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1.
Biomed Mater Eng ; 35(5): 415-423, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39121111

RESUMO

BACKGROUND: Tissue engineering seeks to improve, maintain, or replace the biological functions of damaged organs or tissues with biological substitutes such as the development of scaffolds. In the case of bone tissue, they must have excellent mechanical properties like native bone. OBJECTIVE: In this work, three geometric models were designed for scaffolds with different structure lattices and porosity that could be biomechanically suitable and support cell growth for trabecular bone replacement applications in tissue engineering and regenerative medicine to the proximal femur area. METHODS: Geometries were designed using computer-aided design (CAD) software and evaluated using finite element analysis in compression tests. Three loads were considered according to the daily activity: 1177 N for slow walking, 2060 N for fast walking, and 245.25 N for a person in a bipedal position. All these loads for an adult weight of 75 kg. For each of them, three biomaterials were assigned: two polymers (poly-glycolic acid (PGA) and poly-lactic acid (PLA)) and one mineral (hydroxyapatite (HA)). 54 tests were performed: 27 for each of the tests. RESULTS: The results showed Young's modulus (E) between 1 and 4 GPa. CONCLUSION: If the resultant E is in the range of 0.1 to 5 GPa, the biomaterial is considered an appropriate alternative for the trabecular bone which is the main component of the proximal bone. However, for the models applied in this study, the best option is the poly-lactic acid which will allow absorbing the acting loads.


Assuntos
Desenho Assistido por Computador , Análise de Elementos Finitos , Engenharia Tecidual , Alicerces Teciduais , Alicerces Teciduais/química , Humanos , Engenharia Tecidual/métodos , Durapatita/química , Módulo de Elasticidade , Bioimpressão/métodos , Poliésteres/química , Porosidade , Simulação por Computador , Materiais Biocompatíveis/química , Substitutos Ósseos/química , Ácido Poliglicólico/química , Impressão Tridimensional , Teste de Materiais , Osso e Ossos
2.
Int. j. morphol ; 42(3): 607-613, jun. 2024. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1564594

RESUMO

SUMMARY: Binge drinking in adolescents has a negative effect on the developing skeleton and the attainment of peak bone mass. Our study aimed to examine the effect of binge drinking on the growth and functional integrity of the adolescent Sprague Dawley rat mandible and to determine if a dosage of 1.5 g/kg is sufficient to produce a binge-model of consumption. A total of eight 7-week-old adolescent (male) Sprague Dawley rats were randomly placed into 4 groups with two rats each: 1-week alcohol-exposed rats, 1-week pair- fed control rats, 4-week alcohol-exposed rats and 4-week pair-fed control rats. The alcohol exposed groups were administered a single daily dose via oral gavage of 1.5 g/kg of 20 % alcohol 3 days a week (alternate days) for 7 or 28 days. The pair-fed control groups were administered a caloric equivalent dose of maltose dextrin via oral gavage on the same days as the alcohol-exposed rats. The one-week alcohol exposed, and control rats were terminated on day 7 and the four-week alcohol exposed and control rats on day 28. The mandibles were dissected out and osteometric measurements determined using a digital vernier caliper. Bones were scanned using a 3D-microCT scanner (Nikon XTH 255L). Biomechanical tests were done using a Shimadzu universal testing machine. Differences observed were regarding mandibular osteometry, which showed a reduced height in the central portion of the alveolar bone (Al'-Me), and an increase in the height of the condylar head (Cd-Ag) in the 1-week alcohol-exposed rats when compared to the 1-week pair-fed control rats. No other differences were noted. Lack of significant changes seen between the alcohol and pair-fed control groups in both acute binge and chronic binge exposed rats is likely due to the low dose of alcohol administered to the rats in the study thus a higher dose is proposed.


El consumo excesivo de alcohol en adolescentes tiene un efecto negativo en el desarrollo del esqueleto y en la consecución de la masa ósea máxima. Nuestro estudio tuvo como objetivo examinar el efecto del consumo excesivo de alcohol sobre el crecimiento y la integridad funcional de la mandíbula de la rata adolescente Sprague Dawley y determinar si una dosis de 1,5 g/kg es suficiente para producir un modelo de consumo compulsivo. Un total de ocho ratas Sprague Dawley adolescentes (machos) de 7 semanas de edad se colocaron aleatoriamente en 4 grupos con dos ratas cada uno: ratas expuestas al alcohol durante 1 semana, ratas de control alimentadas en parejas durante 1 semana, ratas expuestas al alcohol durante 4 semanas, y ratas de control alimentadas en parejas durante 4 semanas. A los grupos expuestos al alcohol se les administró una dosis única diaria mediante sonda oral de 1,5 g/kg de alcohol al 20 % 3 días a la semana (días alternos) durante 7 o 28 días. A los grupos de control alimentados por parejas se les administró una dosis calórica equivalente de maltosa dextrina mediante sonda oral los mismos días que a las ratas expuestas al alcohol. Las ratas expuestas al alcohol durante una semana, las ratas de control al día 7, las ratas expuestas al alcohol durante cuatro semanas y las ratas de control al día 28. Se diseccionaron las mandíbulas y se determinaron las mediciones osteométricas utilizando un calibre vernier digital. Los huesos se escanearon utilizando un escáner 3D-microCT (Nikon XTH 255L). Las pruebas biomecánicas se realizaron utilizando una máquina de pruebas universal Shimadzu. Las diferencias observadas se relacionaron con la osteometría mandibular, que mostró una altura reducida en la porción central del hueso alveolar (Al'-Me) y un aumento en la altura de la cabeza condilar (Cd-Ag) en las ratas expuestas al alcohol durante una semana, en comparación con las ratas control alimentadas en parejas durante una semana. No se observaron otras diferencias. La falta de diferencias significativas entre los grupos de alcohol y de control alimentados en parejas expuestas a ebriedad aguda y ebriedad crónica, probablemente se deba a la baja dosis de alcohol administrada a las ratas en el estudio, por lo que se propone una dosis más alta.


Assuntos
Animais , Masculino , Ratos , Etanol/administração & dosagem , Consumo Excessivo de Bebidas Alcoólicas , Mandíbula/efeitos dos fármacos , Resistência à Tração , Ratos Sprague-Dawley , Concentração Alcoólica no Sangue , Mandíbula/anatomia & histologia
3.
JBRA Assist Reprod ; 28(3): 511-520, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-38801314

RESUMO

Following the advancement of medically assisted reproduction (MAR) technology, and the rationale to extend the culture to the blastocyst stage, performing elective single embryo transfer (eSET), gamete quality and assessment have acquired large relevance in ART. Embryo quality is strictly correlated with gametes quality and culture conditions. Oocyte maturity assessment is therefore imperative for fertilization and embryo evolution. Mature oocytes at the metaphase II stage result in a higher fertilization rate compared to immature oocytes. Indeed, oocyte morphology evaluation represents an important and challenging task that may serve as a valuable prognostic tool for future embryo development and implantation potential. Different grading systems have been reported to assess human embryos, however, in many cases, it is still a major challenge to select the single embryo to transfer with the highest implantation potential. Further, eSET has conferred a challenge to embryologists, who must try to enhance embryo culture and selection to provide an adequate success rate, whilst reducing the overall number of embryos transferred. Above the standard morphological assessment, there are several invasive or non-invasive approaches for embryo selection such as preimplantation genetic testing, time-lapse technology, proteomics and metabolomics, as well as oxygen utilization and analysis of oxidative stress in culture medium. This short review is not designed to be a comprehensive review of all possible features that may influence oocyte quality. It does give, however, a brief overview and describes the prognostic value of the morphological characteristics of human oocytes on their developmental capacity following ART treatments.


Assuntos
Oócitos , Técnicas de Reprodução Assistida , Humanos , Oócitos/fisiologia , Oócitos/citologia , Feminino , Gravidez
4.
Sensors (Basel) ; 24(9)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38733024

RESUMO

The Timed-Up and Go (TUG) test is widely utilized by healthcare professionals for assessing fall risk and mobility due to its practicality. Currently, test results are based solely on execution time, but integrating technological devices into the test can provide additional information to enhance result accuracy. This study aimed to assess the reliability of smartphone-based instrumented TUG (iTUG) parameters. We conducted evaluations of intra- and inter-device reliabilities, hypothesizing that iTUG parameters would be replicable across all experiments. A total of 30 individuals participated in Experiment A to assess intra-device reliability, while Experiment B involved 15 individuals to evaluate inter-device reliability. The smartphone was securely attached to participants' bodies at the lumbar spine level between the L3 and L5 vertebrae. In Experiment A, subjects performed the TUG test three times using the same device, with a 5 min interval between each trial. Experiment B required participants to perform three trials using different devices, with the same time interval between trials. Comparing stopwatch and smartphone measurements in Experiment A, no significant differences in test duration were found between the two devices. A perfect correlation and Bland-Altman analysis indicated good agreement between devices. Intra-device reliability analysis in Experiment A revealed significant reliability in nine out of eleven variables, with four variables showing excellent reliability and five showing moderate to high reliability. In Experiment B, inter-device reliability was observed among different smartphone devices, with nine out of eleven variables demonstrating significant reliability. Notable differences were found in angular velocity peak at the first and second turns between specific devices, emphasizing the importance of considering device variations in inertial measurements. Hence, smartphone inertial sensors present a valid, applicable, and feasible alternative for TUG assessment.


Assuntos
Smartphone , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Reprodutibilidade dos Testes , Acidentes por Quedas/prevenção & controle
5.
Ann Work Expo Health ; 68(6): 605-616, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38606807

RESUMO

OBJECTIVES: To analyze the association between occupational ergonomic risk, personal characteristics, and working conditions with the biomechanical properties of stiffness and muscular tone in the paravertebral muscles of electric pallet jack and forklift operators in the industrial sector. METHODS: A total of 75 industrial sector machine operators were evaluated in 2021. Personal characteristics and working conditions were assessed through a questionnaire. Ergonomic risk was assessed using the Rapid Entire Body Assessment (REBA) method, and biomechanical properties of stiffness and muscular tone were obtained using the Myoton Pro device. Stiffness in paravertebral muscles was compared based on the operated machine and observed ergonomic risk. A multilevel linear regression model was employed to quantify the relationship, with mean differences and 95% CI calculated. RESULTS: Very high ergonomic risk was found in 75% of the electric pallet truck drivers. In this group with the highest ergonomic risk, an association between biomechanical properties and older workers was observed. Additionally, among electric pallet truck drivers, stiffness (mean difference 335.9 N/m, 95% CI: 46.4 (3.4 to 110.0), P < 0.05) and paravertebral muscle tone (mean difference 17.5 Hz, 95% CI: 1.4 (0.1 to 3.4), P < 0.05) showed statistically significant differences in the very high ergonomic risk category compared to the high-risk category. No significant differences were observed in any of the analyzed variables among forklift drivers. CONCLUSIONS: Workers operating electric pallet trucks with very high ergonomic risk according to the REBA method and aged over 40 yr are associated with increased muscle stiffness and tone.


Assuntos
Ergonomia , Postura , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Postura/fisiologia , Fenômenos Biomecânicos/fisiologia , Doenças Profissionais/etiologia , Doenças Profissionais/epidemiologia , Inquéritos e Questionários , Feminino , Fatores de Risco , Tono Muscular/fisiologia
6.
Data Brief ; 54: 110402, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38665154

RESUMO

The data presented in this manuscript describe craniofacial landmark coordinate values, muscle and load moment arm lengths, and mechanical advantage rates for constructing a three-dimensional model of masticatory muscles. Cone-beam computed tomography scans from 30 subjects (aged 12-19 years, 16 females) were used. Thirty-six craniofacial landmarks were identified. Subsequently, the moment arms for 7 muscles and their corresponding load moment arms at incisor and molar positions were determined. Then, the three-dimensional mechanical advantage for each muscle and tooth position was calculated as the ratio of muscle moment arm to load moment arm. This procedure was repeated three times by a main examiner and once by two other examiners. The Friedman test and the square root of the 'method of moments' variance estimator were used to compare data among examiners and calculate random errors, respectively. Although the values for the craniofacial landmark coordinates and biomechanical variables are very close, differences were found between measurements, especially in the interexaminer comparisons. Values served as the basis for reliability (intraclass correlation coefficient) and errors (average mean of absolute differences) analysis in the research paper titled "A three-dimensional method to calculate mechanical advantage in mandibular function: Intra- and interexaminer reliability study," published in the Journal of Orofacial Orthopedics.

7.
J Mot Behav ; 56(4): 453-461, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38439504

RESUMO

The task of transporting objects is a fundamental part of daily living activities. Previous kinematic studies focusing on tasks such as pointing, reach-to-grasp, and drinking have not fully captured the motor behaviors involved in object transportation, including placing a cup on a table or storing items in specific places. Hence, this study aimed to analyze the motor behavior associated with transporting a mug using upper limb kinematic variables. Fifteen healthy adults were instructed to transport an open-handle mug across a table. The kinematic metrics evaluated included object end-error for accuracy, frontal and lateral end-range for precision, movement time, peak velocity, time to peak velocity for control strategy, object path ratio for efficiency, and interjoint coordination. The stability of motor behavior was assessed through a test-retest analysis. The mug transporting task achieved accuracy with a radius <10 mm around the target, a peak velocity of ∼0.4 m/s, a control strategy where acceleration time constituted about 30% of the movement time, and a slightly curved trajectory. The test-retest analysis confirmed stable motor behavior across all kinematic metrics (ICCs > 0.75). Thus, the mug transporting task exhibited unique and stable kinematic characteristics, distinguishing it from non-transport activities and effectively mirroring transporting activities of daily living.


Assuntos
Extremidade Superior , Humanos , Fenômenos Biomecânicos/fisiologia , Masculino , Feminino , Extremidade Superior/fisiologia , Adulto , Adulto Jovem , Desempenho Psicomotor/fisiologia , Movimento/fisiologia
8.
Rev Bras Ortop (Sao Paulo) ; 59(1): e1-e9, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38524725

RESUMO

Since its introduction by Ilizarov, the distraction osteogenesis technique has been used to treat trauma-related conditions, infections, bone tumors, and congenital diseases, either as methods of bone transport or elongation. One of the major dilemmas for the orthopedic surgeon who performs osteogenic distraction is establishing a reproducible method of assessing the progression of the osteogenesis, enabling the early detection of regenerate failures, in order to effectively interfere during treatment, and to determine the appropriate time to remove the external fixator. Several quantitative monitoring methods to evaluate the structural recovery and biomechanical properties of the bone regenerate at different stages, as well as the bone healing process, are under study. These methods can reveal data on bone metabolism, stiffness, bone mineral content, and bone mineral density. The present review comprehensively summarizes the most recent techniques to assess bone healing during osteogenic distraction, including conventional radiography and pixel values in digital radiology, ultrasonography, bone densitometry and scintigraphy, quantitative computed tomography, biomechanical evaluation, biochemical markers, and mathematical models. We believe it is crucial to know the different methods currently available, and we understand that using several monitoring methods simultaneously can be an ideal solution, pointing to a future direction in the follow-up of osteogenic distraction.

9.
Rev Bras Ortop (Sao Paulo) ; 59(1): e82-e87, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38524720

RESUMO

Objective: Rupture of the anterior cruciate ligament (ACL) is one of the most common injuries in athletes and is often associated with damage to anterolateral structures. This combination of injuries presents itself clinically as a high-grade pivot shift test. The hypothesis of this study is that patients with ACL deficiency and high-grade pivot shift test should have an increased internal knee rotation. Methods: Twenty-two patients were tested. After effective spinal anesthesia, two tests were performed with the patient in supine position. First, the bilateral pivot shift test was performed manually, and its grade was recorded. Then, with the knee flexed to 90 degrees, the examiner drew the projection of the foot in a neutral position and in maximum internal rotation, and the angle of internal rotation was measured from the axes built between the central point of the heel and the hallux. Results: In the ACL-deficient knee, it was observed that there is a statistically significant average internal rotation (IR) delta of 10.5 degrees between the groups when not adjusted for age, and 10.6 degrees when adjusted for age. Conclusions: Knees with ACL deficiency and with pivot shift test grade I do not show increased internal rotation in relation to knees with intact ACL. Knees with ACL deficiency and with pivot shift test grades II and III show increased internal rotation in comparison to healthy knees.

10.
OTA Int ; 7(2 Suppl): e304, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38487404

RESUMO

Orthopaedic surgeons routinely assess the biomechanical environment of a fracture to create a fixation construct that provides the appropriate amount of stability in efforts to optimize fracture healing. Emerging concepts and technologies including reverse dynamization, "smart plates" that measure construct strain, and FractSim software that models fracture strain represent recent developments in optimizing construct biomechanics to accelerate bone healing and minimize construct failure.

11.
Curr Diabetes Rev ; 20(9): e030124225214, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38178671

RESUMO

BACKGROUND: This study evaluated tibia's macroscopic structure, mechanical properties, and bone microarchitecture in rats with type 1 diabetes mellitus (T1DM). METHODS: Eighteen animals were divided into three groups (n=6): Non-diabetic (ND), diabetic (D), and diabetic+insulin (DI). T1DM was induced by streptozotocin; insulin was administered daily (4IU). The animals were euthanized 35 days after induction. The tibiae were removed and analyzed using macroscopic, micro-computed tomography (micro-CT) and three-point bending. The macroscopic analysis measured proximal-distal length (PD), antero-posterior thickness (AP) of proximal (AP-P) and distal (AP-D) epiphysis, and lateral-medial thickness (LM) of proximal (LM-P) and distal (LM-D) epiphysis. Micro-CT analysis closed porosity, tissue mineral density, and cortical thickness. The three-point bending test measured maximum strength, energy, and stiffness. RESULTS: The macroscopic analysis showed that D presented smaller measures of length and thickness (AP and AP-P) than ND and DI. More extensive measurements were observed of LM and AP-D thickness in DI than in D. In micro-CT, DI showed larger cortical thickness than D. Mechanical analysis showed lower strength in D than in other groups. CONCLUSIONS: T1DM reduces bone growth and mechanical strength. Insulin therapy in diabetic rats improved bone growth and fracture resistance, making diabetic bone similar to normoglycemic animals.


Assuntos
Densidade Óssea , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Hipoglicemiantes , Insulina , Tíbia , Microtomografia por Raio-X , Animais , Tíbia/diagnóstico por imagem , Tíbia/efeitos dos fármacos , Tíbia/patologia , Insulina/administração & dosagem , Insulina/uso terapêutico , Ratos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/fisiopatologia , Masculino , Densidade Óssea/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico , Ratos Wistar , Fenômenos Biomecânicos
12.
Med. U.P.B ; 43(1): 2-10, ene.-jun. 2024. ilus, tab
Artigo em Inglês | LILACS, COLNAL | ID: biblio-1531446

RESUMO

Objetivo: la mastectomía posterior al cáncer de seno produce diversas alteraciones posturales y biomecánicas en el plano frontal y sagital. Dichos cambios conducen a una cinemática alterada de la columna vertebral, desequilibrio muscular y alteración del soporte del peso del pie. Este estudio pretende describir las alteraciones de la baropodometría después de la mastectomía, con base en análisis baropodométricos de la presión media y la carga estática. Metodología: se realizó un estudio descriptivo correlacional. Las propiedades de carga del pie se identificaron en 17 mujeres mastectomizadas. Se utilizó una placa de presión Ecosanit Foot para medir la carga del pie en posición anatómica y con los pies juntos. Resultados: en el estudio participaron 17 mujeres mastectomizadas con una edad media de 54.16 años. Las pacientes reportaron una presión media significativamente mayor en la posición anatómica del lado dominante mastectomizado en comparación con el lado no dominante mastectomizado (227.2 ± 22.16 vs. 175.6 ± 14.95, p =0.05). No hubo diferencia significativa para la carga estática entre el lado dominante mastectomizado y el lado no dominante mastectomizado en la posición anatómica (52.43±4.069 vs. 49.69 ± 4.094, de forma respectiva). Conclusión: los resultados actuales de nuestro estudio evidenciaron la distribución desequilibrada del peso (vector carga en el pie) en pacientes después de la mastectomía. Por tanto, en este texto se describen las alteraciones posturales, musculares, y el desequilibrio estático y dinámico en pacientes con cáncer de seno.


Objective: mastectomy after breast cancer produces several postural and biomechanical alterations in the frontal and sagittal plane. Such changes lead to disturbed kinematics of the spine, muscle imbalance and altered foot weight bearing. This study aims to describe body balance alterations after mastectomy based on the baropodometric analysis of their mean pressure and static load. Methodology: a descriptive correlational research was carried out. Foot weight-bearing properties were identified in 17 patients who have undergone a mastectomy. An Ecosanit Foot pressure plate was used to measure foot load at anatomical position and keeping the feet together. Results: 17 female patients who had undergo mastectomy with a mean age of 54.16 years took part on the research. Patients who have had a dominant-side mastectomy demonstrated significant greater mean pressure at anatomical position when compared to those patients who have had a non-dominant side mastectomy (227.2 ± 22.16 versus 175.6 ± 14.95, p =0.05). There was no significant difference for static load between the patients who have had a dominant side mastectomy and patients who have had a non dominant side mastectomy at anatomical position (52.43 ± 4.069 versus 49.69 ± 4.094, respectively). Conclusion: the current results of our research showed the unbalanced weight distribution in patients after mastectomy. Consequently, it describes the postural and muscular alterations, and the static and dynamic imbalance in breast cancer patients.


Objetivo: A mastectomia após câncer de mama produz diversas alterações posturais e biomecânicas nos planos frontal e sagital. Tais mudanças levam a alteração da cinemática da coluna, desequilíbrio muscular e alteração do suporte de peso do pé. Este estudo tem como objetivo descrever as alterações baropodométricas após mastectomia, com base em análises baropodométricas de pressão média e carga estática. Metodologia: foi realizado estudo correlacional descritivo. Propriedades de carga nos pés foram identificadas em 17 mulheres mastectomizadas. Uma placa de pressão Ecosanit Foot foi usada para medir a carga do pé em posição anatômica e com os pés juntos. Resultados: participaram do estudo 17 mulheres mastectomizadas com idade média de 54,16 anos. Os pacientes relataram uma pressão média significativamente maior na posição anatômica do lado mastectomizado dominante em comparação ao lado mastectomizado não dominante (227,2 ± 22,16 vs. 175,6 ± 14,95, p =0,05). Não houve diferença significativa para a carga estática entre o lado mastectomizado dominante e o lado mastectomizado não dominante na posição anatômica (52,43 ± 4,069 vs. 49,69 ± 4,094, respectivamente). Conclusão: Os resultados atuais do nosso estudo mostraram distribuição de peso desequilibrada (carga vetorial no pé) em pacientes após mastectomia. Portanto, este texto descreve alterações posturais, musculares e desequilíbrio estático e dinâmico em pacientes com câncer de mama.


Assuntos
Humanos , Feminino
14.
Appl Physiol Nutr Metab ; 49(2): 213-222, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37820387

RESUMO

We have studied the effects of individual and combined treatment of insulin (I) and naringin (NAR) on the bone structure and biomechanical properties of femurs from streptozotocin (STZ)-induced diabetic rats. Male Wistar rats were divided into five groups: (1) controls, (2) STZ-induced diabetic rats, (3) STZ-induced diabetic rats treated with I, (4) STZ-induced diabetic rats treated with NAR, and (5) STZ-induced diabetic rats treated with I + NAR. Bone mineral density (BMD), bone histomorphometry, biomechanical testing, and bone biomarker expressions were accomplished in femur of all animals, as well as serum biochemical analyses. The combined treatment of I + NAR increased the body weight and the femur BMD from STZ-induced diabetic rats. The bone biomechanical properties and the bone morphology of the femurs from STZ-induced diabetic rats were also improved by the combined treatment. The increased number of osteoclasts in STZ-induced diabetic rats was partially prevented by I, NAR, or I + NAR. NAR or I + NAR completely blocked the decrease in the number of osteocalcin (+) cells in the femur from STZ-induced diabetic rats. RUNX family transcription factor 2 immunostaining was much lower in STZ-induced diabetic rats than in control animals; the combination of I + NAR totally blocked this effect. The combined treatment not only ameliorated bone quality and function, but also normalized the variables related to glucose metabolism. Therefore, the combination of I + NAR might be a better therapeutic strategy than the individual I or NAR administration to reduce bone complications in diabetic patients.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Flavanonas , Humanos , Ratos , Masculino , Animais , Diabetes Mellitus Tipo 1/complicações , Insulina , Ratos Wistar , Diabetes Mellitus Experimental/complicações , Densidade Óssea
15.
Artigo em Inglês | MEDLINE | ID: mdl-36625711

RESUMO

The purpose of this article was to describe a simple graphical driven method for determining the necessary two-vector mechanics (TVM) as an alternative solution to the ideal or single force. In orthodontics, some tooth movements are difficult to achieve, mainly because of the impossibility of getting the point of application for the necessary force system. Given two points in biomechanically accessible areas, adding together two vectors applied to those points will result in an equivalent force system. The method was developed based on previous research, 3,880 hypothetical cases were analyzed to determine the trends between the resulting forces and their relative locations. A graphical driven TVM method (GTVM) for establishing the necessary TVM is presented in a manner that combine different procedures from the traditional method that simplify the analysis and may allow the user to perform more complex orthodontic cases making easier to compare systems of force equivalents.


Assuntos
Fenômenos Mecânicos , Técnicas de Movimentação Dentária , Fenômenos Biomecânicos , Estresse Mecânico , Técnicas de Movimentação Dentária/métodos , Análise de Elementos Finitos
16.
Rev. Bras. Ortop. (Online) ; 59(1): 82-87, 2024. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1559601

RESUMO

Abstract Objective: Rupture of the anterior cruciate ligament (ACL) is one of the most common injuries in athletes and is often associated with damage to anterolateral structures. This combination of injuries presents itself clinically as a high-grade pivot shift test. The hypothesis of this study is that patients with ACL deficiency and high-grade pivot shift test should have an increased internal knee rotation. Methods: Twenty-two patients were tested. After effective spinal anesthesia, two tests were performed with the patient in supine position. First, the bilateral pivot shift test was performed manually, and its grade was recorded. Then, with the knee flexed to 90 degrees, the examiner drew the projection of the foot in a neutral position and in maximum internal rotation, and the angle of internal rotation was measured from the axes built between the central point of the heel and the hallux. Results: In the ACL-deficient knee, it was observed that there is a statistically significant average internal rotation (IR) delta of 10.5 degrees between the groups when not adjusted for age, and 10.6 degrees when adjusted for age. Conclusions: Knees with ACL deficiency and with pivot shift test grade I do not show increased internal rotation in relation to knees with intact ACL. Knees with ACL deficiency and with pivot shift test grades II and III show increased internal rotation in comparison to healthy knees.


Resumo Objetivo: A ruptura do ligamento cruzado anterior (LCA) é uma das lesões mais comuns em atletas e está frequentemente associada a danos nas estruturas anterolaterais. Esta combinação de lesões apresenta-se clinicamente como um teste de pivot shift de alto grau. A hipótese deste estudo é que pacientes com deficiência de LCA e teste de pivot shift de alto grau tenham aumento da rotação interna (RI) do joelho. Métodos: Vinte e dois pacientes foram testados. Após raquianestesia efetiva, foram realizados dois testes com o paciente em posição supina. Primeiro, o teste de pivot shift bilateral foi realizado manualmente e seu grau foi registrado. Em seguida, com o joelho flexionado a 90 graus, o examinador traçou a projeção do pé em posição neutra e em RI máxima e mediu o ângulo de RI a partir dos eixos construídos entre o ponto central do calcanhar e o hálux. Resultados: Joelhos com deficiência de LCA apresentam delta da RI média estatisticamente significativo de 10,5 graus entre os grupos sem ajuste de idade e de 10,6 graus com ajuste de idade. Conclusões: Joelhos com deficiência do LCA e teste de pivot shift de grau I não apresentam aumento da RI em relação aos joelhos com LCA íntegro. Joelhos com deficiência do LCA e teste de pivot shift de graus II e III apresentam RI em comparação aos joelhos saudáveis.


Assuntos
Humanos , Masculino , Feminino , Fenômenos Biomecânicos , Ligamento Cruzado Anterior/cirurgia , Instabilidade Articular
17.
Rev. Bras. Ortop. (Online) ; 59(1): 1-9, 2024. tab
Artigo em Inglês | LILACS | ID: biblio-1559613

RESUMO

Abstract Since its introduction by Ilizarov, the distraction osteogenesis technique has been used to treat trauma-related conditions, infections, bone tumors, and congenital diseases, either as methods of bone transport or elongation. One of the major dilemmas for the orthopedic surgeon who performs osteogenic distraction is establishing a reproducible method of assessing the progression of the osteogenesis, enabling the early detection of regenerate failures,inorder toeffectively interfereduring treatment, andtodeterminetheappropriate time to remove the external fixator. Several quantitative monitoring methods to evaluate the structural recovery and biomechanical properties of the bone regenerate at different stages,aswell as the bone healing process, are under study. These methods can reveal data on bone metabolism, stiffness, bone mineral content, and bone mineral density. The present review comprehensively summarizes the most recent techniques to assess bone healing during osteogenic distraction, including conventional radiography and pixel values in digital radiology, ultrasonography, bone densitometry and scintigraphy, quantitative computed tomography, biomechanical evaluation, biochemical markers, and mathematical models. We believe it is crucial to know the different methods currently available, and we understand that using several monitoring methods simultaneously can be an ideal solution, pointing to a future direction in the follow-up of osteogenic distraction.


Resumo Desde que foi descrita por Ilizarov, a técnica de osteogênese por distração tem sido utilizada para o tratamento de diversas condições relacionadas ao trauma, infecções, tumores ósseos edoenças congênitas, naforma detransporteou alongamento ósseo. Um dos dilemas mais comuns do cirurgião ortopédico que realiza distração osteogênica é o estabelecimentodeum método reprodutível deverificaçãoda progressão da osteogênese, que permita a detecção precoce de falhas no regenerado, para que se possa interferir de formaeficazduranteotratamento,bemcomodeterminarotempoapropriadoderemoção dofixadorexterno.Recentemente,váriosmétodosdemonitoramentoquantitativo,comos quais se poderia avaliar a recuperação da estrutura e as propriedades biomecânicas do regenerado ósseoemdiferentes estágios, alémdoprocessodecicatrização óssea, têm sido amplamente investigados. Por esses métodos, pode-se saber o conteúdo mineral ósseo, a densidade mineral óssea, a rigidez e o metabolismo ósseo. Nesta revisão, resumimos de forma abrangente as técnicas mais recentes para avaliar a cicatrização óssea durante a distração osteogênica, entre elas, métodos como aradiografia convencional e os valores de pixels em radiologia digital, a ultrassonografia, a densitometria e a cintilografia ósseas, a tomografia computadorizada quantitativa, a avaliação biomecânica, os marcadores bioquímicos e os modelos matemáticos. Consideramos fundamental o conhecimento dos diversos métodos à disposição atualmente e entendemos que a utilização de vários métodos de monitoramento simultaneamente possa ser uma solução ideal, que aponte para uma direção futura no seguimento da distração osteogênica.


Assuntos
Fenômenos Biomecânicos , Estudos de Avaliação como Assunto
18.
São Paulo med. j ; São Paulo med. j;142(2): e2022548, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1450518

RESUMO

ABSTRACT BACKGROUND: Current research supports the fact that prophylactic ankle taping (AT) is effective in preventing ankle injuries in amateur and elite sports athletes. OBJECTIVE: This study aimed to investigate the effect of AT on balance, knee valgus during drop jump and single-leg countermovement jump (SL-CMJ) landings, and ankle range of motion (ROM) restriction in healthy participants. DESIGN AND SETTING: A cross-sectional observational study was conducted at the Universidad Europea de Madrid, Madrid, Spain. METHODS: Participants: Thirty-nine healthy individuals participated in this study and performed the movements under two conditions (with and without tape). Outcome measurements: ankle ROM, balance, SL-CMJ height, flight time, ground time, and knee valgus. Before any intervention, a random process was developed with a 1:1 allocation ratio, and the participants were assigned to groups A (tape-no tape) and B (no tape-tape). RESULTS: Significant differences between tape and no-tape moments were observed for drop jump knee valgus flexion (P = 0.007), with an increase in knee valgus in participants with ankle taping. Similarly, the Y-balance testshowed a significant decrease in all variables (P = 0.001 and), ankle dorsiflexion (P = 0.001) in participants with ankle taping. CONCLUSIONS: AT is effective for immediate ankle ROM restriction. However, an increase in knee valgus during drop jump task and a decrease in lower limb balance were observed during drop jump task. Based on these results, it can be concluded that AT application in healthy individuals should not be recommended as it results in increase in injury risk factors.

19.
Rev. bras. med. esporte ; Rev. bras. med. esporte;30: e2021_0547, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1515070

RESUMO

ABSTRACT Introduction: The assessment of biomechanical changes related to the lower limbs is necessary in clinical practice to measure the potential risks of injury and the influences on existing dysfunction. Biomechanical changes related to previous ankle injuries are known to influence the performance of the entire lower limb. Objective: The aim of this study was to correlate muscle strength tests, performance tests and ankle stability with the Single Hop Test (SHT). Methods: 82 amateur runners were evaluated with isokinetic tests of quadriceps and hamstring muscle strength, as well as Y Balance Test (YBT), Weight-bearing Lung Test (WBLT), and the SHT. Results: The results showed there was a significant correlation between the SHT and the YBT in subjects with hamstring/quadriceps ratio (I/Q ratio) <0.55, and the length of the unilateral SHT with the peak torque of ipsilateral knee extensors. Conclusion: The study was successful in correlating the functional tests in question with the results obtained in isokinetic dynamometry. Level of Evidence V; Cross-Sectional Study.


RESUMEN Introducción: La evaluación de los cambios biomecánicos relacionados con las extremidades inferiores es necesaria en la práctica clínica para medir los riesgos potenciales de lesión y las influencias sobre la disfunción existente. Se sabe que los cambios biomecánicos relacionados con lesiones previas de tobillo influyen en el rendimiento de toda la extremidad inferior. Objetivo: Correlacionar las pruebas de fuerza muscular, las pruebas de rendimiento y la estabilidad del tobillo con la prueba de salto simple (Single Hop Test, SHT). Métodos: Se evaluó a 82 corredores aficionados con pruebas isocinéticas de fuerza muscular de cuádriceps e isquiotibiales, además de pruebas como Y Balance Test (YBT), Weight-bearing Lung Test (WBLT) y la prueba SHT. Resultados: Los resultados mostraron que existía una correlación significativa entre el SHT y el YBT en sujetos con ratio isquiotibiales/cuádriceps (ratio I/Q) <0,55, y la longitud del SHT unilateral con el par máximo de los extensores de la rodilla ipsilateral. Conclusión: El estudio logró correlacionar las pruebas funcionales en cuestión con los resultados obtenidos en la dinamometría isocinética. Nivel de Evidencia V; Estudio Transversal.


RESUMO Introdução: A avaliação de alterações biomecânicas relacionadas aos membros inferiores é necessária na prática clínica para mensurar os riscos potenciais de alguma lesão e as influencias sobre uma disfunção existente. As alterações biomecânicas relacionadas a lesões prévias de tornozelo são conhecidas pela influência na performance de todo o membro inferior. Objetivo: Correlacionar testes de força muscular, testes de performance e estabilidade do tornozelo com o teste de salto simples (Single Hop Test - SHT). Métodos: Foram avaliados 82 corredores amadores com testes isocinéticos de força muscular de quadríceps e isquiotibiais, além de testes Y Balance Test (YBT), Weight-bearing Lung Test (WBLT), e o SHT. Resultados: Os resultados demonstraram haver correlação significativa entre o SHT e o YBT nos indivíduos com relação Isquiotibiais/Quadríceps (relação I/Q) <0,55, e o comprimento do SHT unilateral com o pico de torque de extensores de joelho ipsilateral. Conclusão: O estudo foi bem sucedido em correlacionar os testes funcionais em questão com os resultados obtidos na dinamometria isocinética. Nível de Evidência V; Estudo Transversal.

20.
Rev. bras. med. esporte ; Rev. bras. med. esporte;30: e2022_0001, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1515073

RESUMO

ABSTRACT Introduction: Events such as the Paralympic Games leave a series of legacies in the host societies. This is also applicable to the development of associated scientific knowledge, particularly in the field of sports biomechanics. Objective: The objective of this study is to investigate the Brazilian scientific production in the field of biomechanics in Paralympic sports during the cycle that preceded and followed the Rio 2016 Paralympic Games. Additionally, the study aims to provide insights for future research endeavors. Methods: The search was conducted on the Lattes Platform, utilizing the filters "Assunto" and "Doutores" and the keywords "Paralímpico" and "Paralympic." In total, 723 authors were identified who published articles related to the topic. Subsequently, the curricula were accessed, and the articles were sorted and identified, resulting in 37 articles that met all inclusion criteria. Results: The results indicate that: a) Brazil witnessed an increase in the number of publications after London 2012; b) The majority of these productions (87%) originate from Public Institutions; c) There was a greater participation of other regions of Brazil in the production of knowledge in the area after Rio 2016; d) Individual modalities such as powerlifting and athletics were the most researched, despite Brazil's reference status in some collective modalities; e) Women remain a minority, both as participants in research and as authors of publications; f) The productions demonstrate high levels of quality; g) The most commonly used research techniques in biomechanics were kinematics and dynamometry. Conclusion: The field of biomechanics in Paralympic sports has significantly benefited from the legacy generated by the Rio 2016 Paralympics. As future challenges for researchers, the following aspects stand out: maintaining the quality of productions, expanding studies to include collective modalities, increasing the participation of other federated entities in the production of knowledge in this field, promoting greater gender equity, and incorporating new research techniques in biomechanics. Level of Evidence II; Review Study.


RESUMEN Introducción: Eventos como los Juegos Paralímpicos dejan una serie de legados en las sociedades anfitrionas. Esto también es aplicable al desarrollo de conocimiento científico asociado, especialmente en el campo de la biomecánica deportiva. Objetivo: El objetivo de este estudio es investigar la producción científica brasileña en el campo de la biomecánica en deportes paralímpicos durante el ciclo que precedió y siguió a los Juegos Paralímpicos de Río 2016. Además, el estudio tiene como propósito brindar ideas para futuros esfuerzos de investigación. Métodos: La búsqueda se realizó en la Plataforma Lattes, utilizando los filtros " Assunto " y "Doutores" y las palabras clave "Paralímpico" y "Paralympic". En total, se identificaron 723 autores que publicaron artículos relacionados con el tema. Posteriormente, se accedió a los currículos y se clasificaron e identificaron los artículos, lo que resultó en 37 artículos que cumplieron con todos los criterios de inclusión. Resultados: Los resultados indican que: a) Brasil experimentó un aumento en el número de publicaciones después de Londres 2012; b) La mayoría de estas producciones (87%) provienen de Instituciones Públicas; c) Después de Río 2016, hubo una mayor participación de otras regiones de Brasil en la producción de conocimiento en el área; d) Las modalidades individuales, como levantamiento de pesas y atletismo, fueron las más investigadas, a pesar del estatus de referencia de Brasil en algunas modalidades colectivas; e) Las mujeres siguen siendo una minoría, tanto como participantes en investigaciones como autoras de publicaciones; f) Las producciones demuestran altos niveles de calidad; g) Las técnicas de investigación más utilizadas en biomecánica fueron la cinemática y la dinamometría. Conclusión: El campo de la biomecánica en deportes paralímpicos ha sido significativamente beneficiado por el legado generado por los Juegos Paralímpicos de Río 2016. Como desafíos futuros para los investigadores, se destacan los siguientes aspectos: mantener la calidad de las producciones, ampliar los estudios para incluir modalidades colectivas, aumentar la participación de otras entidades federadas en la producción del conocimiento en este campo, promover una mayor equidad de género e incorporar nuevas técnicas de investigación en biomecánica. Nivel de Evidencia II; Estudio de Revisión.


RESUMO Introdução: Eventos como os Jogos Paralímpicos deixam uma série de legados nas sociedades que as sediam. Não seria diferente quando se trata do desenvolvimento do conhecimento científico associado, em especial a biomecânica do esporte. Objetivo: Investigar a produção científica brasileira produzida em biomecânica no esporte paralímpico no ciclo que antecedeu e sucedeu os Jogos Paralímpicos Rio 2016, além de fornecer insights para novos estudos. Métodos: Foram realizadas buscas na Plataforma Lattes, sendo habilitados os filtros "Assunto" e "Doutores", com as palavras-chave "Paralímpico" e "Paralympic". Ao todo, foram encontrados 723 autores que publicaram artigo(s) relacionado(s) com o tema. Após acessar os currículos, os artigos foram triados e identificados, resultando em 37 artigos que preencheram todos os critérios de inclusão. Resultados: Os resultados mostram que a) Após Londres-2012, o Brasil tem aumentado o número de publicações; b) Grande parte das produções (87%) são oriundas de Instituições Públicas, c) Após Rio-2016 houve uma maior participação de outras regiões do Brasil na produção do conhecimento na área, d) Apesar do Brasil ser referência em algumas modalidades coletivas, modalidades individuais como o powerlifting e o atletismo, são as mais pesquisadas, e) Mulheres ainda são minoria, tanto como participantes das pesquisas quanto na autoria das publicações, f) As produções atingem elevados extratos de qualidade, g) As técnicas de pesquisa em biomecânica mais utilizadas foram a cinemática e dinamometria. Conclusão: A biomecânica no esporte paralímpico tem se valido do legado gerado pelas paralimpíadas Rio-2016. Como desafios futuros para os pesquisadores, destacam-se: manutenção da qualidade das produções, ampliação dos estudos para as modalidades coletivas, aumento da participação de outros entes federados na produção do conhecimento na área, promoção de uma maior equidade de gênero e incorporação de novas técnicas de pesquisa em biomecânica. Nível de Evidência II; Estudo de Revisão.

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