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During vaginal delivery, the fetal head molds into an elongated shape to adapt to the birth canal, a process known as fetal head molding. However, excessive molding can occur due to prolonged labor or strong contractions, leading to several disorders on the fetal head. This work aims to perform a numerical study on the biomechanics of fetal head molding by measuring specific diameters and the corresponding molding index. A finite element model of the pelvic floor muscles and the fetal body was used. The fetal head is composed of the skin and soft tissues, the skull with sutures and fontanelles, and the brain. The sutures and fontanelles were modeled with membrane elements and characterized by a visco‐hyperelastic constitutive model adapted to a plane stress state. Simulations were performed to replicate the second stage of labor in the vertex presentation and occipito‐anterior position. With the introduction of viscoelasticity to assess a time‐dependent response, a prolonged second stage of labor resulted in higher molding. The pressure exerted by the birth canal and surrounding structures, along with the presence of the pelvic floor muscles, led to a percentage of molding of 9.1%. Regarding the pelvic floor muscles, a 19.4% reduction on the reaction forces and a decrease of 2.58% in muscle stretching was reported, which indicates that sufficient molding may lead to fewer injuries. The present study demonstrates the importance of focusing on the fetus injuries with non‐invasive methods that can allow to anticipate complications during labor. [ABSTRACT FROM AUTHOR]

The main goal of this paper is to assess the mechanical damage in solid rigid foam materials with similar mechanical properties to the human bone induced by the cutting parameters. In the present study, a three-dimensional dynamic finite element model was developed to simulate the drilling process in solid rigid foam materials and it was validated with experimental results. Using an explicit dynamic numerical simulation, it is possible to obtain large structural deformation with high load intensity in short time frame. The developed model is used to study the effects of different high intensity loads distribution in the solid rigid foam materials. Laboratory tests were produced using biomechanical test blocks instrumented with strain gauges in different surface positions during the drilling process. The comparison between the numerical and the experimental results enables the evaluation and improvements of the cutting process. It was concluded when the feed-rate is higher, the stresses and strains in the solid rigid foam material are lower. The developed numerical model proved to be a great tool in this kind of analysis and available to use in forthcoming tests. [ABSTRACT FROM AUTHOR]

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Purpose: Otosclerosis is a metabolic bone disease of the otic capsule that can cause the stapes fixation, resulting in conductive hearing loss or, in a profound sensorineural deafness threshold. Surgery is one of the possible treatments for the otosclerosis. To repair small focus of otosclerosis in the anterior crus of the stapes, in 1960, Hough suggested the implementation of a technique in which part of the anterior crus is fractured and the stapes turned. As a result, the posterior crus of the stapes is the only connection with the inner ear. In this work, the outcome of Hough's surgical technique was simulated. Methods: Based on computerized images, a finite element model of middle ear ossicles and tympanic membrane was created, as well as a model where the stapes has changed. The discretization of the tridimensional solid model was made using the ABAQUS software. The mechanical properties used were taken from the literature and adequate boundary conditions were applied. Results: The results obtained with the Hough technique simulation were compared with a representative model of the normal ear, taking into account the displacements obtained on the central part of the stapes footplate and the maximum principal stress in the stapes crus. Conclusions: The results obtained are closer to the normal ear model, therefore Hough technique stands out as a good option to correct small focus of otosclerosis. [ABSTRACT FROM AUTHOR]

Introduction: Tinnitus is an auditory sensation whose source comes from external stimulus to the body. All studies that can help people with this disorder are very imperative. Objective: This study investigates the cochlear function in patients with tinnitus, using Distortion Products Otoacoustic Emissions (DPOAE). Material and Methods: Ears where the subjects referred to feel the tinnitus were considered for the study group while other ears without this sensation of tinnitus acted as a control group. Fifty subjects suffering from unilateral or bilateral tinnitus with normal hearing sensitivity or mild hearing loss were recruited. Results and conclusions: Where comparing the control and study group, the highest percentage of cases of DPOAE detected was in the control group, although these differences were not statistically significant. When the analyzed frequency is the same as the tinnitus frequency, the prevalence of detected DPOAE is in tinnitus ears (50.0 %). In ears where tinnitus was not perceived (73.5 %) a p value of 0.024 (< 0.05) was found, which means that the undetected DPOAE could be influenced by tinnitus. Based on the results, tinnitus might not be caused by changes in the outer hair cells but seems to be affected by that. [ABSTRACT FROM AUTHOR]

Copyright of Revista Iberoamericana de Ingeniería Mecánica is the property of Editorial UNED and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Urinary incontinence (UI) is defined as any involuntary urine loss that predominantly affects older women. There is evidence that pelvic floor muscles training (PFMT) program is effective on the treatment of pelvic floor (PF) dysfunctions and is considered to be first-line treatment. The evaluation of pelvic floor muscles (PFM) function and strength is central to validate the effectiveness of the training protocol in UI decrease. The Oxford Grading Scale and manometry are fundamental to evaluate the PFM function and strength., Objective: The aim of the study was to systematize the scientific evidence about the effects of PFMT in older women, assessing the PF function and strength through Oxford Grading Scale and manometry., Methods: The research of randomized controlled clinical trials was performed through B-on, EBSCO, PEDro, Pubmed, and SciELO data carried out from 2003 to 2016., Results: A total of 35 studies were identified, 26 of these were selected and fully analyzed. From the analyzed studies (n = 26), 20 were excluded for not meeting the criteria for inclusion, and only 6 studies were classified as high methodological quality, scoring an overall 4 points according the PEDro scale., Conclusion: The PFMT seems to be effective in treating UI in older women; the Oxford Grading Scale and manometry are considered the most reliable in the random and controlled clinical trials results. However, future investigations with high methodological quality with older women are necessary to support these results., Competing Interests: Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article.The authors report no conflicts of interest., (Copyright © 2018 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of PBJ-Associação Porto Biomedical/Porto Biomedical Society. All rights reserved.)