatinina voltaram aos patamares anteriores 24 meses após esse evento. A dose prescrita de vitamina D correspondeu a 2000 UI/dia, a qual não é considerada inadequada segundo recomendações atuais. Existe, no entanto, na literatura controvérsia quanto à sensibilidade individual à vitamina D. Não pode ser descartado o uso inapropriado pelo paciente e nem eventual erro de manipulação. Embora raro, o quadro de intoxicação por vitamina D é grave e potencialmente pode levar a complicações clínicas irreversíveis.


Subject(s)
Humans , Male , Aged , Vitamin D/poisoning , Vitamins/poisoning , Dietary Supplements/poisoning , Acute Kidney Injury/chemically induced , Hypercalcemia/chemically induced , Acute Kidney Injury/physiopathology , Hypercalcemia/physiopathology , Kidney/physiopathology
11.
Arch. endocrinol. metab. (Online) ; 59(3): 252-258, 06/2015. tab, graf
Article in English | LILACS | ID: lil-751308

ABSTRACT

Objective Bone loss has been established as a major extra-intestinal complication of short bowel syndrome (SBS). The purpose of this study was to correlate bone mineral density (BMD) with body mass index (BMI), serum vitamin and mineral levels in patients with SBS.Material and methods The study was conducted on 13 patients (8 male and 5 female, 54.7 ± 11.4 years) with SBS (residual small bowel length of 10 to 100 cm). We determined the food ingestion, anthropometry, serum levels of vitamins C, A, D, E and K, as well as serum and urinary levels of phosphorus and calcium. BMD was measured by dual-energy x-ray absorptiometry (DXA).Results Osteopenia and osteoporosis was diagnosed in all but one SBS patient. Serum levels of vitamin D were low in all volunteers. Sixty-one percent of patients had vitamin E deficiency; hypovitaminosis A and C occurred in one subject. BMI and C, E and K vitamin serum levels correlated with T-score of BMD.Conclusions Osteopenia and osteoporosis were common in SBS patients. There was a correlation between BMD and the serum levels of vitamins C, E and K, an indicative that such vitamins may influence bone health. Arch Endocrinol Metab. 2015;59(3):252-8.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Ascorbic Acid/blood , Body Mass Index , Bone Density/physiology , Short Bowel Syndrome/physiopathology , Vitamin E/blood , Vitamin K/blood , Absorptiometry, Photon , Avitaminosis/complications , Bone Diseases, Metabolic/etiology , Cross-Sectional Studies , Calcium/analysis , Energy Intake/physiology , Hospitalization , Osteoporosis/etiology , Phosphorus/analysis , Reference Values , Short Bowel Syndrome/blood , Short Bowel Syndrome/complications , Time Factors
12.
Rev. nutr ; 26(2): 225-232, Mar.-Apr. 2013. graf, tab
Article in English | LILACS | ID: lil-675995

ABSTRACT

OBJECTIVE: In view of the practical need to use equations for the evaluation of energy expenditure in HIV-infected patients, the objective of the present study was to determine the concordance between the energy expenditure values obtained by indirect calorimetry as the gold standard and those obtained by predictive equations elaborated from data for the healthy population: Harris-Benedict, Schofield and Cunningham, and by equations elaborated from data for HIV-infected patients: Melchior (1991-1993). METHODS: The study was conducted at the Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto on 32 HIV-infected men under treatment with highly active antiretroviral therapy. Resting energy expenditure was measured by indirect calorimetry and estimated on the basis of measurement of O2 consumption and CO2 production. RESULTS: Statistical analysis revealed weak concordance for the Harris-Benedict (0.38) and Cunningham (0.34) equations and satisfactory concordance for the Schofield equation (0.47). Only the two Melchior equations (1991 and 1993) showed strong concordance with the values obtained by indirect calorimetry (0.63 and 0.66, respectively) and could be used in practice. CONCLUSION: The best equations seem to be population-specific, such as the Melchior equations elaborated for HIV-infected patients.


OBJETIVO: Frente à necessidade prática da utilização de equações para avaliar gasto energético em portadores do HIV, o presente estudo avaliou a concordância dos valores de gasto energético obtidos pelo padrão ouro de calorimetria indireta com equações preditivas desenvolvidas a partir de população saudável: Harris-Benedict, Schofield e Cunningham e equações desenvolvidas a partir de portadores do HIV: Melchior (1991 a 1993). MÉTODOS: O estudo foi realizado no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, com 32 homens portadores do HIV em terapia antirretroviral de alta potência. O gasto energético de repouso foi medido por calometria indireta e estimado a partir de medida de consumo de O2 e produção de CO2. RESULTADOS: De acordo com análise estatística, a concordância foi fraca para equações de Harris-Benedict (0,38) e Cunningham (0,34) e satisfatória para Schofield (0,47). Apenas as duas equações de Melchior apresentaram forte concordância com valores obtidos por calometria indireta (respectivamente 0,63 e 0,66) e poderiam ser utilizadas na prática. CONCLUSÃO:: As melhores equações parecem ser população específica, como as de Melchior, desenvolvidas para portadores do HIV.


Subject(s)
Humans , Male , Adolescent , Young Adult , Middle Aged , HIV , Calorimetry, Indirect/methods , Energy Metabolism
13.
Coluna/Columna ; 12(1): 21-24, 2013. ilus, tab
Article in Portuguese | LILACS | ID: lil-673284

ABSTRACT

OBJETIVO: Analisar experimentalmente a influência do macheamento do orifício piloto nas propriedades mecânicas e na interface osso-implante do parafuso cervical anterior. MÉTODOS: Oito carneiros da raça Santa Inês deslanados foram utilizados no estudo. Nos segmentos vertebrais cervicais de C2-C7 foram realizados orifícios piloto de 2,5mm, de ambos os lados da vértebra. No lado direto da vértebra foi realizado o macheamento previamente a inserção do parafuso cortical de 3,5mm, e no lado esquerdo o implante foi colocado sem o macheamento do orifício piloto. Foram realizados ensaios mecânicos para avaliar a força de arrancamento dos implantes e estudo histomorfométrico da interface osso-implante na fase aguda e oito semanas após a colocação dos implantes. O torque de inserção foi mensurado durante a colocação dos implantes. RESULTADOS: O torque de inserção e a resistência ao arrancamento dos implantes foram maiores nos implantes colocados sem o macheamento do orifício piloto. A interface osso-implante apresentou maior área de contato ósseo e maior área óssea no interior da rosca do implante nos parafusos implantados sem o macheamento prévio. Não foi observado diferença na área óssea fora do passo de rosca do implante. CONCLUSÕES: O macheamento do orifício piloto reduz o torque de inserção e a resistência ao arrancamento do implante na fase aguda e crônica, e reduz a área de contato osso-implante e área de osso no interior do passo de rosca.


OBJECTIVE: Experimentally analyze the influence of the pilot hole tapping on the mechanical properties and the bone-implant interface of anterior cervical screw. METHODS: Eight shorn Santa Inês sheep were used in the study. In cervical segments C2-C7 of the column 2.5mm pilot holes were made on both sides of the vertebra. On the right side of the vertebra tapping was done before the insertion of the cortical screw of 3.5mm, and on the left side the implant was placed without tapping the pilot hole. Mechanical assays were performed to assess the strength of pullout as well as a histomorphometric study of bone-implant interface during the acute phase and eight weeks after implant placement. The insertion torque was measured during implant placement. RESULTS: The insertion torque and pullout strength were higher for implants placed without tapping the pilot hole. The bone-implant interface showed greater area of bone contact and greater bone area within the implant thread on the screws implanted without prior tapping. No differences were observed in the bone outside the thread pitch of the implant. CONCLUSIONS: Tapping the pilot hole reduces insertion torque and pullout strength of the implant in both acute and chronic phases, and reduces the area of bone-implant contact and the bone area within the thread pitch.


OBJETIVO: Para estudiar experimentalmente la influencia del taladramiento del agujero piloto sobre las propiedades mecánicas y la interfaz hueso-implante del tornillo cervical anterior. MÉTODOS: Ocho ovejas Santa Ines fueron utilizadas en el estudio. En los segmentos vertebrales cervicales C2-C7 se hicieron agujeros pilotos de 2,5 mm en ambos lados de la vértebra. En el lado derecho de la vértebra el taladramiento se hizo antes de la inserción del tornillo cortical de 3,5 mm, y en el lado izquierdo el implante fue colocado sin el taladramiento del agujero piloto. Se realizaron ensayos mecánicos para evaluar la fuerza de retirada y el estudio histomorfométrico de la interfase hueso-implante en la fase aguda y ocho semanas después de la colocación del implante. El torque de inserción se midió durante la colocación del implante. RESULTADOS: La fuerza de torsión de la inserción y la resistencia a la extracción fueron más altas en los implantes colocados sin el taladramiento del agujero piloto. La interfaz hueso-implante presentó mayor área de contacto con el hueso y mayor área de hueso dentro de la rosca del implante en los tornillos implantados sin taladramiento previo. No se observaron diferencias en el hueso fuera del paso de la rosca del implante. CONCLUSIONES: El taladramiento del agujero piloto reduce el par de torsión de inserción y la resistencia a la extracción del implante en las fases aguda y crónica, y reduce el área de contacto hueso-implante y el área ósea en el interior del paso de la rosca.


Subject(s)
Animals , Spinal Fractures , Bone Screws , Fracture Fixation , Histology
14.
Rev. nutr ; 24(6): 845-852, nov.-dez. 2011. ilus, tab
Article in Portuguese | LILACS | ID: lil-618431

ABSTRACT

OBJETIVO: Este estudo teve como objetivo avaliar a associação do estado nutricional com a força muscular de preensão manual e a densidade mineral óssea em idosos do sexo masculino. MÉTODOS: Participaram do estudo 41 idosos do sexo masculino, sendo 20 eutróficos (peso: M=69,6, DP=8,4; índice de massa corporal: M=25,7, DP=2,2) e 21 desnutridos (peso: M=50,9, DP=6,1; índice de massa corporal: M=18,7, DP=1,8), classificados subjetivamente segundo a Mini Avaliação Nutricional. A avaliação antropométrica incluiu peso corporal, altura, circunferência do braço e da panturrilha. A composição corporal foi avaliada pelo método de absorciometria por dupla emissão de Raios X, e a ocorrência de osteoporose foi definida de acordo com os critérios estabelecidos pela Organização Mundial da Saúde. A força muscular foi avaliada pelo dinamômetro de mão. RESULTADOS: O grupo desnutrido apresentou valores expressivamente menores dos parâmetros antropométricos e de com-posição corporal em relação ao grupo eutrófico (p<0,005). Além disso, a ocorrência de osteoporose foi signifi-cativamente maior (p<0,01) no grupo desnutrido em todas as regiões estudadas: colo do fêmur, quadril total e coluna. A força muscular de preensão manual dos idosos desnutridos foi significativamente menor que a dos idosos eutróficos (M=23,1, DP=6,8 e M=30,3, DP=8,4, respectivamente; p<0,005). CONCLUSÃO: A desnutrição está associada à menor força muscular e à diminuição da densidade mineral óssea em idosos do sexo masculino.


OBJECTIVE: The present study investigated the possible association of nutritional status with handgrip strength and bone mineral density in elderly men. METHOODS: The study included 41 elderly males of which 20 were well-nourished (weight: M=69.6, SD=8.4kg; BMI: M=25.7, SD=2.2) and 21 were malnourished (weight: M=50.9, SD=6.1kg; BMI: M=18.7, SD=1.8). They were subjectivity classified by the Mini Nutritional Assessment. Anthropometric measurements included weight, height and arm and calf circumferences. Body composition was determined by dual energy x-ray absorptiometry and presence of osteoporosis was determined according to the World Health Organization's criteria. Muscle strength was assessed by a handheld dynamometer. RESULTS: The malnourished group presented significantly lower anthropometric and body composition measurements than the well-nourished group (p<0.005). Furthermore, the occurrence of osteoporosis was significantly higher (p<0.01) among malnourished individuals in all studied body areas: femoral neck, total hip and spine. The handgrip strength of malnourished individuals was significantly lower than that of well-nourished individuals (M=23.1, SD=6.8 and M=30.3, SD=8.4, respectively; p<0.005). CONCLUSION: Malnutrition is associated with lower muscle strength and low bone mineral density in elderly men.


Subject(s)
Humans , Male , Aged , Aged, 80 and over , Nutrition Assessment , Body Composition , Malnutrition/complications , Aging , Nutritional Status , Elderly Nutrition
15.
Rev. bras. ortop ; 45(3): 290-294, maio-jun. 2010. ilus, graf, tab
Article in Portuguese | LILACS | ID: lil-555957

ABSTRACT

OBJETIVO: Avaliar a influência do macheamento do orifício piloto associado às outras variáveis como o seu diâmetro em relação ao diâmetro interno do parafuso e o modo de preparo no torque de inserção, na resistência ao arrancamento dos parafusos utilizados para a fixação anterior da coluna cervical. MÉTODO: Vinte corpos de prova de poliuretana e 30 vértebras torácicas (T1-T5) foram testadas. Em cada corpo de prova foram realizados quatro orifícios, sendo dois com diâmetro de 2,0mm e dois com 2,5mm. Esses orifícios foram confeccionados com broca ou sonda, de acordo com o grupo experimental. O macheamento do orifício piloto era ou não realizado, dividindo desse modo o grupo experimental em subgrupos iguais. Foram formados oito grupos experimentais (quatro utilizando poliuretana e quatro utilizando vértebras de carneiro). Parafusos corticais com 3,5mm de diâmetro externo e 14mm de comprimento foram inseridos nos orifícios piloto. O torque de inserção foi mensurado durante a implantação dos parafusos e, em seguida, foram realizados ensaios mecânicos de arrancamento em máquina universal de testes Emic®, softwareTesc 3.13, célula de carga de 1.000N, velocidade de aplicação de força de 0,2mm/min, pré-carga de 5N e tempo de acomodação de 10 segundos. A propriedade avaliada nos ensaios mecânicos foi a força máxima de arrancamento. RESULTADOS E CONCLUSÃO: O macheamento do orifício piloto reduziu significativamente o torque de inserção e a força de arrancamento dos parafusos em todos os grupos experimentais.


OBJECTIVE: To determine the effect of pilot hole tapping, together with other variables such as pilot hole diameter, in relation to inner screw diameter and preparation mode, on the insertional torque and pullout strength of the screws used for anterior fixation of the cervical spine. METHODS: Twenty polyurethane test bodies and 30 thoracic vertebrae (T1-T5) were tested. Four holes were drilled into each test body, two of them with a diameter of 2.0 mm and two with a diameter of 2.5 mm. The holes were drilled with a bit or probe according to the experimental group. Pilot hole tapping was or was not done, dividing the experimental group into equal subgroups. Eight experimental groups were formed, four of which used polyurethane specimens and four used sheep vertebrae. Cortical screws 3.5 mm in outer diameter and 14 mm long were inserted into the pilot holes. Insertional torque was measured during screw implantation and mechanical assays were then performed using an Emic® universal testing machine. Tesc 3.13 software was used for data analysis. Load cells with a capacity of 1000 N, were used and the rate of force application was 0.2mm/min. The mechanical property evaluated was the maximum pullout force of the screws. RESULTS AND CONCLUSIONS: Pilot hole tapping significantly decreased insertional torque and pullout force in all experimental groups.


Subject(s)
Animals , Biomechanical Phenomena , Bone Screws , Orthopedic Fixation Devices , Sheep , Spine , Torque
16.
Rev. bras. ortop ; 44(5): 415-419, set.-out. 2009. ilus, graf, tab
Article in Portuguese | LILACS | ID: lil-531475

ABSTRACT

OBJETIVO: Avaliar a influência do desenho do parafuso (autoperfurante e automacheante) e do macheamento do orifício-piloto sobre o torque de inserção e a força de arrancamento dos parafusos utilizados para a fixação anterior da coluna cervical. MÉTODO: Quarenta parafusos automacheantes e 20 autoperfurantes foram inseridos em 10 modelos artificiais de osso (blocos de poliuretana) e 10 vértebras cervicais de carneiro. Os parâmetros estudados foram o torque de inserção e a força de arrancamento. Foram formados três grupos experimentais de acordo com o tipo de preparo do orifício- piloto e o tipo de parafuso utilizado: grupo I - parafuso automacheante com orifício- piloto perfurado e macheado; grupo II - parafuso automacheante com orifício perfurado e não macheado; grupo III - parafuso autoperfurante sem perfuração prévia do orifício- piloto e sem o macheamento. Nos grupos I e II a perfuração do orifício-piloto foi realizada por meio de broca de 3mm de diâmetro e o macheamento, com 4mm. O torque de inserção foi mensurado durante a implantação dos parafusos e, em seguida, foram realizados ensaios mecânicos em máquina universal de testes para avaliar a força de arrancamento dos parafusos. RESULTADOS: O macheamento e a perfuração do orifício- piloto reduziram significativamente o torque de inserção e a força de arrancamento. CONCLUSÃO: O torque de inserção e a força de arrancamento dos parafusos autoperfurantes foram significativamente maiores quando comparado com os dos parafusos automacheantes inseridos após o macheamento do orifício-piloto.


OBJECTIVE: To assess if the screw design (self-drilling/self-tapping) and the pilot hole tapping could affect the insertion torque and screw pullout strength of the screw used in anterior fixation of the cervical spine. METHODS: Forty self-tapping screws and 20 self-drilling screws were inserted into 10 models of artificial bone and 10 cervical vertebrae of sheep. The studied parameters were the insertion torque and pullout strength. The following groups were created: Group I - self-tapping screw insertion after pilot hole drilling and tapping; Group II - self-tapping screw insertion after pilot hole drilling without tapping; Group III - self-drilling screw insertion without drilling and tapping. In Groups I and II, the pilot hole had 14.0 mm in depth and was made with a 3mmn drill, while tapping was made with a 4mm tap. The insertion torque was measured and the pullout test was performed. The comparison between groups was made considering the mean insertion torque and the maximum mean pullout strength with the variance analysis (ANOVA; p< 0.05). RESULTS: Previous drilling and tapping of pilot hole significantly decreased the insertion torque and the pullout strength. CONCLUSION: The insertion torque and pullout strength of self-drilling screws were significantly higher when compared to self-tapping screws inserted after pilot hole tapping.


Subject(s)
Biomechanical Phenomena , Bone Screws , Orthopedic Fixation Devices , Spine
17.
Coluna/Columna ; 8(3): 310-314, jul.-set. 2009. ilus, tab
Article in Portuguese | LILACS | ID: lil-538737

ABSTRACT

OBJETIVO: comparar o novo parafuso travado na placa cervical (CSLP) automacheante com o parafuso convencional cortical automacheante utilizado na fixação da placa cervical anterior, por meio da análise do torque de inserção e da resistência ao arrancamento dos implantes. MÉTODOS: 15 parafusos corticais automacheantes e 15 parafusos CSLP automacheantes foram inseridos em 15 modelos artificiais de osso (poliuretana) e 15 vértebras cervicais de carneiro. Os parâmetros estudados foram o torque de inserção e a força de arrancamento. Foram formados dois grupos experimentais, de acordo com o tipo de parafuso utilizado: Grupo I, com parafuso cortical automacheante; Grupo II, com parafuso CSLP automacheante. O orifício-piloto foi perfurado com 10,0 mm de profundidade, por meio de broca com diâmetro de 2,5 mm (Grupo I) e 3,0 mm (Grupo II). O torque de inserção foi mensurado durante a implantação dos parafusos e, em seguida, foram realizados ensaios mecânicos em máquina universal de testes, para avaliar a força de arrancamento dos implantes. RESULTADOS: os parafusos automacheantes CSLP apresentaram valores do torque de inserção e resistência ao arrancamento maiores que os parafusos corticais automacheantes. CONCLUSÃO: o desenho do parafuso CSLP influencia o seu torque de inserção e resistência ao arrancamento, sendo a avaliação desses parâmetros superiores aos parafusos corticais automacheantes.


OBJECTIVE: compare the new self-tapping cervical spine locking plate (CSLP) screw with traditional self-tapping cortical screw used in anterior cervical locking plates in terms of insertion torque and pullout strength. METHODS: 15 traditional self-tapping cortical screws and 15 new self-drilling CSLP screws were inserted into 15 models of artificial bone (polyurethane) and 15 cervical vertebrae of sheep. The studied parameters were the insertional torque and pullout strength. The following groups were created, in agreement with the type of screw used: Group I, of self-tapping cortical screw; and Group II, with self-tapping CSLP screw. The pilot hole had 10.0 mm in depth and was made with a 2.5 mm (Group I) and 3.0 mm (Group II) drill. The insertional torque was measured and the pullout test was performed. RESULTS: the CSLP self-tapping screw presented a higher insertional torque and pullout strength compared to cortical self-tapping screws. CONCLUSION: the thread design of CSLP screw influenced the insertional torque and pullout resistance, and the evaluation of these parameter were superior to cortical self-tapping screw.


OBJETIVO: comparar el nuevo tornillo cervical spine locking plate (CSLP) autoterrajante con el convencional tornillo cortical autoterrajante utilizado en la fijación de la placa cervical anterior, por medio del análisis del torque de inserción y de la resistencia al arrancamiento de los implantes. MÉTODOS: quince tornillos corticales autoterrajante y 15 tornillos CSLP autoterrajante fueron inseridos en 15 modelos artificiales de hueso (poliuretana) y 15 vértebras cervicales de oveja. Los parámetros estudiados fueron el torque de inserción y la fuerza de arrancamiento. Fueron formados dos grupos experimentales de acuerdo con el tipo de tornillo utilizado: Grupo I-Tornillo cortical autoterrajante; Grupo II-tornillo CSLP autoterrajante. El orificio-piloto fue perforado con 10.0 mm de profundidad por medio de una broca con diámetro de 2.5 mm (Grupo I) y 3.0 mm (Grupo II). El troque de inserción fue medido durante la implantación de los tornillos y en seguida fueron realizados ensayos mecánicos en máquina universal de test para evaluar la fuerza de arrancamiento de los implantes. RESULTADOS: los tornillos autoterrajante CSLP presentaron valores del torque de inserción y resistencia al arrancamiento mayores que los tornillos corticales autoterrajante. CONCLUSIÓN: el diseño del tornillo CSLP influye en su troque de inserción y resistencia al arrancamiento, siendo la evaluación de estos parámetros superiores a los tornillos corticales autoterrajante.


Subject(s)
Humans , Biomechanical Phenomena , Bone Screws , Spine/surgery , General Surgery , Torque
18.
São Paulo med. j ; 120(1): 23-27, jan. 2002. ilus, tab
Article in English | LILACS | ID: lil-303894

ABSTRACT

CONTEXT: The association between psoriasis and hypoparathyroidism has been reported by several authors, and it has been suggested that abnormalities in calcium homeostasis may be involved in the development or exacerbation of psoriasis. However, so far there have only been two reports of pseudohypoparathyroidism associated with psoriasis. OBJECTIVE: To describe the familial occurrence of this association for the first time. CASE REPORTS: Two siblings with psoriasis associated with pseudohypoparathyroidism were presented. The first patient was a 24-year-old white male with disseminated erythrodermic pustular psoriasis that began 2 months before admission. He had had a history of mental retardation, recurrent otitis, seizures and arthralgia from the age of 11 years onwards. He presented the characteristic phenotype of Albright osteodystrophy: short stature, obesity, round facies, broad forehead, short neck and brachydactylia. He adopted a position of flexed limbs and showed proximal muscle weakness and a positive Trousseau sign. He had clinical signs of hypocalcemia (0.69 mmol/l ionized calcium and 3.2 mg/dl total calcium), hyperphosphatemia (6.6 mg/dl), hypomagnesemia (1.0 mEq/l), hypoalbuminemia (3.1 g/dl), normal serum intact PTH levels (45.1 pg/ml), primary hypothyroidism (13.2 mU/ml TSH, and 4.7 mg/dl total T4), hypergonadotrophic hypogonadism (116.0 ng/ml LH, 13.2 mU/ml FSH and 325.0 ng/dl testosterone), osteoporosis, and diffuse calcifications in soft tissues and in the central nervous system. The second case was a 14-year-old white girl with a history of psoriasis vulgaris from the age of five years onwards, and antecedents of mental retardation. She presented signs of Albright osteodystrophy (short stature, round facies, obesity, short neck, brachydactylia), hypocalcemia (ionized calcium of 1.08 mmol/l and total calcium of 6.7 mg/dl) hyperphosphatemia (9.4 mg/dl), elevated serum PTH levels (223.0 pg/ml), osteoporosis, and hypergonadotrophic hypogonadism (7.0 mU/ml LH, 9.3 mU/ml FSH and undetectable estradiol levels)


Subject(s)
Humans , Male , Female , Adolescent , Adult , Pseudohypoaldosteronism , Psoriasis/etiology , Calcium Carbonate , Pseudohypoaldosteronism , Cholecalciferol , Abnormalities, Multiple , Nuclear Family , Psoriasis/genetics , Psoriasis/drug therapy
SELECTION OF CITATIONS
SEARCH DETAIL