Efectos de la mastectomía en los parámetros baropodométricos de pacientes con cáncer de seno / The effect of mastectomy on baropodometric parameters for breast cancer patients / Efeitos da mastectomia nos parâmetros baropodometricos de pacientes com câncer de mama

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.

Functional tests and isokinetic knee assessment in street runner athletes correlation / Correlación entre pruebas funcionales y evaluación isokinética de rodilla en practicantes de carrera de calle / Correlação entre testes funcionais e avaliação isocinética do joelho em atletas corredores de rua

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.

Sport biomechanics before and after the rio 2016 paralympic games / Biomecánica del deporte antes y después de los juegos paralímpicos rio 2016 / Biomecânica do esporte antes e depois dos jogos paralimpícos rio 2016

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.

Assessing the effect of prophylactic ankle taping on ankle and knee biomechanics during landing tasks in healthy individuals: A cross-sectional observational study

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.

Riesgo de Caídas y Parámetros de Marcha en Personas Mayores de la Comunidad: ¿Cuáles son los Indicadores de Función y Disfunción del Movimiento? / Risk of Falls and Gait Parameters in Community Elderly: What Are the Indicators of Movement Function and Dysfunction?

Introducción. La población de personas mayores (PM) en Chile presenta un incremento sostenido con importantes tasas de fragilidad y riesgo de caídas (RC). El desempeño de marcha permite valorarlo mediante parámetros mecánicos y fisiológicos. Nos preguntamos, ¿cuáles podrían ser los más relevantes para estimar RC en condiciones de marcha confortable (MC) y máxima (MM)? Objetivo. Identificar los principales parámetros de marcha que podrían explicar RC en PM autovalentes de la comunidad. Métodos. Estudio observacional y transversal en el cual participaron 53 PM autovalentes de la comuna de Talca, Chile (edad 71±7años; IMC 29,1±3,4 kg/m2). Se solicitó a los participantes la ejecución de MC (n=53) y posteriormente MM (n=36). Ambas modalidades fueron desarrolladas en un circuito elíptico de 40m durante 3min. El RC se categorizó como: "sin riesgo", "riesgo dinámico" según prueba timed up and go (TUG) positiva, "riesgo estático" según estación unipodal (EUP) positiva y "riesgo mixto" con ambas pruebas positivas. Para la visualización de la variación gráfica en el morfoespacio de los individuos según RC, se realizó un análisis de componentes principales (ACP) mediante el Programa RStudio, utilizando 6 variables cinemáticas: i) velocidad promedio de marcha (VPM), ii) cadencia, iii) máximo despeje del pie (MDP), iv) coeficiente de variación (%CV) del MDP, v) longitud de zancada (LZ) y vi) %CV de la LZ. Además de 2 variables fisiológicas: i) % frecuencia cardiaca de reserva utilizada (%FCRu) y ii) el índice de costo fisiológico según la relación entre FC y VM (latidos/metros). Resultados. Para MC las dimensiones del ACP explican el 56% de la variabilidad de los datos, siendo los indicadores de seguridad de RC la VM, cadencia, LZ y MDP. La variabilidad de marcha explica RC mixto y el ICF junto al %FCRu se asocian a RC dinámico. En condiciones de MM, el ACP explica 60% de la variabilidad de datos, donde las PM sin RC se asocian con VM, LZ y MDP. Por su parte, la variabilidad del MDP se vincula con RC dinámico y las variables fisiológicas con el RC mixto. Conclusiones. Los parámetros de marcha que mejor explican una marcha segura y eficiente son cinemáticos de la fase de balanceo, mientras que la variabilidad y el costo fisiológico se asocian como indicadores de RC dinámico y mixto.

Background. Introduction: The elderly population (EP) in Chile is experiencing a sustained increase with significant rates of frailty and risk of falls (RF). Gait performance can be assessed using mechanical and physiological parameters. We wonder, which ones could be the most relevant to estimate RF in self-selected walking speed (SSWS) and maximum walking speed (MWS) conditions? Objective. Identify the main gait parameters that could explain RF in self-sufficient elderly individuals from the community. Methods. This observational and cross-sectional study included 53 self-sufficient elderly individuals from the commune of Talca, Chile (age 71±7 years; BMI 29.1±3.4 kg/m2). Participants were asked to perform SSWS (n=53) and subsequently MWS (n=36). Both modalities were conducted on a 40m elliptical circuit for 3 minutes. RF was categorized as: "no risk," "dynamic risk" based on a positive timed up and go test, "static risk" based on a positive one-legged stance test, and "mixed risk" with both tests positive. To visualize the graphical variation in the morphospace of individuals according to RF, a principal component analysis (PCA) was conducted using RStudio, utilizing 6 kinematic variables: i) walking speed (WS), ii) cadence, iii) maximum foot clearance (MFC), iv) coefficient of variation (%CV) of MFC, v) stride length (SL), and vi) %CV of SL. In addition to 2 physiological variables: i) % of reserve heart rate used (%RHRu) and ii) the physiological cost index based on the relationship between heart rate and WS (heartbeats/meters). Results. For SSWS, the PCA dimensions explained 56% of the data variability, with gait safety indicators such as WS, cadence, SL, and MFC explaining RF. Gait variability explains mixed RF, while the physiological cost index and %RHRu are associated with dynamic RF. In MWS conditions, PCA explains 60% of the data variability, where the elderly persons without RF are associated with WS, SL, and MFC. On the other hand, MFC variability is related to dynamic RF, and physiological variables are associated with mixed RF. Conclusions. The gait parameters that best explain safe and efficient walking are kinematic parameters of the swing phase, while variability and physiological cost are indicators of dynamic and mixed RF.

Effect of fried sunflower oil intake on mandibular biomechanical competence of growing rats / Efecto del consumo de aceite de girasol termooxidado sobre la competencia biomecánica de la mandíbula, en animales en crecimiento

ABSTRACT Previous studies by us demonstrated that the consumption of thermally oxidized oil diet adversely affects body growth, lipid metabolism, bone mass and femur biomechanical competence. Aim: The aim of this study was to evaluate the effects of a diet containing fried sunflower oil on the mandible of growing rats. Materials and Method: Male Wistar rats (21±1 day old) (n=21) were assigned at weaning to one of three diets for 8 weeks: a control diet (C), a diet containing sunflower oil (SFO) or a diet containing sunflower oil that had been repeatedly heated (SFOx); both SFO and SFOx were mixed with commercial rat chow at 13% (w/w). The consistency and viscosity of the 3 diets were similar. Zoometrics and food intake were recorded weekly. At wk=8, mandibular growth was assessed by measurements of anatomical points of cleaned bones, and mandible biomechanical competence was assessed to estimate the structural properties of the bone. Statistical analysis was performed by SPSS v. 20.0. Results: Rats fed SFOx diet attained the lowest final body weight (P=0.0074), mandibular weight (P=0.0001) and mandibular /length (P=0.0002). Load bearing capacity (Wf;N), load of yielding (Wy;N) and stiffness (Wy/dy;N/mm) of the mandible were negatively affected by both sunflower oil diets (fresh and fried) (P=0.001; P=0.002; P=0.003, respectively) though SFOx induced the most significant reduction in Wy/dy (C:44.4(5.4) > SFO:36.1(2.1) > SFOx: 26.3(3.7) N/ mm; P=0.003). The deleterious effect of SFOx on mandibular growth was more accentuated on the posterior part of the bone (C:11.4(0.3)=SFO:11.2(0.2)>SFOx: 10.7(0.2) mm; p=0.0005); the anterior/ posterior ratio (C:1.25(0.02)=SFO:1.27(0.02)<SFOx:1.32(0.03); p=0.0001) indicated that SFOx induced mandibular deformation. Conclusion: Consumption of SFOx diet during growth could affect mandibular morphometric properties and biomechanical competence, in terms of bone stiffness.

RESUMEN En estudios previos hemos demostrado los efectos adversos del consumo de una dieta rica en aceite termooxidado sobre el crecimiento corporal, el metabolismo de los lípidos, la masa ósea y la competencia biomecánica del fémur. Objetivo: El objetivo de este trabajo fue investigar el efecto de una dieta rica en aceite de girasol termooxidado (AGX) sobre los parámetros morfométricos y biomecánicos de la mandíbula de rata en crecimiento. Materiales y Método: Ratas macho Wistar de 22±1 días de edad (n=21) recibieron durante 8 semanas una de 3 dietas: control (C); dieta comercial, una dieta suplementada con aceite de girasol (AG) y una dieta suplementada con AGX. La consistencia y la viscosidad de las dietas fueron similares. Los parámetros zoométricos y el consumo de dieta se registraron semanalmente. A T=8, los animales se eutanasiaron y se obtuvieron las hemimandíbulas. El crecimiento mandibular se estimó por medidas morfométricas entre puntos anatómicos y las propiedades estructurales por biomecánica. El análisis estadístico se realizó por SPSS v. 20.0. Resultados: Las ratas alimentadas con AGX presentaron menor peso corporal final (p=0.0074), peso mandibular (p=0.0001) y longitud mandibular (p=0.0002). Las propiedades estructurales de la mandíbula, Wf (p=0.001), Wy (p=0.002) y Wy/dy (p=0.003), se vieron afectadas negativamente en ratas alimentadas con AG o AGX, respecto a C; pero la rigidez ósea (Wy/dy) en AGX fue significativamente menor (C:44.4(5.4) > SFO:36.1(2.1) > SFOx: 26.3(3.7) N/mm; p=0.003). El efecto deletéreo del AGX sobre el crecimiento mandibular fue más acentuado en la región posterior (C:11.4(0.3)=SFO:11.2(0.2)>SFOx: 10.7(0.2) mm; p=0.0005). La relación anterior/posterior (C=1.25 (0.02); AG= 1.27(0.02) y AGX=1.32(0.03), p=0.001) indica que AGX indujo deformación mandibular. Conclusiones: El efecto adverso del consumo de una dieta rica en AGX durante el crecimiento podría afectar los parámetros morfométricos y la biomecánica ósea en términos de rigidez ósea.

Age-related variations in corneal stress-strain index in the Indian population

Purpose: To report age?related variations in corneal stress–strain index (SSI) in healthy Indians. Methods: It was a retrospective study where healthy Indian individuals aged between 11 and 70 years who had undergone corneal biomechanics assessment using Corvis ST between January 2017 and December 2021 were enrolled. Composite corneal biomechanical parameters and corneal SSI were abstracted from Corvis ST and compared across different age groups using one?way analysis of variance (ANOVA). Also, Pearson’s correlation was used to evaluate the association between age and SSI. Results: Nine hundred and thirty?six eyes of 936 patients with ages between 11 and 77 years with mean ± SD intraocular pressure (IOP) and pachymetry of 16.52 ± 2.10 mmHg and 541.13 ± 26.39 ?s, respectively. Composite corneal biomechanical parameters such as deformation amplitude ratio max at 1 mm (P < 0.001) and 2 mm (P < 0.001), biomechanically corrected IOP (P = 0.004), stiffness parameter at A1 (P < 0.001, Corvis biomechanical index (P < 0.018), and SSI (P < 0.001) were found to be significantly different as a function of age group. We noted a statistically significant positive association of SSI with age (P < 0.001), spherical equivalent refractive error (P < 0.001), and IOP (P < 0.001) and a significant negative association with anterior corneal astigmatism (P < 0.001) and Anterior chamber depth (ACD) (P < 0.001). Also, SSI was positively associated with SPA1 and bIOP, whereas negatively associated with integrated radius, max inverse radius, and Max Deformation amplitude (DA) ratio at 1 mm and 2 mm. Conclusion: We noted a positive association of corneal SSI with age in normal healthy Indian eyes. This information could be helpful for future corneal biomechanical research.

Biomechanical Gait Analysis in Patients with Osteonecrosis of the Femoral Head / Análise biomecánica da marcha de pacientes com osteonecrose da cabeça do fémur

Abstract Objectives Although osteonecrosis of the femoral head is a prevalent condition, its effects on gait parameters have not been thoroughly studied and are not well-established in the current literature. The primary aim of the present study is to describe gait in patients with a diagnosis of osteonecrosis. Methods This is a cross-sectional study. Nine patients diagnosed with osteonecrosis of the femoral head who were regularly followed-up at an outpatient clinic were selected for the present study and underwent gait analysis using Vicon Motion Capture Systems. Spatiotemporal data was obtained, and joint angles were calculated using an Euler angle coordinate system. Distal coordinate systems were used to calculate joint momentsand forceplatestoobtaingroundreactionforces. Results Patients with osteonecrosis presented with slower velocity (0.54 m/s ± 0.19) and smaller cadence (83.01 steps/min ± 13.23) than healthy patients. The pelvic obliquity range of motion was of 10.12° ± 3.03 and rotation was of 18.23° ± 9.17. The mean hip flexion was of 9.48° ± 3.40. Ground reaction forces showed reduced braking and propelling forces. Joint moments were reduced for flexion and adduction (0.42 Nm/kg ± 0.2 and 0.30 Nm/kg ± 0.11, respectively) but the abduction moment was increased (0.42 Nm/kg ± 0.18). Conclusions The present study showed that osteonecrosis of the femoral head presents compensatory gait mechanisms, with increased pelvic motion and decreased knee flexion to protect the hip joint. Decreased moments for hip flexion and adduction were also identified and muscle weakness for those groups may be correlated to the disease.

Resumo Objetivos Embora a osteonecrose da cabeça do fêmur seja uma lesão prevalente, seus efeitos sobre os parâmetros da marcha não foram minuciosamente estudados e não estão bem estabelecidos na literatura atual. O objetivo principal do presente estudo é descrever a marcha em pacientes com osteonecrose. Métodos Trata-se de um estudo transversal. Nove pacientes com diagnóstico de osteonecrose da cabeça do fêmur, sob acompanhamento regular em ambulatório, foram selecionados para o presente estudo e submetidos à análise da marcha com Vicon Motion Capture Systems. Os dados espaciais e temporais foram obtidos e os ângulos articulares foram calculados com o sistema de coordenadas angulares de Euler. Sistemas de coordenadas distais e plataformas de força foram utilizados para o cálculo de momentos articulares e de forças de reação ao solo, respectivamente. Resultados Os pacientes com osteonecrose apresentaram menor velocidade (0,54 m/s ± 0,19) e menor cadência (83,01 passos/minuto ± 13,23) do que pacientes saudáveis. As amplitudes de movimento de obliquidade e rotação pélvica foram de 10,12°± 3,03 e 18,23° ± 9,17, respectivamente. A média de flexão do quadril foi de 9,48° ± 3,40. O estudo das forças de reação ao solo revelou redução das forças de frenagem e propulsão. Os momentos articulares de flexão e adução caíram (0,42 Nm/kg ± 0,2 e 0,30 Nm/kg ± 0,11), mas o momento de abdução aumentou (0,42 Nm/kg ± 0,18). Conclusões O presente estudo mostrou que a osteonecrose da cabeça do fêmur é associada a mecanismos compensatórios da marcha, com aumento da movimentação pélvica e diminuição da flexão do joelho para proteção da articulação do quadril. A redução dos momentos de flexão e adução do quadril também foi identificada e a fraqueza destes grupos musculares pode estar correlacionada à doença.

Is there a Difference in Interfragmentary Compression Strength Between Fully or Partially Threaded Screws? Results of an Experimental Biomechanical Pilot Study / Há diferença na força de compressão interfragmentar entre parafusos com rosca total ou parcial? Resultados de um estudo biomecânico experimental piloto

Abstract Objective This study assessed differences between fully- and partially-threaded screws in the initial interfragmentary compression strength. Our hypothesis was that there would be an increased loss in initial compression strength with the partially-threaded screw. Methods A 45-degree oblique fracture line was created in artificial bone samples. The first group (FULL, n = 6) was fixed using a 3.5-mm fully-threaded lag screw, while the second group (PARTIAL, n = 6) used a 3.5-mm partially-threaded lag screw. Torsional stiffness for both rotational directions were evaluated. The groups were compared based on biomechanical parameters: angle-moment-stiffness, time-moment-stiffness, maximal torsional moment (failure load), and calibrated compression force based on pressure sensor measurement. Results After loss of one PARTIAL sample, no statistically significant differences in calibrated compression force measurement were observed between both groups: [median (interquartile range)] FULL: 112.6 (10.5) N versus PARTIAL: 106.9 (7.1) N, Mann-Whitney U-test: p = 0.8). In addition, after exclusion of 3 samples for mechanical testing (FULL n = 5, PARTIAL n = 4), no statistically significant differences were observed between FULL and PARTIAL constructs in angle-moment-stiffness, time-moment-stiffness, nor maximum torsional moment (failure load). Conclusion There is no apparent difference in the initial compression strength (compression force or construct stiffness or failure load) achieved using either fully-or partially-threaded screws in this biomechanical model in high-density artificial bone. Fully-threaded screws could, therefore, be more useful in diaphyseal fracture treatment. Further research on the impact in softer osteoporotic, or metaphyseal bone models, and to evaluate the clinical significance is required.

Resumo Objetivo Este estudo avaliou diferenças entre parafusos com rosca total ou parcial na resistência à compressão interfragmentar inicial. Nossa hipótese era de que haveria maior perda de resistência à compressão inicial com o parafuso de rosca parcial. Métodos Uma linha de fratura oblíqua de 45 graus foi criada em amostras de osso artificial. O primeiro grupo (TOTAL, n = 6) foi fixado com um parafuso de 3,5 mm de rosca total, enquanto o segundo grupo (PARCIAL, n = 6) usou um parafuso de 3,5 mm de rosca parcial. Avaliamos a rigidez à torção em ambas as direções de rotação. Os grupos foram comparados com base nos seguintes parâmetros biomecânicos: momento de rigidez-ângulo, momento de rigidez-tempo, momento de torção máxima (carga de falha) e força de compressão calibrada com base na medida do sensor de pressão. Resultados Depois da perda de uma amostra PARCIAL, não foram observadas diferenças estatisticamente significativas na força de compressão calibrada entre os 2 grupos [mediana (intervalo interquartil)]: TOTAL: 112,6 (10,5) N e PARCIAL: 106,9 (7,1) N, com p = 0,8 segundo o teste U de Mann-Whitney). Além disso, após a exclusão de 3 amostras para testes mecânicos (TOTAL, n = 5, PARCIAL, n = 4), não foram observadas diferenças estatisticamente significativas entre os construtos TOTAL e PARCIAL quanto ao momento de rigidez-ângulo, momento de rigidez-tempo ou momento de torção máxima (carga de falha). Conclusão Não há diferença aparente na força de compressão inicial (força de compressão ou rigidez do construto ou carga de falha) com o uso de parafusos de rosca total ou parcial neste modelo biomecânico em osso artificial de alta densidade. Parafusos de rosca total podem, portanto, ser mais úteis no tratamento de fraturas diafisárias. Mais pesquisas são necessárias sobre o impacto em modelos ósseos osteoporóticos ou metafisários de menor densidade e avaliação do significado clínico.

Monoaxial Mechanical Tests on Porcino Knee Ligaments / Ensaios mecânicos monoaxiais nos ligamentos do joelho porcino

Abstract The failure of ligament reconstruction has different risk factors, among which we can highlight the period before its incorporation, which is a mechanically vulnerable period. Loss of resistance over time is a characteristic of living tissues. Dissection with bone insertions of the cruciate ligaments of animal models is not described; however, it is essential for monoaxial assays to extract information from tests such as relaxation. The present work describes the dissection used for the generation of a test body for the performance of nondestructive tests to evaluate the mechanical behavior. We performed dissection of four porcino knee ligaments, proposing a dissection technique for the cruciate ligaments with bone inserts for comparison with collateral ligaments. The ligaments were submitted to relaxation tests and had strain gauges placed during the tests. The results showed viscoelastic behavior, validated by strain gauges and with a loss over time; with some ligaments presenting with losses of up to 20%, a factor to be considered in future studies. The present work dissected the four main ligaments of the knee demonstrating the posterior approach that allows maintaining their bone insertions and described the fixation for the monotonic uniaxial trials, besides being able to extract the viscoelastic behavior of the four ligaments of the knee, within the physiological limits of the knee.

Resumo A falha da reconstrução ligamentar tem diferentes fatores de risco, dentre os quais podemos destacar o período antes da sua incorporação, o qual configura um período mecânico vulnerável. A perda de resistência ao longo do tempo é uma característica dos tecidos vivos. A dissecção com as inserções ósseas dos ligamentos cruzados de modelos animais não é descrita; todavia, para os ensaios monoaxiais, é fundamental extrair as informações de ensaios como os de relaxação. O presente trabalho realiza a descrição da dissecção utilizada para a geração de corpo de prova para a realização de ensaios não destrutivos para avaliar o comportamento mecânico. Realizamos dissecção de quatro ligamentos de joelho porcino, propondo uma técnica de dissecção para os ligamentos cruzados com as inserções ósseas para comparação com os colaterais. Os ligamentos foram submetidos a testes de relaxação e foram colocadas strain gauges durante os testes. Os resultados mostraram comportamento viscoelástico, validado pelas strain gauges e com uma perda ao longo do tempo, sendo que, em alguns ligamentos, as perdas chegaram a até 20%, fator este a ser considerado em trabalhos futuros. O presente trabalho dissecou os quatro principais ligamentos do joelho, demonstrando a abordagem posterior que permite manter as suas inserções ósseas e descrevendo a fixação para os ensaios uniaxiais monotônicos, além de ter conseguido extrair o comportamento viscoelástico dos quatro ligamentos do joelho dentro dos limites fisiológicos do joelho.

Distocia de hombros: propuestas de resolución de acuerdo con las diferentes posiciones de parto según la movilidad de la pelvis

Introducción. La distocia de hombros es una complicación del parto vaginal que se produce por dificultad en el parto de los hombros fetales. Puede desencadenarse en forma impredecible e imprevista, por lo que debería ser considerada como riesgo potencial de todo nacimiento. La mayoría de las recomendaciones sobre las maniobras de resolución de distocia de hombros lo hacen desde la posición de litotomía y sin considerar los movimientos intrínsecos de la pelvis durante el parto. Objetivos. Analizar las maniobras de resolución de distocia de hombros a partir del conocimiento de la biomecánica de la pelvis y su relación con los hombros fetales, teniendo en cuenta las diferentes posiciones de parto. Métodos. Revisión bibliográfica no sistematizada. Resultados. Ante la distocia del hombro anterior, si la gestante se encuentra en litotomía podría recomendarse la maniobra de McRoberts con presión suprapúbica seguida de la extracción del brazo posterior. Si la gestante se encuentra en posición vertical, se sugiere pasar a posición de cuatro apoyos y una variante original resultado del análisis de los movimientos de la pelvis llamada 'cuatro apoyos en asimetría'. Esta puede ser realizada desde cualquier posición, no es invasiva y requiere un mínimo de entrenamiento. Conclusiones. La resolución de distocia de hombros no posee un único algoritmo; dependerá del tipo de distocia, la posición de la gestante, el contexto y la mayor o menor habilidad de una maniobra sobre otra. La postura de Gaskin y cuatro apoyos en asimetría debería ser tenida en cuenta antes de realizar maniobras internas para la resolución de la distocia de hombros.

Introduction: Shoulder dystocia is a complication of vaginal delivery caused by a difficulty in delivering the fetal shoulders. It can be triggered in an unpredictable and unplanned manner, so it should be considered as a potential risk for every vaginal birth. Most of the recommendations on shoulder dystocia resolution maneuvers are made from the lithotomy position and without considering the intrinsic movements of the pelvis during labor. Objectives : To analyze the maneuvers for resolving shoulder dystocia based on knowledge of the biomechanics of the pelvis and its relationship with the fetal shoulders, considering the different birthing positions. Methods: Non-systematized bibliographic review. Results : In the case of anterior shoulder dystocia, the McRoberts maneuver with suprapubic pressure followed by extraction of the posterior arm could be recommended for a birthing woman in lithotomy position. If the birthing woman is in an upright position, it is suggested to move to the four-support position and an original variant resulting from the analysis of the biomechanics of the pelvis called 'four-lying in asymmetry'. These maneuvers are non-invasive techniques, require minimal training and resources, and can be performed from any childbirth position. Conclusions : The resolution of shoulder dystocia does not have a single algorithm; it will depend on the type of dystocia, the position of the birthing woman, the context, and the greater or lesser ability of one maneuver over another. Gaskin maneuver and four supports in asymmetry should be considered before performing internal maneuvers for the resolution of shoulder dystocia.

Effect of ascorbic acid and epidermal growth factor in a rat tibia defect

Purpose: Bone repair aims to restore the anatomical, biomechanical, and functional integrity of the affected structure. Here we study the effects of ascorbic acid (AA) and epidermal growth factor (EGF) applied in a single dose and in combination on the repair of a noncritical bone defect model. Methods: Twenty-four rats were divided into four groups: an intact G-1 control group, and three groups that underwent a noncritical bone defect in the right tibia: G-2 treated with AA, G-3 treated with EGF, and G-4 treated with AA in combination with EGF. After 21 days of treatment, rats were sacrificed, the tibias were dissected and a destructive biomechanical analysis of three-point flexion test was performed in a universal testing machine; the values of stiffness, resistance, maximum energy, and energy at maximum load were statistically compared. Results: G-3 and G-4 recovered the biomechanical properties of strength and stiffness of an intact tibia 3 weeks after their application. Not so the energy and energy at maximum load. For G-2, only the stiffness of an intact tibia was recovered. Conclusion: EGF and AA-EGF applied to a noncritical bone defect in the rat tibia favors the recovery of bone resistance and stiffness.

Finite element analysis for predicting osteonecrosis of the femoral head collapse based on the preserved angles / 中国修复重建外科杂志

OBJECTIVE@#To establish finite element models of different preserved angles of osteonecrosis of the femoral head (ONFH) for the biomechanical analysis, and to provide mechanical evidence for predicting the risk of ONFH collapse with anterior preserved angle (APA) and lateral preserved angle (LPA).@*METHODS@#A healthy adult was selected as the study object, and the CT data of the left femoral head was acquired and imported into Mimics 21.0 software to reconstruct a complete proximal femur model and construct 3 models of necrotic area with equal volume and different morphology, all models were imported into Solidworks 2022 software to construct 21 finite element models of ONFH with LPA of 45°, 50°, 55°, 60°, 65°, 70°, and 75° when APA was 45°, respectively, and 21 finite element models of ONFH with APA of 45°, 50°, 55°, 60°, 65°, 70°, 75° when LPA was 45°, respectively. According to the physiological load condition of the femoral head, the distal femur was completely fixed, and a force with an angle of 25°, downward direction, and a magnitude of 3.5 times the subject's body mass was applied to the weight-bearing area of the femoral head surface. The maximum Von Mises stress of the surface of the femoral head and the necrotic area and the maximum displacement of the weight-bearing area of the femoral head were calculated and observed by Abaqus 2021 software.@*RESULTS@#The finite element models of ONFH were basically consistent with biomechanics of ONFH. Under the same loading condition, there was stress concentration around the necrotic area in the 42 ONFH models with different preserved angles composed of 3 necrotic areas with equal volume and different morphology. When APA was 60°, the maximum Von Mises stress of the surface of the femoral head and the necrotic area and the maximum displacement of the weight-bearing area of the femoral head of the ONFH models with LPA<60° were significantly higher than those of the models with LPA≥60° ( P<0.05); there was no significant difference in each index among the ONFH models with LPA≥60° ( P>0.05). When LPA was 60°, each index of the ONFH models with APA<60° were significantly higher than those of the models with APA≥60° ( P<0.05); there was no significant difference in each index among the ONFH models with APA≥60° ( P>0.05).@*CONCLUSION@#From the perspective of biomechanics, when a preserved angle of ONFH is less than its critical value, the stress concentration phenomenon in the femoral head is more pronounced, suggesting that the necrotic femoral head may have a higher risk of collapse in this state.

Biomechanical properties of epithelial mesenchymal transition in idiopathic pulmonary fibrosis / 生物医学工程学杂志

Idiopathic pulmonary fibrosis (IPF) is a progressive scar-forming disease with a high mortality rate that has received widespread attention. Epithelial mesenchymal transition (EMT) is an important part of the pulmonary fibrosis process, and changes in the biomechanical properties of lung tissue have an important impact on it. In this paper, we summarize the changes in the biomechanical microenvironment of lung tissue in IPF-EMT in recent years, and provide a systematic review on the effects of alterations in the mechanical microenvironment in pulmonary fibrosis on the process of EMT, the effects of mechanical factors on the behavior of alveolar epithelial cells in EMT and the biomechanical signaling in EMT, in order to provide new references for the research on the prevention and treatment of IPF.

Application of Biomechanical Stress from Coronary Computed Tomography Angiography in Coronary Plaque Assessment and Prediction of Adverse Cardiovascular Events / 医用生物力学

Long-term exposure to risk factors will lead to coronary atherosclerosis, which will lead to the formation and progression of coronary plaque. Early identification of high-risk plaque characteristics will help prevent plaque rupture or erosion, thus avoiding the occurrence of acute cardiovascular events. Biomechanical stress plays an important role in progression and rupture of atherosclerotic plaques. In recent years, non-invasive coronary computed tomography angiography (CCTA) computational fluid dynamics (CFD) modeling has made it possible to acquire the corresponding biomechanical stress parameters. These coronary biomechanical stress parameters, especially wall shear stress (WSS), will aid in the development of a more accurate clinical model for predicting plaque progression and major adverse cardiovascular events ( MACE ). In this review, the biomechanical stress and the role of WSS from CCTA in atherosclerosis were introduced, and the researches on the relationship between biomechanical stress from CCTA and coronary artery diseases were discussed.

Biomechanical CT for Assessment of Osteoporotic Vertebral Fracture Risk / 医用生物力学

Osteoporosis is characterized by decreased bone strength and increased fracture risk. The most serious consequence of osteoporosis is fracture, which commonly occurs in vertebrae. Accurate assessment of fracture risk at an earlier stage is the key to identify high-risk population and further prevent osteoporotic fracture. Currently, clinical assessment of vertebral fracture risk mainly relies on measurement of bone mineral density (BMD) based on dual energy X-ray absorptiometry ( DXA) or quantitative computed tomography ( QCT). However, they cannot fully reflect bone strength and resistance to fracture, and it is hard to achieve an accurate assessment. Biomechanical CT (BCT) technology, based on CT digital modeling and finite element analysis, aims at non-invasive calculation of individual bone strength, bridging the gap between biomechanics and clinical evaluation of fracture risk. In vitro mechanical experiment of vertebrae has proved that BCT is more accurate than BMD in evaluating vertebral fracture strength. Clinical studies have also shown that BCT is superior to DXA inidentifying existing fractures and predicting new fractures. In this article, the implementation process of the BCT technology was introduced, as well as critical parameters during each step affecting its result . The research progress of the BCT technique for in vitro validation and in vivo assessment of vertebral fracture risk was also summarized, with the aim to promote the application of BCT technology in clinical assessment of vertebral fracture risk for the Chinese people.

Anterolateral or Posteromedial Plate-Assisted Intramedullary Nailing for Fixation of Proximal Third Tibia Fractures: A Biomechanical Study / 医用生物力学

Objective To study the stability of plate-assisted intramedullary nailing for fixing proximal third tibiafractures, compare and observe biomechanical characteristics of anterolateral or posteromedial plate-assisted intramedullary nailing after fixation of proximal third tibia fractures. Methods Eight artificial tibia of 4th-generation sawbones were divided into two groups based on location of the assisted plate, namely, anterolateral plate group and posteromedial plate group, with 4 specimens in each group. Each two locking bolts were fixed to theintramedullary nail proximally and distally, and each three bicortical screws were fixed to the plate proximally and distally. The specimens were osteotomized with a 10-mm defect which located 0. 5 cm to the proximal locking bolt of intramedullary nail or 5-6 cm distally to the knee joint line, in order to simulate an AO/ OTA 41-A2 type proximal third tibia fracture after fixation of intramedullary nail. After osteotomy was finished, axial compression test, three point bending test, cyclic loading and overstress test were conducted by mechanical testing machine. The results of axial stiffness and three-point stiffness between two groups were compared and analyzed. Results Axial compression test showed that the average axial stiffness in posteromedial plate group was lower than that in anterolateral plate group, but no significantly statistical differences were found between the two groups. Three point bending test showed that the average bending stiffness in posteromedial plate group was significantly higher than that in anterolateral plate group when stimulating either varus stress (plate located at pressure side of the fracture, t = 3. 679, P<0. 05) or valgus stress (plate located at tension side of the fracture, t = 8. 975, P<0. 05). Conclusions Plate-assisted intramedullary nailing for fixation of proximal third tibia fractures can minimize the angulation malalignment, improve the stability of nailed proximal tibial fragment and allow the early weight bearing. Both anterolateral and posteromedial plate-assisted intramedullary nail can provide satisfactory axial stability for proximal third tibia fractures, while posteromedial plate-assisted intramedullary nail shows better bending stability than anterolateral plate in countering varus or valgus stress deformity. This study provides an essential basis for clinical decision making about plate-assisted intramedullary nailing for fixing proximal third tibia fractures.

Study on influencing factors of work-related musculoskeletal disorders in neck-shoulder-back of manufacturing workers / 中国职业医学

{L-End}Objective To investigate the influencing factors of work-related musculoskeletal disorders (WMSDs) that affect neck-shoulder-back among manufacturing workers. {L-End}Methods A total of 8 250 front-line workers from 27 manufacturing enterprises in Henan Province and Hubei Province were selected as the research subjects using cluster sampling method. The Musculoskeletal Disorders Questionnaire was used to investigate the prevalence of neck-shoulder-back (include neck, shoulder, upper back, and lower back) WMSDs in the past year. The log-binomial model, principal component analysis (PCA) and multivariate logistic regression analysis were used to analyze the influencing factors of WMSDs in the neck-shoulder-back. {L-End}Results The prevalence of WMSDs was 77.2%. The prevalence of neck-shoulder-back WMSDs was 50.9%. The prevalence ratios of WMSDs were relatively higher among the neck, shoulder, and upper back (all P<0.05). The results of PCA improved logistic regression analysis showed that the influencing factors of neck-shoulder-back WMSDs were individual factors, biomechanical factors, psychosocial factors and environmental factors. In terms of individual factors, the risk of neck-shoulder-back WMSDs was higher in females than in males (P<0.05). With the increase of age, length of service, and education level, the risk of neck-shoulder-back WMSDs increased among manufacturing workers (all P<0.05). The risk of neck-shoulder-back WMSDs of workers in textile, clothing, shoes and hats manufacturing industry was relatively lower than that in the other nine industries (all P<0.05). In terms of the biomechanical factors, spending a lot of effort to operate tools/machines, sitting for a long time at work,bending greatly bending and turning at the same time, neck leaning forward or maintaining this posture for a long time, neck twisting or maintaining this posture for a long time and uncomfortable position resulting in difficulty exerting exertion were all risk factors of neck-shoulder-back WMSDs among manufacturing workers (all P<0.05) Bending slightly for a long time was a protective factor for neck-shoulder-back WMSDs among manufacturing workers (P<0.05). In terms of the psychosocial factors, doing the same work every day, self-determination in resting time between works staff shortage, and frequent overtime work were risk factors for neck-shoulder-back WMSDs among manufacturing workers (all P<0.05). Adequate resting time was a protective factor for neck-shoulder-back WMSDs among manufacturing workers (P<0.01). In terms of environmental factors, working under cold or fluctuating temperature, having nothings to lean on, and soles slipping or falling at work were all risk factors for neck-shoulder-back WMSDs among manufacturing workers (all P<0.05). {L-End}Conclusion Manufacturing workers are prone to suffer from neck-shoulder-back WMSDs. The influencing factors include individual factors, biomechanical factors (force load and static load), psychosocial factors and environmental factors.

Biomechanical mechanism and treatment strategy of female bladder prolapse / 现代泌尿外科杂志

Bladder prolapse is a common disease in female,which seriously affects the physical and mental health of patients. At present,numerous treatment methods can improve the condition to some extent,but the therapeutic effect is still not satisfactory. This paper probes into the etiology of bladder prolapse from the perspective of biomechanics,explores the relationship between bladder prolapse and stress injury,and proposes corresponding treatment strategies for better management of this disease.

Research advances on pelvic floor deformation characteristics and biomechanical axial in apical suspension / 现代泌尿外科杂志

Female pelvic organ prolapse (POP) is caused by damage or loss of pelvic floor support, resulting in displacement of the pelvic organs, which leads to abnormalities in the position and function of the organs, mainly due to damage to the pelvic floor mechanical support structures caused by transvaginal birth, loss of elasticity of the pelvic floor mechanical support structures in old women, and loss of the ability to maintain the pelvic floor. The key to POP surgery is the repair of the apical vagina, but treatment based on this theory has failed to achieve satisfactory clinical outcomes. This article will analyze the common procedures of apical suspension in the treatment of mid-pelvic prolapse from the perspective of pelvic floor morphological features and pelvic floor biomechanics axially.