Birth progression and traction forces developed under vacuum extraction after slow or rapid application of suction

Author(s):  
Leif Svenningsen
1988 ◽  
Vol 16 (2-3) ◽  
pp. 263-269 ◽  
Author(s):  
Leif Svenningsen ◽  
Kristin Eidal

Author(s):  
Tim Oliver ◽  
Michelle Leonard ◽  
Juliet Lee ◽  
Akira Ishihara ◽  
Ken Jacobson

We are using video-enhanced light microscopy to investigate the pattern and magnitude of forces that fish keratocytes exert on flexible silicone rubber substrata. Our goal is a clearer understanding of the way molecular motors acting through the cytoskeleton co-ordinate their efforts into locomotion at cell velocities up to 1 μm/sec. Cell traction forces were previously observed as wrinkles(Fig.l) in strong silicone rubber films by Harris.(l) These forces are now measureable by two independant means.In the first of these assays, weakly crosslinked films are made, into which latex beads have been embedded.(Fig.2) These films report local cell-mediated traction forces as bead displacements in the plane of the film(Fig.3), which recover when the applied force is released. Calibrated flexible glass microneedles are then used to reproduce the translation of individual beads. We estimate the force required to distort these films to be 0.5 mdyne/μm of bead movement. Video-frame analysis of bead trajectories is providing data on the relative localisation, dissipation and kinetics of traction forces.


Author(s):  
Russalina Stroeder ◽  
Julia Radosa ◽  
Lea Clemens ◽  
Christoph Gerlinger ◽  
Gilda Schmidt ◽  
...  

Abstract Purpose To assess changes in the pelvic floor anatomy that cause pelvic floor disorders (PFDs) in primigravidae during and after pregnancy and to evaluate their impact on women’s quality of life (QoL). Methods POP-Q and translabial ultrasound examination was performed in the third trimester and 3 months after delivery in a cohort of primigravidae with singleton pregnancy delivering in a tertiary center. Results were analyzed regarding mode of delivery and other pre- and peripartal factors. Two individualized detailed questionnaires were distributed at 3 months and at 12 months after childbirth to determinate QoL. Results We recruited 45 women, of whom 17 delivered vaginally (VD), 11 received a vacuum extraction delivery (VE) and 17 a Cesarean section in labor (CS). When comparing third-trimester sonography to 3 months after delivery, bladder neck mobility increased significantly in each delivery group and hiatal area increased significantly in the VD group. A LAM avulsion was found in two women after VE. Connective tissue weakness (p = 0.0483) and fetal weight at birth (p = 0.0384) were identified as significant risk factors for the occurrence of PFDs in a multivariant regression analysis. Urinary incontinence was most common with 15% and 11% of cases at 3, respectively, 12 months after delivery. 42% of women reported discomfort during sexual intercourse, 3 months after delivery and 24% 12 months postpartum. Although 93% of women engage a midwife after delivery, only 56% participated in pelvic floor muscle training. Conclusion Connective tissue weakness and high fetal weight at birth are important risk factors for the occurrence of PFDs. Nevertheless, more parturients should participate in postpartal care services to prevent future PFDs.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jakub Mlodawski ◽  
Marta Mlodawska ◽  
Justyna Armanska ◽  
Grzegorz Swiercz ◽  
Stanisław Gluszek

AbstractInduction of labour (IOL) is increasingly used in obstetric practice. For patients with unfavourable cervix, we are constantly looking for an optimal, in terms of effectiveness and safety, ripening of cervix protocol. It was retrospective cohort study. We analyzed obstetrical results in 481 patients undergoing IOL in one center using two different vaginal inserts that release prostaglandins at a constant rate for 24 h—misoprostol vaginal insert (MVI) with 200 µg of misoprostol (n = 367) and dinoprostone vaginal insert (DVI) with 10 mg of dinoprostone (n = 114). Full-term, single pregnancy patients with intact fetal membranes and the cervix evaluated in Bishop score ≤ 6 were included in the analysis. In the group of MVI patients, the labour ended with caesarean section more often (OR 2.71 95% CI 1.63–4.47) and more frequent unreassuring cardiotocographic trace indicating the surgical delivery occurred (OR 2.38 95% CI 1.10–5.17). We did not notice any differences in the percentage of vacuum extraction and patients in whom the use of oxytocin was necessary during labour induction. The clinical status of newborns after birth and the pH of cord blood did not differ between groups.The use of MVI 200 μg in patients with an unriped cervix is associated with a greater chance of completing delivery by caesarean section and increased chance of abnormal intrapartum CTG trace compared to the use of DVI 10 mg. These differences do not affect the clinical and biochemical status of the newborn.


2012 ◽  
Vol 91 (12) ◽  
pp. 1453-1459 ◽  
Author(s):  
MATHILDE MAAGAARD ◽  
JEANETT OESTERGAARD ◽  
MARIANNE JOHANSEN ◽  
LISE LOTTE ANDERSEN ◽  
CHARLOTTE RINGSTED ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Johann Zwirner ◽  
Aqeeda Singh ◽  
Francesca Templer ◽  
Benjamin Ondruschka ◽  
Niels Hammer

AbstractIt is unclear whether plantar and posterior heel spurs are truly pathological findings and whether they are stimulated by traction or compression forces. Previous histological investigations focused on either one of the two spur locations, thereby potentially overlooking common features that refer to a uniform developmental mechanism. In this study, 19 feet from 16 cadavers were X-ray scanned to preselect calcanei with either plantar or posterior spurs. Subsequently, seven plantar and posterior spurs were histologically assessed. Five spur-free Achilles tendon and three plantar fascia entheses served as controls. Plantar spurs were located either intra- or supra-fascial whereas all Achilles spurs were intra-fascial. Both spur types consistently presented a trabecular architecture without a particular pattern, fibrocartilage at the tendinous entheses and the orientation of the spur tips was in line with the course of the attached soft tissues. Spurs of both entities revealed tapered areas close to their bases with bulky tips. Achilles and plantar heel spurs seem to be non-pathological calcaneal exostoses, which are likely results of traction forces. Both spur types revealed commonalities such as their trabecular architecture or the tip direction in relation to the attached soft tissues. Morphologically, heel spurs seem poorly adapted to compressive loads.


2009 ◽  
Vol 96 (2) ◽  
pp. 729-738 ◽  
Author(s):  
Christopher A. Lemmon ◽  
Christopher S. Chen ◽  
Lewis H. Romer

Sign in / Sign up

Export Citation Format

Share Document