The key research of sports in maintaining human health / A pesquisa chave do esporte na manutenção da saúde humana / La investigación clave del deporte para mantener la salud humana

ABSTRACT Introduction One of the evaluation factors of human health is bone health, and an evaluation index of bone health is osteoporosis. Sports are an effective way to improve the human body. Objective The paper discusses the effects of different exercise intensities on human bone health. Methods The thesis selected 51 female college students, designed different exercise intensities of fitness running intervention programs, and conducted a 12-month exercise intervention. We divide female college students into three groups. The subjects' bone mineral density (BMD), serum alkaline phosphatase (ALP), and serum osteocalcin (BGP) were tested before and after the experiment. Results The differences in femoral BMD, serum ALP, serum BGP, and lumbar spine BMD of the three groups of volunteers were significant (P<0.05), while the differences in ulna and radius BMD were not significant. Conclusions Sports can promote human bone health. At the same time, the effect of fitness running on human BMD is site-specific. Level of evidence II; Therapeutic studies - investigation of treatment results.

RESUMO Introdução Um dos fatores de avaliação da saúde humana é a saúde óssea, e um índice de avaliação da saúde óssea é a osteoporose. Os esportes são uma forma eficaz de melhorar o corpo humano. Objetivo o artigo discute os efeitos de diferentes intensidades de exercício na saúde óssea humana. Métodos A tese selecionou 51 universitárias, elaborou diferentes intensidades de exercícios em programas de intervenção de corrida de aptidão e conduziu uma intervenção de exercícios de 12 meses. Dividimos as universitárias em três grupos. A densidade mineral óssea (BMD), fosfatase alcalina sérica (ALP) e osteocalcina sérica (BGP) dos indivíduos foram testadas antes e depois do experimento. Resultados As diferenças na DMO femoral, ALP sérica, BGP sérica e DMO da coluna lombar dos três grupos de voluntários foram significativas (P <0,05), enquanto as diferenças na DMO da ulna e rádio não foram significativas. Conclusão O esporte pode promover a saúde óssea humana. Ao mesmo tempo, o efeito da corrida adaptativa na DMO humana é específico do local. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción Uno de los factores de evaluación de la salud humana es la salud ósea y un índice de evaluación de la salud ósea es la osteoporosis. Los deportes son una forma eficaz de mejorar el cuerpo humano. Objetivo El artículo analiza los efectos de diferentes intensidades de ejercicio en la salud ósea humana. Métodos La tesis seleccionó a 51 estudiantes universitarias, diseñó diferentes intensidades de ejercicio de programas de intervención para correr y realizó una intervención de ejercicio de 12 meses. Dividimos a las estudiantes universitarias en tres grupos. La densidad mineral ósea (DMO), la fosfatasa alcalina sérica (ALP) y la osteocalcina sérica (BGP) de los sujetos se analizaron antes y después del experimento. Resultados Las diferencias en la DMO femoral, la ALP sérica, la BGP sérica y la DMO de la columna lumbar de los tres grupos de voluntarios fueron significativas (P <0,05), mientras que las diferencias en la DMO del cúbito y del radio no fueron significativas. Conclusión Los deportes pueden promover la salud ósea humana. Al mismo tiempo, el efecto de la actividad física en la DMO humana es específico del sitio. Nivel de evidencia II; Estudios terapéuticos: investigación de los resultados del tratamiento.

El peroné: mal alumno, pero buen profesor. (¿Qué tiene prioridad biológica: la integridad, o la supervivencia?) / Fibula: a bad pupil but a good profesor. (What comes first, integrity or survival?)

La concepción original del mecanostato como un regulador de la rigidez estructural ósea orientado a mantener un determinado 'factor de seguridad' en todos los esqueletos parece no corresponder por igual a cualquier hueso y para cualquier tipo de estímulo. Hemos descubierto que la estructura cortical diafisaria del peroné humano manifiesta un comportamiento ambiguo del sistema, referido al uso del pie. La diáfisis peronea, además de ser insensible al desuso, se rigidiza, como sería de esperar, por entrenamientos en disciplinas deportivas que rotan o revierten el pie (hockey, fútbol, rugby); pero, llamativamente, se flexibiliza en su mitad proximal por entrenamiento en carrera larga, que optimiza el rendimiento del salto que acompaña a cada paso. La referida rigidización robustecería la región peronea de inserción de los músculos que rotan o revierten el pie, favoreciendo la locomoción sobre terrenos irregulares o 'gambeteando', propia de especies predadoras como los leopardos. La 'inesperada' flexibilización proximal, pese a reducir la resistencia a la fractura por flexión lateral (poco frecuente en el hombre), favorecería la absorción elástica de la energía contráctil de la musculatura inserta, optimizando el rendimiento del salto al correr, condición vital para especies presas como las gacelas. La falta de analogía de estas respuestas de la estructura peronea a distintos entrenamientos, incompatible con el mantenimiento de un factor de seguridad, sugiere su vinculación preferencial con la optimización de aptitudes esqueléticas con valor selectivo. Esto ampliaría el espectro regulatorio del mecanostato a propiedades esqueléticas 'vitales', más allá del control de la integridad ósea. Su manifestación en el hombre, ajena a connotaciones selectivas (quizá resultante del mantenimiento de genes ancestrales), permitiría proponer la indicación de ejercicios orientados en direcciones preferenciales a este respecto, especialmente cuando estas coincidieran con las de las fuerzas que podrían fracturar al hueso. (AU)

The original notion of the mechanostat as a regulator of bone structural rigidity oriented to maintain a certain 'safety factor' in all skeletons does not seem to correspond equally to every bone and for any type of stimulus. We have discovered that the diaphyseal cortical structure of the human fibula shows an ambiguous behavior of the system, with reference to the use of the foot. The peroneal shaft, in addition to being insensitive to disuse, becomes stiffened, as might be expected, by training in sport disciplines that involve rotating or reversing the foot (hockey, soccer, rugby); but, remarkably, it becomes more flexible in its proximal half by long-distance running training, which optimizes the performance of the jump that accompanies each step. The stiffening would strengthen the peroneal region of insertion of the muscles that rotate or reverse the foot, favoring locomotion on uneven terrain or 'dribbling', typical of predatory species such as leopards. The 'unexpected' proximal flexibilization, despite reducing the resistance to lateral flexion fracture (rare in human), would favor the elastic absorption of contractile energy from the inserted muscles, optimizing jumping performance when running, a vital condition for prey species such as gazelles. The lack of analogy of these responses of the peroneal structure to different training, incompatible with the maintenance of a safety factor, suggests its preferential link with the optimization of skeletal aptitudes with selective value. This would expand the regulatory spectrum of the mechanostat to 'vital' skeletal properties, beyond the control of bone integrity. Its manifestation in humans, oblivious to selective connotations (perhaps resulting from the maintenance of ancestral genes), would make it possible to propose the indication of exercises oriented in preferential directions, especially when they coincide with the direction of the forces that could fracture the bone. (AU)

¿A qué pregunta responde "el hueso"?: una cuestión de direccionalidad estructural y organización biológica (hueso y huesos, del big-bang a la osteoporosis) / To which question is 'bone' the answer?: a matter of structural directionality and biological organization (bone and bones, from the big bang to osteoporosis)

La "razón de ser" de nuestros huesos y esqueletos constituye un dilema centralizado en los conceptos biológicos de "estructura" y "organización", cuya solución necesitamos comprender para interpretar, diagnosticar, tratar y monitorear correctamente las osteopatías fragilizantes. Últimamente se ha reunido conocimiento suficiente para proponer aproximaciones razonables a ese objetivo. La que exponemos aquí requiere la aplicación de no menos de 6 criterios congruentes: 1) Un criterio cosmológico, que propone un origen común para todas las cosas; 2) Un criterio biológico, que explica el origen común de todos los huesos; 3) Un enfoque epistemológico, que desafía nuestra capacidad de comprensión del concepto concreto de estructura y del concepto abstracto de organización, focalizada en la noción rectora de direccionalidad espacial; 4) Una visión ecológica, que destaca la importancia del entorno mecánico de cada organismo para la adecuación de la calidad mecánica de sus huesos a las "funciones de sostén" que les adjudicamos; 5) Una correlación entre todo ese conocimiento y el necesario para optimizar nuestra aptitud para resolver los problemas clínicos implicados y 6) Una jerarquización del papel celular en el manejo de las interacciones genético-ambientales necesario para asimilar todo el problema a una simple cuestión de organización direccional de la estructura de cada hueso. Solo aplicando estos 6 criterios estaríamos en condiciones de responder a la incógnita planteada por el título. La conclusión de esta interpretación de la conducta y función de los huesos debería afectar el fundamento de la mayoría de las indicaciones farmacológicas destinadas al tratamiento de la fragilidad ósea. (AU)

The nature of the general behavior of our bones as weight-bearing structures is a matter of two biological concepts, namely, structure and organization, which are relevant to properly interpret, diagnose, treat, and monitor all boneweakening diseases. Different approaches can be proposed to trace the corresponding relationships. The one we present here involves six congruent criteria, namely, 1) a cosmological proposal of a common origin for everything; 2) a biological acknowledgement of a common origin for all bones; 3) the epistemological questioning of our understanding of the concrete concept of structure and the abstract notion of organization, focused on the lead idea of directionality; 4) the ecological insight that emphasizes the relevance of the mechanical environment of every organism to the naturally-selected adjustment of the mechanical properties of their mobile bones to act as struts or levers; 5) The clinical aspects of all the alluded associations; 6) The central role of bone cells to control the genetics/ environment interactions of any individual as needed to optimize the directionality of the structure of each of his/her bones to keep their mechanical ability within physiological limits. From our point of view, we could only solve the riddle posed by the title by addressing all of these six criteria. The striking conclusion of our analysis suggests that the structure (not the mass) of every bone would be controlled not only to take care of its mechanical ability, but also to cope with other properties which show a higher priority concerning natural selection. The matter would be that this interpretation of bone behavior and 'function' should affect the rationales for most pharmacological indications currently made to take care of bone fragility. (AU)

Neuromuscular fitness in early life and its impact on bone health in adulthood: a systematic review / Aptidão neuromuscular na juventude e o impacto na saúde óssea na idade adulta: uma revisão sistemática

ABSTRACT Objective: To systematically review the literature to verify the relationship between neuromuscular fitness indicators in childhood/adolescence and bone strength variables in adulthood. Data sources: A systematic review was conducted in PUBMED, SCOPUS, SPORTDiscus, Web of Science, PsycINFO, LILACS, and SciELO, covering the entire period until March 2019. Data synthesis: The search identified 1149 studies. After duplicity analysis and eligibility criteria, four studies were reported. In one study, baseline was childhood and, in the others, adolescence. In childhood, when adjusting the model for age and body mass index, a statistically significant relation was found for girls: standing long jump with quantitative ultrasound index (β=0.11; p<0.05) and with speed of sound (β=0.14; p<0.01). However, when controlling muscular performance in adulthood, the relationship was no longer significant. In adolescence, coefficients ranged from 0.16 for neuromotor battery and bone mineral density (BMD) in the lumbar region to 0.38 for hanging leg lift test and BMD of arms. The explained variance varied between 2% (bent arm hang for BMD total) and 12% (hanging leg-lift for BMD arms), therefore, a higher performance in neuromuscular fitness in adolescence was associated with better bone strength in adulthood. Conclusions: In adults, bone strength variables showed significant correlation from low to moderate magnitude with neuromuscular fitness indicators in adolescence, but not in childhood, after controlling for adult performance in neuromuscular fitness. However, there is limited evidence to support the neuromuscular fitness in early life as a determinant of bone strength in adulthood.

RESUMO Objetivo: Revisar sistematicamente a literatura para verificar a relação entre indicadores da aptidão neuromuscular na infância/adolescência e variáveis de resistência óssea na idade adulta. Fonte de dados: Revisão sistemática com pesquisa de artigos conduzida no PUBMED, SCOPUS, SPORTDiscus, Web of Science, PsycINFO, LILACS and SciELO, abrangendo todo o período da base até março de 2019. Síntese dos dados: A busca identificou 1.149 estudos, após análise de duplicidade e dos critérios de elegibilidade, quatro estudos foram relatados. Em um dos estudos, o baseline foi a infância e, nos demais, a adolescência. Na infância, ao ajustar o modelo por idade e índice de massa corporal, foi encontrada relação estatisticamente significativa para as meninas: salto em distância com índice quantitativo de ultrassom (β=0,11; p<0,05) e com velocidade do som (β=0,14; p<0,01). Entretanto, ao se fazer o controle do desempenho muscular na idade adulta, a relação deixou de ser significativa. Na adolescência, coeficientes variaram de 0,16 para bateria neuromotora e densidade mineral óssea (DMO) lombar a 0,38 para o teste de elevação de pernas em suspensão e a DMO dos braços. Variação explicada entre 2% (suspensão na barra e DMO do corpo total) e 12% (elevação de pernas em suspensão e DMO dos braços), portanto, melhor desempenho na aptidão neuromuscular na adolescência, mais resistência óssea na idade adulta. Conclusões: Em adultos, variáveis de resistência óssea apresentaram correlação significativa em magnitude baixa a moderada com indicadores da aptidão neuromuscular na adolescência, mas não na infância, após controlar pelo desempenho adulto na aptidão neuromuscular. No entanto, existe evidência limitada para apoiar a aptidão neuromuscular na juventude como fator determinante da resistência óssea na fase adulta.

Proposal for a new histological scoring system for cartilage repair

OBJECTIVE: This study aimed to develop a new histological scoring system for use in a partial-thickness cartilage repair animal model. Although previous papers have investigated the regeneration of articular cartilage, the good results achieved in small animals have not been replicated in large animal models or humans, possibly because of the frequent use of models with perforation of the subchondral bone plates. Partial-thickness lesions spare the subchondral bone, and this pattern is the most frequent in humans; therefore, new therapies should be tested using this model. However, no specific histological score exists to evaluate partial-thickness model results. METHODS: Histological sections from 30 ovine knees were reviewed to develop a new scoring system. The sections were subjected to H&E, Safranin O, and Masson's trichrome staining. RESULTS: This paper describes a new scoring tool that is divided into sections in detail: repair of tissue inside the lesion, cartilage around the lesion and degenerative changes at the base of the lesion. Scores range from 0 to 21; a higher score indicates better cartilage repair. DISCUSSION: Unlike existing tools, this new scale does not assign points for the positioning of a tidemark; we propose evaluation of the degenerative changes to the subchondral bone and calcified cartilage layer. It is necessary to remove the whole joint to access and study the evolution of the lesion as well as the surrounding tissue. CONCLUSION: This article emphasizes the importance of a partial-thickness animal model of cartilage repair and presents a new histological scoring system.

Somatic maturation and the relationship between bone mineral variables and types of sports among adolescents: cross-sectional study / Maturação somática e o relacionamento entre variáveis minerais ósseas e modalidades esportivas em adolescentes: estudo transversal

ABSTRACT CONTEXT AND OBJECTIVE: Peak height velocity (PHV) is an important maturational event during adolescence that affects skeleton size. The objective here was to compare bone variables in adolescents who practiced different types of sports, and to identify whether differences in bone variables attributed to sports practice were dependent on somatic maturation status. DESIGN AND SETTING: Cross-sectional study, São Paulo State University (UNESP). METHODS: The study was composed of 93 adolescents (12 to 16.5 years old), divided into three groups: no-sport group (n = 42), soccer/basketball group (n = 26) and swimming group (n = 25). Bone mineral density and content were measured using dual-energy x-ray absorptiometry and somatic maturation was estimated through using peak height velocity. Data on training load were provided by the coaches. RESULTS: Adolescents whose PHV occurred at an older age presented higher bone mineral density in their upper limbs (P = 0.018). After adjustments for confounders, such as somatic maturation, the swimmers presented lower values for bone mineral density in their lower limbs, spine and whole body. Only the bone mineral density in the upper limbs was similar between the groups. There was a negative relationship between whole-body bone mineral content and the weekly training hours (β: -1563.967; 95% confidence interval, CI: -2916.484 to -211.450). CONCLUSION: The differences in bone variables attributed to sport practice occurred independently of maturation, while high training load in situations of hypogravity seemed to be related to lower bone mass in swimmers.

RESUMO CONTEXTO E OBJETIVO: O pico de velocidade de crescimento (PVC) constitui importante evento maturacional durante a adolescência, afetando o tamanho do esqueleto. O objetivo do estudo foi comparar variáveis ósseas em adolescentes praticantes de diferentes modalidades esportivas, bem como identificar se diferenças nas variáveis ósseas atribuídas à prática esportiva são dependentes do estado da maturação somática. DESENHO E LOCAL: Estudo transversal, Universidade Estadual Paulista (UNESP). MÉTODOS: O estudo foi constituído por 93 adolescentes (12 a 16,5 anos), divididos em três grupos: grupo sem envolvimento esportivo (n = 42), futebol/basquete (n = 26) e natação (n = 25). A densidade e conteúdo mineral ósseo foram mensurados utilizando absortiometria de raio-x de dupla energia e a maturação somática foi estimada através do uso do PVC. Informações sobre volume de treinamento foram fornecidas pelos treinadores. RESULTADOS: Adolescentes com idade tardia no PVC apresentaram maiores valores de densidade mineral óssea em membros superiores (P = 0,018). Após ajustes por variáveis de confusão, como a maturação somática, os nadadores apresentaram menores valores de densidade mineral óssea em membros inferiores, coluna e corpo inteiro. Apenas a densidade mineral óssea de membros superiores foi similar entre os grupos. Existiu relação negativa entre conteúdo mineral ósseo de corpo inteiro e tempo de treino semanal (β: -1563.967; 95% intervalo de confiança, IC: -2916.484 a -211.450). CONCLUSÃO: As diferenças em variáveis ósseas atribuídas à prática esportiva ocorrem independentemente da maturação, enquanto elevada quantidade de treinamento em situações de hipogravidade parece estar relacionada com menor massa óssea em nadadores.

Enfermedad de paget ósea: breve revisión de la literatura a propósito de un caso / Paget ́s bone disease: case report and brief literature review

La osteítis deformante o enfermedad de Paget es un trastorno óseo, crónico, poco frecuente en Chile, que puede afectar típicamente a pacientes después de los 55 años. Su etiología es probablemente multifactorial: actualmente se considera como posiblemente implicados factores ambientales y genéticos.La mayor parte de los pacientes son asintomáticos. Los diagnósticos habitualmente se realizan en base a hallazgos radiológicos. Cuando existen síntomas, suelen ser dolor y/o deformidad ósea. Pueden comprometerse uno o varios huesos.Ante su sospecha clínica, la exploración diagnóstica requiere de al menos el estudio con radiografías simples de las lesiones sospechosas, cintigrama óseo y parámetros de actividad metabólica ósea; recomendándose los niveles séricos de fosfatasas alca-linas, por su bajo costo y elevada disponibilidad.Las metástasis óseas condensantes son un importante diagnóstico diferencial a con-siderar.Sobre el tratamiento, se recomienda el uso de fármacos antirresortivos como terapia específica, y el uso de ortesis y terapia física.El seguimiento es clínico y con biomarcadores de recambio óseo.

Osteitis-deformans or Paget's disease is a chronic bone disorder uncommon in Chile, with a typical presentation after age 55. Its etiology is probably multifactorial: It is actualy considered that environmental and genetic factors are mainly involved.Most patients are asymptomatic. Diagnoses are usualy performed based on radio-logical findings. When symptoms exist, they are pain and/or bone deformity. One or several bones can be affects.If it ́s suspect, the diagnostic exploration requires at least the study with x-rays of the suspicious lesions, bone scintigraphy and parameters of bone metabolic activity, being recommended the serum levels of alkaline phosphatases, for its low cost and high availability.Condensing bone metatases have to be considered like an important differential di-agnosis.For the treatment, the use of antiresorptive drugs as specific therapy is recommend-ed, and the use of orthotics and physical therapy.Follow-up is made with clinical findings and with biomarkers of bone turnover.

Utilização de plasma rico em plaquetas de coelhos com poucos leucócitos e hemácias para a consolidação de ossos / Use of plasma rich in platelets of rabbits with few leukocytes and erythrocytes to consolidate bones

Objetivou-se utilizar o plasma rico em plaquetas, obtido por técnica capaz de produzir um produto autólogo, com reduzido número de leucócitos e hemácias, e avaliar, por meio de radiografias, a capacidade de cicatrização de uma falha óssea induzida no rádio de coelhos. Foram coletados 10,5mL de sangue por via intracardíaca, o qual foi distribuído em três tubos de hemossedimentação contendo citrato de sódio. Os tubos contendo as amostras foram submetidos a uma centrifugação a 2.000rpm (670,8G) por 20 minutos, e da coluna de sedimentação foram aspirados de cada tubo 1.000µL de plasma para a redução do volume sobrenadante. Aspirou-se o plasma acima do anel de leucócitos e transferiu-se para outro tubo para centrifugação a 2.000rpm por 10 minutos. O conteúdo plaquetário no fundo do tubo foi ressuspendido e homogeneizado a 1.000µL do plasma sobrenadante para formar o PRP líquido. Uma falha de 1,0cm foi realizada no rádio esquerdo de cada coelho. O tempo de consolidação foi observado por meio de exame radiográfico aos 45 e 90 dias de pós-operatório (PO). As imagens foram comparadas entre o grupo controle (G1) e o grupo que recebeu o implante de PRP por via transdérmica (G2). A evolução da cicatrização foi verificada com auxílio do programa Adobe Photoshop CC e em uma escala de cinza que representa o contraste. No G2 foi verificada média de 63% de contraste aos 45 dias de PO e de 65% aos 90 dias de PO. No G2, aos 45 dias de PO, a média encontrada foi de 42,7%, e aos 90 dias de PO, 31,25%, indicando que houve evolução do processo de reparação óssea em comparação ao grupo que não recebeu o implante de PRP. O método de obtenção de plasma rico em plaqueta autólogo de coelhos reduziu o número de leucócitos e hemácias e recuperou o número de plaquetas, sendo este maior ou igual aos valores fisiológicos para a espécie. O PRP obtido foi capaz de acelerar o processo de consolidação óssea em coelhos.

The aim of this study was to use the platelet-rich plasma obtained by a technique capable of producing an autologous product, with a reduced number of white blood cells and red blood cells and assessed by radiographs, the healing ability of a bone defect induced in the radio rabbits. 10.5mL of blood was collected via intracardiac blood sedimentation and distributed into three tubes containing sodium citrate. The tubes containing the samples were subjected to centrifugation at 2,000 rpm (670.8G) for 20 minutes and the sediment column were aspirated from each plasma tube1,000μL to reduce the supernatant volume. The plasma was aspirated from above the leukocytes ring and transferred to another tube for centrifugation at 2,000 rpm for 10 minutes. The platelet content in the tube bottom was resuspended and homogenized to 1,000μL plasma supernatant PRP to form the liquid. A1.0 cm failure was performed on the left radio of each rabbit. The healing time was observed by means of radiographic examination at 45 and 90 days after surgery. The images were compared between the control group (G1) and the group receiving PRP implant transdermally (G2). The healing progress was assessed with the help of Adobe Photoshop program and a gray scale that represents the contrast. G2 had an average of 63% contrast at 45 days PO and 65% at 90 days PO. In G2, at 45 days PO the average was 42.7% and at 90 days PO 31.25% indicating that there was an increase in bone repair process compared to the group that did not receive the PRP implant. The method of obtaining an autologous platelet rich plasma of rabbits reduced the number of leukocytes and erythrocytes and platelets recovered which is greater than or equal to the physiological range for the species. The obtained PRP was able to accelerate the process of bone healing in rabbits.

Efecto de la yerba mate (ilex paraguariensis) sobre el hueso de ratas ovariectomizadas / Effect of yerba mate (ilex paraguariensis) on bone in ovariectomized rats

El consumo de yerba mate (Ilex paraguariensis) es habitual en la Argentina y otros países de América del Sur. La yerba mate, al igual que el café y el té, contiene xantinas y polifenoles. El consumo de café ha mostrado tener impacto negativo sobre la densidad mineral ósea (DMO), mientras que el té ha mostrado tener efecto protector. En mujeres posmenopáusicas tomadoras de mate se halló mayor DMO de columna lumbar y cuello femoral en comparación con controles que no bebían mate. La DMO también fue mayor en ratas que recibieron una infusión de yerba mate y dieta baja en calcio; sin embargo, este incremento no fue capaz de revertir el efecto negativo del bajo contenido de calcio sobre las propiedades biomecánicas y la conectividad trabecular. El objetivo de este trabajo fue estudiar el tejido óseo de ratas ovariectomizadas (OVX) luego de recibir una infusión de yerba mate por 90 días en reemplazo del agua de bebida. Se utilizaron ratas Sprague Dawley (n=16) hembras divididas en 2 grupos: OVX+agua y OVX+yerba. Otro grupo de ratas (n=6) fue sometido a una cirugía simulada (Sham). El estudio mostró claramente el efecto deletéreo de la ovariectomía sobre todos los parámetros estudiados (DMO, histomorfometría ósea, conectividad trabecular y biomecánica) respecto del grupo Sham. El grupo OVX+yerba no mostró diferencias con el grupo OVX+agua en ninguno de los parámetros analizados, por lo que la yerba mate no produciría efecto alguno sobre el hueso de ratas adultas ovariectomizadas. (AU)

Yerba mate (Ilex paraguariensis) consumption is common in Argentina and other South American countries. Like coffee and tea, yerba mate contains xanthines and polyphenols. It has been reported that caffeine consumption has a negative impact on bone mineral density (BMD) while tea has been shown to have a protective effect. On the other hand, in postmenopausal women that usually consumed yerba mate, lumbar spine and femoral neck BMDs were higher than in non-consumers. BMD was also higher in rats that received a yerba mate infusion and low calcium diet. However, this increase was not sufficient to reverse the negative effect of a low calcium diet on bone biomechanical properties and trabecular connectivity. The aim of this work was to study bone tissue in ovariectomized (OVX) rats receiving an infusion of yerba mate instead of drinking water for 90 days. Female Sprague Dawley rats (n=16) were divided into 2 groups: OVX+water and OVX+yerba. A third group of rats (n=6) was submitted to sham surgery (Sham). Results clearly showed the deleterious effect of ovariectomy on all studied parameters (BMD, bone histomorphometry, trabecular connectivity and biomechanical properties) compared to Sham group. The OVX+yerba group showed no difference with OVX+water group in all analyzed parameters. It is concluded that yerba mate does not produce any effect on the bone of ovariectomized adult rats. (AU)

Biomecánica de las fracturas por stress / Biomechanical features of stress fractures

Se define como estrés (stress) tanto la fuerza que una carga externa ejerce sobre un cuerpo sólido como la fuerza reactiva que acompaña a la primera (Ley de Newton), por unidad de área imaginaria transversal a su dirección. Las cargas internas reactivas inducen deformaciones proporcionales del cuerpo. La resistencia del cuerpo a deformarse se llama rigidez. La deformación puede resquebrajar el cuerpo y, eventualmente, producir una fractura por confluencia de trazos. La resistencia del cuerpo a separarse en fragmentos por esa causa se llama tenacidad. La resistencia del cuerpo a la fractura es proporcional al stress que puede soportar sin separarse en fragmentos por deformación (no hay fractura sin deformación y sin stress previo). El stress máximo que un cuerpo puede soportar sin fracturarse resulta de una combinación de ambas propiedades: rigidez y tenacidad, cada una con distintos determinantes biológicos. Una o varias deformaciones del cuerpo pueden provocarle resquebrajaduras sin fracturarlo. La acumulación de resquebrajaduras determina la "fatiga" del material constitutivo del cuerpo, que reduce su rigidez, tenacidad y resistencia a la fractura para la próxima ocasión ("fragilidad por fatiga"). En el caso de los huesos, en general, los términos stress y fatiga tienen las connotaciones amplias referidas, respecto de todas las fracturas posibles. La fatiga predispone a fracturas a cargas bajas, que se denominan (correctamente) "fracturas por fatiga" y también (incorrectamente) "fracturas por stress", para distinguirlas de las que ocurren corrientemente, sin resquebrajaduras previas al trauma, que se denominan (incorrectamente) "fracturas por fragilidad, o por insuficiencia". En realidad, todas las fracturas se producen por stress y por fragilidad o insuficiencia (en conjunto); pero la distinción grosera entre fracturas "por fatiga, o por stress", por un lado, y "por fragilidad" o "por insuficiencia", por otro, aceptando las amplias connotaciones referidas antes, tiene valor en la práctica clínica. Este artículo intenta explicar esas particularidades biomecánicas y describir las distintas condiciones que predisponen a las fracturas "por fatiga o por stress" en la clínica, distinguiéndolas de las fracturas "por fragilidad o por insuficiencia" (manteniendo estas denominaciones) y detallando las características de interés directo para su diagnóstico y tratamiento. (AU)

The term "stress" expresses the force exerted by an external load on a solid body and the accompanying, opposed force (Newton's Law), expressed per unit of an imaginary area perpendicular to the loading direction. The internal loads generated this way deform (strain) proportionally the body's structure. The resistance of the body to strain expresses its stiffness. Critical strain magnitudes may induce micro-fractures (microdamage), the confluence of which may fracture the body. The body's resistance to separation into fragments determines its toughness. Hence, the body's resistance to fracture is proportional to the stress the body can support (or give back) while it is not fractured by the loadinduced strain (no stress, no strain -> no fracture). Therefore, the maximal stress the body can stand prior to fracture is determined by a combination of both, its stiffness and its toughness; and each of those properties is differently determined biologically. One or more deformations of the body may induce some microdamage but not a fracture. Microdamage accumulation determines the fatigue of the material constitutive of the body and reduces body's toughness, leading to a "fatigue-induced fragility". In case of bones, in general, both stress and fatigue have the referred, wide connotations, regarding any kind of fractures. In particular, bone fatigue predisposes to low-stress fractures, which are named (correctly) "fatigue fractures" and also misnamed "stress fractures", to distinguish them from the current fractures that occur without any excess of microdamage, that are named (wrongly) "fragility" or "insufficiency" fractures. In fact, all fractures result from all stress and fragility or insufficiency as a whole; however, the gross distinction between "fatigue or stress fractures", on one side, and "fragility or insufficiency fractures", on the other, accepting the wide connotations of the corresponding terminology, is relevant to clinical practice. This article aims to explain the above biomechanical features and describe the different instances that predispose to "fatigue or stress fractures" in clinical practice, as a different entity from "insufficiency or fragility fractures" (maintaining this nomenclature), and describe their relevant features to their diagnosis and therapy. (AU)

Aspectos clínicos de las fracturas por stress / Clinical features of stress fractures

Las fracturas de stress son el resultado de la reiteración de cargas mecánicas en ciclos de intensidad, duración y frecuencia variables que, aplicadas como estímulos únicos, no serían suficientes para provocarlas. En líneas generales, el mecanismo propuesto para la generación de las fracturas de stress por fatiga es un desborde de la capacidad reparatoria de las microfracturas provocadas por las cargas de un exigente entorno mecánico, que corre a cargo de la remodelación ósea. Inicialmente fueron reportadas en el personal militar (en especial reclutas durante el período de instrucción) y luego en deportistas de diversas disciplinas que implican correr y/o saltar. Siendo esta la población primariamente en riesgo, se identificaron numerosos factores adicionales. En esta revisión se expondrán solamente aquellos de naturaleza endocrinometabólica y biomecánica. El síntoma inicial más frecuente de las fracturas por fatiga es el dolor focal, y su frecuencia es alta en los miembros inferiores. Se presenta al final de la actividad física, para luego extenderse a todo su curso y, finalmente, afectar también la deambulación diaria. El examen físico típicamente denota hipersensibilidad o dolor localizado sobre el área del hueso afectado, que a veces puede estar tumefacta. El diagnóstico se basa en las imágenes; la resonancia magnética nuclear es a de mayor sensibilidad y especificidad y la que permite un diagnóstico temprano, lo que es importante para prevenir un potencial progreso de la lesión a una fractura completa, osteosíntesis retardada o no unión, y necrosis ósea. (AU)

Stress fractures are the result of repeated cyclical loading whose intensity, duration and frequency are variable. These loads, applied as single stimuli, would not be enough to produce them. Overall, the proposed mechanism that generates fatigue fractures is an overflow in repair capacity, which is normally run by bone remodeling. They were first reported in military population (especially recruits during the training period) and later in athletes of various disciplines that involve running and / or jumping. This is primarily the population at risk. Other factors have been identified, only endocrine, metabolic and biomechanical will be discussed. The most common initial symptom of fatigue fractures is focal pain and frequency is high in the lower limbs. They appear at the end of physical activity, then spread throughou their course, and ultimately affect the daily ambulation. Physical examination typically shows hypersensitivity or localized pain on the area of the affected bone, which can sometimes be swollen. Diagnosis is based on images. Nuclear magnetic resonance has the highest sensitivity and specificity and allows early diagnosis, what is essential to prevent a potential progression of injury to a complete fracture, delayed healing or nonunion and bone necrosis. (AU)

Prosthetic abutment influences bone biomechanical behavior of immediately loaded implants

Abstract This study aimed to evaluate the influence of the type of prosthetic abutment associated to different implant connection on bone biomechanical behavior of immediately and delayed loaded implants. Computed tomography-based finite element models comprising a mandible with a single molar implant were created with different types of prosthetic abutment (UCLA or conical), implant connection (external hexagon, EH or internal hexagon, IH), and occlusal loading (axial or oblique), for both immediately and delayed loaded implants. Analysis of variance at 95%CI was used to evaluate the peak maximum principal stress and strain in bone after applying a 100 N occlusal load. The results showed that the type of prosthetic abutment influences bone stress/strain in only immediately loaded implants. Attachment of conical abutments to IH implants exhibited the best biomechanical behavior, with optimal distribution and dissipation of the load in peri-implant bone.

Plasmocitoma solitário do osso: relato e discussão de um caso de acometimento incomum / Solitary plasmacytoma of the bone: report and discussion of a case of involvement unusual

Plasmocitoma é uma proliferação clonal e neoplásica de células plasmáticas. Paciente, sexo feminino, 51 anos, sem história de tabagismo e consumo de álcool mostrou leve inflamação e inchaço na gengiva vestibular do dente 48 com mobilidade grau I. Radiograficamente verificou--se a presença de imagem radiolúcida multilocular na região do ângulo mandibular. Durante a cirurgia confirmou-se a presença de uma lesão destacável, friável, contendo líquido acastanhado e purulento em seu interior. A lesão foi totalmente removida em conjunto com o dente 48. Ao exame histopatológico (HE), foi identificada uma neoplasia maligna caracterizada pela proliferação de células plasmocitoides pleomórficas com núcleos intensamente hipercromáticos. Estas células exibiam núcleo basofílico com notável distribuição irregular da cromatina. Para confirmar o diagnóstico procedeu a avaliação imuno-histoquímica, que mostrou positividade para Plasm cell e Lambda e negatividade para Kappa. Com base nestes resultados concluiu-se o diagnóstico de plasmocitoma solitário do osso.

Plasmacytoma is a clonal proliferation and neoplastic of plasma cells. Patient, female, 51 years old, no history of smoking and alcohol consumption showed mild inflammation and swelling in the oral gingiva of the tooth 48 with mobility grade I. Radiographically verified the presence of radiolucent and multilocular image in the region of the mandibular angle. During surgery confirmed the presence of a lesion detachable, friable, browned and containing purulent fluid inside. This lesion was removed fully together with the tooth 48. Histopathology (HE) was identified a malignant neoplasm characterized by proliferation of plasmacytoid cells intensely hyperchromatic and pleomorphic. These cells exhibited large basophilic nucleus with remarkable irregular chromatin distribution. To confirm the diagnosis proceeded immunohistochemistry evaluation which showed positivity for Plasma Cell and Lambda and negativity of Kappa. Based on these findings concluded the diagnosis of plasmacytoma.

Trabecular bone score: perspectives of an imaging technology coming of age / Escore de osso trabecular: perspectivas de um método de imagem em aprimoramento

The trabecular bone score (TBS) is a new method to describe skeletal microarchitecture from the dual energy X-ray absorptiometry (DXA) image of the lumbar spine. While TBS is not a direct physical measurement of trabecular microarchitecture, it correlates with micro-computed tomography (µCT) measures of bone volume fraction, connectivity density, trabecular number, and trabecular separation, and with vertebral mechanical behavior in ex vivo studies. In human subjects, TBS has been shown to be associated with trabecular microarchitecture and bone strength by high resolution peripheral quantitative computed tomography (HRpQCT). Cross-sectional and prospective studies, involving a large number of subjects, have both shown that TBS is associated with vertebral, femoral neck, and other types of osteoporotic fractures in postmenopausal women. Data in men, while much less extensive, show similar findings. TBS is also associated with fragility fractures in subjects with secondary causes of osteoporosis, and preliminary data suggest that TBS might improve fracture prediction when incorporated in the fracture risk assessment system known as FRAX. In this article, we review recent advances that have helped to establish this new imaging technology.

TBS (do inglês, “trabecular bone score”) é um novo método que estima a microarquitetura óssea a partir de uma imagem de densitometria óssea (DXA) da coluna lombar. Apesar de o TBS não ser uma medida física direta da microarquitetura trabecular, ele correlaciona-se com o volume ósseo, densidade da conectividade trabecular, número de trabéculas e separação trabecular medidos por microtomografia computadorizada (µCT), e com medidas mecânicas da resistência óssea vertebral em estudos ex vivo. Estudos em humanos confirmaram que o TBS associa-se a microarquitetura trabecular e resistência óssea medidas por tomografia computadorizada quantitativa periférica de alta resolução (HRpQCT). Estudos transversais e prospectivos, envolvendo um grande número de indivíduos, mostraram que o TBS é associado com fratura vertebral, de colo de fêmur e com outros tipos de fraturas osteoporóticas em mulheres na pós-menopausa. Dados em homens, apesar de escassos, mostram resultados semelhantes. Além disso, o TBS foi associado a fraturas por fragilidade em indivíduos com diversas causas secundárias de osteoporose e, dados preliminares, sugerem que o uso do TBS pode melhorar a previsão de fratura quando incorporado ao sistema de avaliação de risco de fratura (FRAX). Este artigo faz uma revisão de avanços recentes que têm ajudado a estabelecer esse novo método de imagem.

Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)-based scaffolds for tissue engineering

Development and selection of an ideal scaffold is of importance for tissue engineering. Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) is a biocompatible bioresorbable copolymer that belongs to the polyhydroxyalkanoate family. Because of its good biocompatibility, PHBHHx has been widely used as a cell scaffold for tissue engineering. This review focuses on the utilization of PHBHHx-based scaffolds in tissue engineering. Advances in the preparation, modification, and application of PHBHHx scaffolds are discussed.

Oseopercepción: una puesta al día / Osseoperception: an update

La incorporación de implantes dentales al Sistema Estomatognático genera muchos cuestionamientos, entre ellos: ¿Cómo se explica que el paciente “sienta” a través de estos sistemas de anclaje?; ¿Por qué el paciente dice que mastica mejor que con las prótesis mucosoportadas?;¿Por qué a pesar de haber perdido dos componentes fisiológicos esenciales (dientes y periodonto) no se aprecian clínicamente importantes problemas dentro del sistema?; ¿Qué reordenamientos del sistema nervioso determinan la regulación motora luego de rehabilitado con estas técnicas? Es probable que las respuestas surjan a través del conocimiento de una nueva modalidad sensorial descriptacomo oseopercepción, la cual implica un reordenamiento de las áreas sensitivas y motoras de la corteza cerebral (neuroplasticidad).

Many questions arise from the introduction of dental implants into the stomatognathic system, for example: How can patients “feel” through these anchorage structures? Why does the patient feel that his mastication is improved with respect to the classic complete dentures? Why there are not remarkable alterations in the function of the stomatognathic system despite the loss of two essential componentsof this system? What rearrangements of the nervous system take place after the placement of dental implants that control the motor regulation of the stomatognathic system? Probably, the answer to these questions may come from the study of a new sensorymodality known as osseoperception, which involves a rearrangement of sensory and motor areas of the brain cortex (neuroplasticity).

Propranolol prevents osteoporosis and up-regulates leptin in ovariectomized rats

Osteoporosis is a systemic skeletal disease and there is a close relationship between the sympathetic nervous system [SNS] and bone metabolism. Leptin has been shown to regulate bone formation and bone resorption via the SNS. However, the effect of SNS on leptin signaling has not been clearly understood. In the present study, we studied the effect of propranolol on ovariectomy-induced osteoporosis of rat. The results showed propranolol could increase the bone mass of ovariectomized rat. Propranolol could also up-regulate the level of peripheral leptin and the level of leptin receptor in ovariectomized rat hypothalamus. Our results indicate the effect of propranolol on ovariectomy-induced osteoporosis may be exerted, at least partly, through the regulation of leptin signaling and there may be an interaction between the SNS and leptin on the regulation of bone metabolism

Análise comparativa entre o aloenxerto ósseo liofilizado, aloenxerto ósseo congelado e enxerto autógeno: estudo histológico em coelhos / Comparative analysis of demineralized freeze-dried bone, fresh frozen bone allograft and autogenous bone graft: a histologic study in rabbits

Considerando as diferentes aplicações clínicas dos enxertos ósseos nas reconstruções alveolares e a dificuldade de se obter ganhos ósseos em altura, o presente estudo avaliou do ponto de vista histológico a integração do enxerto autógeno (AU), do aloenxerto ósseo liofilizado desmineralizado (ALD), do aloenxerto ósseo congelado mineralizado (ACM) e do coágulo sanguíneo (CO) em um modelo de regeneração óssea vertical. Foram utilizados nove coelhos, sendo um animal doador primário de enxertos ósseos e oito animais submetidos a um modelo de regeneração óssea guiada (ROG), onde 32 cilindros de titânio foram fixados na calota craniana e preenchidos aleatoriamente com AU, ALD, ACM e CO. Após 13 semanas, os animais sofreram eutanásia e o conteúdo dos cilindros submetido à avaliação histológica e histomorfometrica para quantificar a área total de tecido neoformado (AT), o osso neoformado (ON) e o remanescente do material enxertado (MR). Os dados foram submetidos aos testes t-Student e Mann-Whitney com nível de significância de 5%. Os resultados mostraram que em relação à AT os valores médios foram significantes para ACM e ALD e seguiram a seguinte relação: ACM = ALD > AU > CO. Para a variável neoformação óssea as intervenções ALD e ACM mostraram maior quantidade de tecido ósseo formado do que as que empregaram osso autógeno ou coágulo. Já em relação à MR, a média da variável obedeceu à relação: ACM > ALD = AU = CO (valores-p < 5%). Todas as intervenções apresentaram médias mais significativas de crescimento tecidual nas regiões mais próximas ao leito receptor. Foi possível concluir que os aloenxertos podem ser considerados soluções adequadas para o crescimento ósseo vertical.

Regarding different clinical applications for bone grafts in alveolar reconstructions and difficulties on achieving vertical osseous increase the present study performed a comparative histological evaluation of demineralized freeze-dried bone allograft (DFDBA), of fresh frozen bone allograft (FFBA), autogenous graft (AU) and blood clot (CO) on vertical guided bone regeneration (GBR) in rabbit calvarium. Nine rabbits were used, with one as the primary bone graft donor and eight that were subjected to a model of GBR, whereby 32 titanium cylinders were fixed to the calvaria and randomly filled with DFDBA, FFBA, AU, or CO. The animals were sacrificed 13 weeks later, and the content of the cylinders was subjected to hitomorphological and histomorphometric analysis to quantify the total area of neoformed tissue (AT), the new bone tissue (NB) and residual graft particles (RG). The results showed that mean values for AT were significant to DFDBA and FFBA and followed the relation DFDBA = FFBA > AU > CO. Considering new bone formation DFDBA and FFBA showed better results than the AU and CO. The amount of residual bone particles was larger in the DFDBA and followed the relation FFBA > DFDBA = AU = CO (pvalues < 5%). All interventions showed greater new tissue formation nearby the receptor site. It was possible to conclude that allografts DFDBA and FFBA can be considered good strategies for new bone formation in vertical increasing bone.