Thuane Da Roza

An approach on determining the displacements of the pelvic floor during voluntary contraction using numerical simulation and MRI.

The present study was conducted in order to establish a methodology based on the finite element method to simulate the contraction of the pelvic floor (PF) muscles. In the generated finite element model, a downward pressure of 90 cm H2O was applied, while actively contracting the PF muscles with different degrees of muscular activation (10, 50 and 100%). The finite element methodology of the active contraction behaviour proposed in this study is adequate to simulate PF muscle contraction with different degrees of muscular activation. In this case, in particular, for an activation of 100%, the numerical model was able to displace the pubovisceral muscle in a range of values very similar to the displacement found in the magnetic resonance imaging data. In the analysed case study, it would be possible to conclude that an intensity contraction of 50% would be necessary to produce enough stiffness to avoid possible urine loss.

Football practice and urinary incontinence: Relation between morphology, function and biomechanics

Current evidence points to a high prevalence of urinary incontinence among female athletes. In this context, this study aims to assess if structural and biomechanical characteristics of the pubovisceral muscles may lead to urine leakage. Clinical and demographic data were collected, as well as pelvic Magnetic Resonance Imaging. Furthermore, computational models were built to verify if they were able to reproduce similar biomechanical muscle response as the one measured by dynamic imaging during active contraction by means of the percent error. Compared to the continent ones (n=7), incontinent athletes (n=5) evidenced thicker pubovisceral muscles at the level of the midvagina (p=0.019 and p=0.028 for the right and left sides, respectively). However, there were no differences neither in the strength of contraction in the Oxford Scale or in the displacement of the pelvic floor muscles during simulation of voluntary contraction, which suggests that urine leakage may be related with alterations in the intrafusal fibers than just the result of thicker muscles. Additionally, we found similar values of displacement retrieved from dynamic images and numerical models (6.42 ± 0.36 mm vs. 6.10 ± 0.47 mm; p=0.130), with a percent error ranging from 1.47% to 17.20%. However, further refinements in the mechanical properties of the striated skeletal fibers of the pelvic floor muscles and the inclusion of pelvic organs, fascia and ligaments would reproduce more realistically the pelvic cavity.

Translation of biomechanics research to urogynecology

IntroductionPelvic floor (PF) dysfunctions represent a frequent and complex problem for women. The interaction between the vagina and its supportive structures, that are designed to support increases in abdominal pressure, can be considered a biomechanical system. Recent advances in imaging technology have improved the assessment of PF structures. The aim of this paper is to review the applications of biomechanics in urogynecology.MethodsThe available literature on biomechanics research in urogynecology was reviewed.ResultsComputational models have been demonstrated to be an effective tool to investigate the effects of vaginal delivery and PF dysfunctions. Biomechanical analysis of PF tissues provides a better understanding on PF dysfunctions etiology. These studies are also important for the development of synthetic prostheses utilized in PF surgery.ConclusionAn interdisciplinary and multidisciplinary collaborative research, involving bioengineers and clinicians, is crucial to improve clinical outcomes in patients with PF dysfunctions.

Moment of inertia as a means to evaluate the biomechanical impact of pelvic organ prolapse

To present an alternative measure (moment of inertia) to describe the anatomical features of the pelvic organ prolapse.

Magnetic resonance imaging of the pelvic floor: From clinical to biomechanical imaging:

This article reviews the current role of magnetic resonance imaging in the study of the pelvic floor anatomy and pelvic floor dysfunction. The application of static and dynamic magnetic resonance imaging in the clinical context and for biomechanical simulation modeling is assessed, and the main findings are summarized. Additionally, magnetic resonance–based diffusion tensor imaging is presented as a potential tool to evaluate muscle fiber morphology. In this article, focus is set on pelvic floor muscle damage related to urinary incontinence and pelvic organ prolapse, sometimes as a consequence of vaginal delivery. Modeling applications that evaluate anatomical and physiological properties of pelvic floor are presented to further illustrate their particular characteristics. Finally, finite element method is described as a method for modeling and analyzing pelvic floor structures’ biomechanical performance, based on material and behavioral properties of the tissues, and considering pressure loads that mimic real-life conditions such as active contraction or Valsalva maneuver.

Vaginal Tissue Properties versus Increased Intra-Abdominal Pressure: A Preliminary Biomechanical Study

Background/Aims: This study aims to evaluate the pelvic floor (PF) tension response during simulated increased intra-abdominal pressure (IAP) and the vaginal biomechanical properties. Methods: A 3-dimensional computational finite element model for PF was developed based on magnetic resonance imaging from a nulliparous healthy volunteer. The model was used to simulate an IAP of 90 cm H2O and to evaluate the PF stresses in the longitudinal and transversal axes. The vaginal samples were obtained from 15 non-prolapsed female cadavers. A uniaxial tensile test to obtain stiffness and maximum stress of vaginal tissue in the longitudinal and transversal axes was performed. Results: The simulated IAP was associated with a similar PF stress state in the longitudinal and transversal axes. The stiffness and maximum stress in vaginal tissues presented a great variability between subjects. There was no difference in the vaginal tissue elasticity (6.2 ± 1.5 vs. 5.4 ± 1.1 MPa; p = 0.592) and maximum stress (2.3 ± 0.5 vs. 2.6 ± 0.9 MPa; p = 0.692) regarding the measurements in the longitudinal and transversal axes. Conclusion: The isotropic biomechanical behavior of vagina is in agreement with the PF stress state response during increased IAP.

Urinary Incontinence in Physically Active Young Women: Prevalence and Related Factors

This cross-sectional survey aims to (1) verify the prevalence of urinary incontinence and its impact on the quality of life among nulliparous fit women, and to (2) analyze whether urinary incontinence is influenced by the intensity of the sport (high- vs. low-impact) or by the volume of physical activity (minutes per week) performed. Two hundred forty-five nulliparous women (18-40 years) completed the International Consultation on Incontinence Questionnaire-Short Form, the Kings Health Questionnaire and a questionnaire regarding demographic and training variables. Overall 22.9% of the participants self-reported urinary incontinence, and among them, 60.7% had stress urinary incontinence. Incontinent women demonstrated worse quality of life than continent females (p=0.000). Women practicing high-impact sports presented higher frequency in loss of urine than those practicing low-impact sports (p=0.004). Regardless the intensity of the sport, the volume of exercise showed positive association with the frequency of loss of urine (p=0.005, r=0.475). In conclusion, almost one fourth of the women enrolled in this study reported symptoms of urinary incontinence and worse quality of life than those who were continent. Women who practice high-impact sports or who have higher volume of training should be aware of the symptoms associated with pelvic floor dysfunction, since they seem to predispose to urine leakage.

What Exists in the Scientific Literature About Biomechanical Models in Pelvic Floor?—a Systematic Review

To date, several relevant models to the female pelvic support system have been built. Recently, scientific literature has demonstrated biomechanical models as an alternative to better understand and assess the pelvic floor muscles. Biomechanical modelling is a useful approach for investigate the association between pelvic floor defects and stress urinary incontinence or prolapse. Computational models are already a reality and in the future may represent a significant tool for the study of pelvic floor pathophysiology. However, only a few studies used biomechanical models to assess the pelvic floor muscles.

A PERDA DE URINA É INFLUENCIADA PELA MODALIDADE ESPORTIVA OU PELA CARGA DE TREINO? UMA REVISÃO SISTEMÁTICA

En la actualidad, varios estudios senalan incontinencia urinaria (IU) entre las mujeres nuliparas jovenes y fisicamente activas. Sin embargo, algunos investigan la prevalencia de la IU segun las modalidades deportivas, mientras otros investigan la carga de entrenamiento. El proposito de este estudio fue verificar si la modalidad deportiva es mas decisiva en la prevalencia de la IU que la carga de entrenamiento entre las mujeres nuliparas jovenes. Para esta revision sistematica, tres revisores independientes realizaron una busqueda de las publicaciones originales en PubMed, LILACS y SciELO, entre 1994 y 2015. Se utilizaron como estrategia de busqueda las siguientes palabras clave: urinary incontinence AND (physical activity OR women OR nulliparous OR athletes), registradas en MeSH y DeCS. Se incluyeron solo los estudios originales publicados en los idiomas: portugues, ingles y espanol, que analizaron la IU en mujeres nuliparas, atletas o practicantes de actividad fisica. Se seleccionaron 873 estudios, pero solo diez articulos cumplieron los criterios de inclusion y exclusion. Todos los articulos fueron del tipo transversal, de los cuales cuatro relacionaron la IU con las modalidades deportivas, cinco analizaron la carga del entrenamiento con la perdida de orina y un estudio examino ambos aspectos. Se encontro una alta prevalencia de la IU entre los atletas. Parece haber evidencias de que las actividades que requieran saltar, largo aterrizaje y correr son las mas propensas a causar la perdida de orina. Ademas, la mayor carga de entrenamiento parece estar asociada con la cantidad de orina perdida. Esta revision destaca las altas tasas de IU en practicantes con grandes cargas de entrenamiento relacionadas con los deportes de salto, especialmente entre atletas. Sin embargo, todavia no hay respuesta sobre cual factor deportivo es mas decisivo para la perdida de orina en las mujeres nuliparas.

EFICÁCIA DA DINÂMICA DE GRUPO EM EDUCAÇÃO EM SAÚDE EM MULHERES COM INCONTINÊNCIA URINÁRIA

Introduction: Group dynamics is reported as a viable and cost-effective way to for promotion and health education among women. Objectives: Determine the level of knowledge about urinary incontinence among women who use the Public Health Network; verify the effectiveness of a health education protocol using group dynamics toward this population. Patients and Methods: We carried out a pilot study with application of a pre- and post-tests in six incontinent women. As a research instrument, we designed a health education and urinary incontinence questionnaires. We applied the questionnaires in late and immediate pre- and post-intervention periods. The meetings were based on an open group dynamics using lectures and recreational activities on topics related to urinary incontinence. Results: In the pre-intervention period, issues related to modifiable factors for the urinary incontinence treatment, as well as those related to the types of therapies used by physical therapists to treat incontinence of urine showed the highest percentage of error (83.3% of women). The participants showed a significant improvement in the level of knowledge regarding urinary incontinence from the pre-intervention moment to the immediate post-intervention moment (p = 0.005), as well as from the pre-intervention moment to the late post-intervention moment (p = 0.009). Conclusion: The present study showed that an open group dynamics using the proposed protocol was effective to improve the level of knowledge regarding urinary incontinence in women users of the Public Health Network in late and immediate post-intervention periods.