Spelling suggestions: "subject:"soft tissue"" "subject:"oft tissue""
21 |
The effects of soft tissue massage pre and post cervical spine adjustment in cervical facet syndromeDe Lange, Emeyn Petro 07 June 2012 (has links)
M.Tech. / Purpose: The aim of this study was to evaluate the relative effectiveness of the application of soft tissue massage to the posterior neck muscles before, and after, chiropractic adjustment to the cervical spine in the treatment of cervical facet syndrome. To determine the most effective treatment protocol; the patient‟s perceptions and objective findings were used. These findings were assessed by completing a Visual Analogue Scale, a McGill Pain Questionnaire and a Vernon-Mior Neck Pain and Disability Index, and measuring the cervical spine range of motion using a Cervical Range of Motion goniometer. The questionnaires were completed and the ROM readings taken prior to treatment on the first, fourth and seventh visits. Method: Forty participants who met the inclusion criteria were randomly allocated to two different groups of twenty each. One group received soft tissue massage to the posterior neck musculature prior to the application of chiropractic adjustments to the subluxations of the cervical spine. The second group received the chiropractic adjustments to subluxations of the cervical spine that was followed by soft tissue massage to the posterior neck. Treatment took place over a period of three weeks, and participants were treated six times out of a total of seven visits. Procedure: Subjective data was collected at the first and fourth visit prior to treatment, as well as on the seventh visit by means of a Visual Analogue Scale (VAS), McGill Pain Questionnaire as well as a Vernon-Mior Neck Pain and Disability Index to assess pain and disability levels. Objective data was collected at the first and fourth visit prior to treatment, and at the seventh visit by means of a Cervical Range of Motion goniometer (C.R.O.M.). Data collected was analysed by STATCON. Results: Both groups improved well over time subjectively and objectively but none more superior. Statistically significant improvements in group 1 and group 2 were noted over the duration of the study with regards to pain, disability, and cervical spine range of motion.
|
22 |
Modelling Soft-Tissue Motion During Human Movement Experiments to Improve Calculations of Skeletal KinematicsBaklouti, Firas 26 May 2021 (has links)
In Canada, approximately 544,000 upper-limb injuries occurred in a 12-month period between 2009 and 2010, many of which were injuries to the rotator cuff muscles of the shoulder. Because of the complex structure and function of the shoulder, it is often difficult to determine which muscles have been injured. The most widely used technology to study human movement is motion capture, wherein markers are affixed to a subject’s skin and are tracked by cameras as the subject moves. The recorded marker trajectories are then used to estimate the bone locations and joint angles during the tracked motion. This is called an inverse kinematic simulation. The simulation can then be used to estimate variables that are difficult or impossible to measure directly, such as the activation of single muscle heads within a muscle group. However, muscles bulge and skin stretches during movement, so the markers that are affixed to the skin generally move relative to the underlying bones. These errors, known as soft-tissue artifacts, lead to uncertainty in the calculation of bone locations and, consequently, uncertainty in the computed skeletal joint angles. This uncertainty limits the use of inverse kinematic simulations in clinical settings. Given the skin tissue’s elastic behaviour, a spring-based equilibrium model can be used to estimate the behaviour of skin during non-impulsive motion. In the proposed model, markers were placed on the surface of ellipsoids (representing the thorax, abdomen, scapula, and upper arm) and were attached to each other via springs. The system was assumed to remain in static equilibrium during sufficiently slow movements to approximate the stretch of the skin. In this thesis, the development and application of a proof-of-concept model to estimate the pose of the skeleton is described. This work demonstrates the feasibility of using such a model to reduce errors due to soft-tissue motion.
|
23 |
3D soft tissue effects of rapid palatal expansionTorres, Diana M. 30 June 2019 (has links)
This retrospective cohort study investigated the effects of rapid maxillary expansion on the soft tissues using CBCTs. The sample consisted of 60 subjects: experimental group (n=30, treated with rapid maxillary expansion (RME), age:10.93 ± 2.20) and control group (n=30, age 11.43 ± 2.8). Soft tissue measurements were made using soft tissue landmarks. Paired t-test was used to compare the changes after expansion, and student t-test was used to compare the experimental and the control group. Intraclass correlation coefficient was used to evaluate intra-examiner reliability.
Statistically significant differences were noted when comparing the experimental to the control group in transverse and anterior posterior dimensions. Increase was noted at the bialar distance (0.90mm, p=0.0363), nostril medium left to midsagittal plane (0.75mm, p=0.0423), the angle of pronasale to nostril base right and left (1.640, p<.001), columella width (0.56mm, p=0.0272), nostril base left to midsagittal plane, (1.03mm, p=0.0207), chelion right to endocanthus right (1.57mm, p=0.0086), chelion left to endocanthus left (1.96mm, p=0.0015). Anteroposteriorly, the tip of the nose moved forward (pronasale to coronal plane (1.97mm, p=0.0018), nostril medium right to coronal plane (1.07mm, p=0.0486), alare right to coronal plane (1.67mm, p=0.0117), pronasale to nostril base left (2.24mm, p<0.001) and right (2.12mm, p<0.001).
Finally comparing genders, all the measurements were significantly greater in males compared to females except for columella width.
In conclusion, RME influences soft tissue changes of the face, specifically in the nasal area. The base of the nose, bialar distance and columella widened while the tip of the nose moved forward.
|
24 |
Multiscale Structure-Function Relations of a TendonWilliams, Lakiesha Nicole 09 December 2006 (has links)
In 1998, the United States National Committee on Biomechanics (USNCB) established an evolving discipline called Functional Tissue Engineering (FTE). In establishing this discipline, the goals of the USNCB were to advance FTE by increasing awareness among tissue engineers about the importance of restoring function when engineering tissue constructs. Another goal was to encourage tissue engineers to incorporate these functional criteria in the design, manufacturing and optimization of tissue engineered constructs. Based on this motivation, an investigation of the structure and mechanical properties of the rabbit patellar tendon will be executed, with the ultimate goal of creating a multiscale soft tissue model based on internal state variable (ISV) theory. Many continuum scale models, mostly phenomenological and microstrucutral, have been created to contribute to the understanding of the complex functional properties of the tendon, such as its anisotropy, inhomogeneity, nonlinearity, and viscoelasticity. However, none of these models have represented the mechanical behavior of the tendon in the presence of internal structural change on a multiscale level. The development of a multiscale ISV model will allow the capture of the irreversible, path history dependent aspects of the material behavior. The objective of this study is to contribute to the multiscale ISV model development by quantifying the structure- property relations. In particular, the fibril distribution at the microstructural level and the resultant multiaxial stress states (longitudinal and transverse compression and longitudinal tension) will be examined).
|
25 |
Experimental and Multiscale Computational Approaches to the Nonlinear Characterization of Liver TissueRoan, Esra 03 July 2007 (has links)
No description available.
|
26 |
Algorithms for Nonlinear Finite Element-based Modeling of Soft-tissue Deformation and CuttingGhali, Bassma 07 1900 (has links)
<p> Advances in robotics and information technology are leading to the development of virtual reality-based surgical simulators as an alternative to the conventional means of medical training. Modeling and simulation of medical procedures also have numerous applications in pre-operative and intra-operative surgical planning as well as robotic (semi)-autonomous execution of surgical tasks. </p> <p> Surgical simulation requires modeling of human soft-tissue organs. Soft-tissues
exhibit geometrical and material nonlinearities that should be taken into account for realistic modeling of the deformations and interaction forces between the surgical tool and tissues during medical procedures. However, most existing work in the literature, particularly for modeling of cutting, use linear deformation models. In this thesis, modeling of two common surgical tasks, i.e. palpation and cutting, using nonlinear modeling techniques has been studied. The complicated mechanical behavior of soft-tissue deformation is modeled by considering both geometrical and material nonlinearities. Large deformations are modeled by employing a nonlinear strain measure, the Green-Lagrange strain tensor, and a nonlinear stress-strain curve is employed by using an Ogden-based hyperelastic constitutive equation. The incompressible property of soft-tissue material during the deformation is enforced by modifying the strain energy function to include a term that penalizes changes in the object's area/volume. The problem of simulating the tool-tissue interactions using nonlinear dynamic analysis is formulated within a total Lagrangian framework. The finite element method is utilized to discretize the deformable object model in space and an explicit time integration is employed to solve for the resulting deformations. </p> <p> In this thesis, the nonlinear finite element analysis with the Ogden-based constitutive equation has also been applied to the modeling of soft-tissue cutting. Element separation and node snapping are used to create a cut in the mesh that is
close to the tool trajectory. The external force applied on the object along the tool direction is used as a physical cutting criterion. The possibility of producing degenerated elements by node snapping that can cause numerical instability in the simulation is eliminated by remeshing the local elements when badly shaped elements are generated. The remeshing process involves retriangulation of the local elements using the Delaunay function and/ or moving a node depending on what is needed in order to generate elements with the required quality. </p> <p> Extensive simulations have been carried out in order to evaluate and demonstrate the effectiveness of the proposed modeling techniques and the results are reported in the thesis. A two-dimensional object with a concentrated external force has been considered in the simulations. </p> / Thesis / Master of Applied Science (MASc)
|
27 |
Functional and Morphological Characteristics of Smooth Muscle in the Rat VaginaHuntington, Alyssa Joan 15 June 2021 (has links)
The vagina is an essential organ of the female reproductive system that has been largely understudied in the field of biomechanics. The ability of the vagina to contract gives rise to a set of active mechanical properties that contribute to the complex function of this organ in-vivo. After briefly reviewing experimental studies on the active properties of the vagina, including the differences in contractility with respect to anatomic regions and orientations, neural pathways, life events, pelvic floor disorders, and surgical mesh treatment, we present our novel experimental studies that aim toward filling existing knowledge gaps on vaginal tissue morphology and contractile function of the vagina. First, we quantified the large heterogeneous deformations that the vagina experiences during contractions for the first time. For this study, vaginal specimens were subjected to isometric planar biaxial tests, during which they were induced to contract via KCl at four applied equi-biaxial stretches. The digital image correlation method was used to perform full-field strain analysis during each contraction. The vagina was found to have anisotropic contractile behavior, generating higher forces and experiencing higher magnitude strains along the longitudinal direction (LD) than along the circumferential direction (CD) during contractions. Then, we performed the first detailed quantification of the distribution and alignment of vaginal smooth muscle and nerves throughout the vagina. Toward this goal, vaginas from adult female rats were subjected to a tissue clearing and immunohistochemistry protocol. Tissue clearing increased the transparency of the specimens such that organs could be imaged without sectioning, thus preserving the 3D architecture of the tissue. This analysis revealed a bimodal distribution of muscle alignment angles, with a significantly higher proportion of muscle oriented along the LD than along the CD of the organ. The morphologic and functional properties of the smooth muscle within the healthy vagina need to be fully investigated so that detrimental alterations in vaginal contractility, such as those caused by pelvic floor disorders and current treatment strategies, can be prevented. / Doctor of Philosophy / The vagina is an essential organ of the female reproductive system that has been largely understudied in the field of biomechanics. The ability of the vagina to contract gives rise to a set of active mechanical properties that contribute to the complex function of this organ in-vivo. After briefly reviewing experimental studies on the active properties of the vagina, including the differences in contractility with respect to anatomic regions and orientations, neural pathways, life events, pelvic floor disorders, and surgical mesh treatment, we present our novel experimental studies that aim toward filling existing knowledge gaps on vaginal tissue morphology and contractile function of the vagina. First, we quantified the large heterogeneous deformations that the vagina experiences during contractions for the first time. For this study, vaginal specimens were subjected to isometric planar biaxial tests, during which they were induced to contract via KCl at four applied equi-biaxial stretches. The digital image correlation method was used to perform full-field strain analysis during each contraction. The vagina was found to have anisotropic contractile behavior, generating higher forces and experiencing higher magnitude strains along the longitudinal direction (LD) than along the circumferential direction (CD) during contractions. Then, we performed the first detailed quantification of the distribution and alignment of vaginal smooth muscle and nerves throughout the vagina. Toward this goal, vaginas from adult female rats were subjected to a tissue clearing and immunohistochemistry protocol. Tissue clearing increased the transparency of the specimens such that organs could be imaged without sectioning, thus preserving the 3D architecture of the tissue. This analysis revealed a bimodal distribution of muscle alignment angles, with a significantly higher proportion of muscle oriented along the LD than along the CD of the organ. The morphologic and functional properties of the smooth muscle within the healthy vagina need to be fully investigated so that detrimental alterations in vaginal contractility, such as those caused by pelvic floor disorders and current treatment strategies, can be prevented.
|
28 |
On the behaviour of porcine adipose and skeletal muscle tissues under shock compressionWilgeroth, J. M. January 2014 (has links)
The response of porcine adipose and skeletal muscle tissues to shock compression has been investigated using the plate-impact technique in conjunction with manganin foil pressure gauge diagnostics. This approach has allowed for measurement of the levels of uniaxial stress imparted to both skeletal muscle and rendered adipose tissue by the shock. In addition, the lateral stress component generated within adipose tissue during shock loading has also been investigated. The techniques employed in this study have allowed for equation-of-state relationships to be established for the investigated materials, highlighting non-hydrodynamic behaviour in each type of tissue over the range of investigated impact conditions. While the adipose tissue selected in this work has been shown to strengthen with impact stress in a manner similar to that seen to occur in polymeric materials, the skeletal muscle tissues exhibited a ow strength, or resistance to compression, that was independent of impact stress. Both the response of the adipose material and tested skeletal muscle tissues lie in contrast with the shock response of ballistic gelatin, which has previously been shown to exhibit hydrodynamic behaviour under equivalent loading conditions. Plate-impact experiments have also been used to investigate the shock response of a homogenized variant of one of the investigated muscle tissues. In the homogenized samples, the natural structure of skeletal muscle tissue, i.e. a fibrous and anisotropic composite, was heavily disrupted and the resulting material was milled into a fine paste. Rather than matching the response of the unaltered tissues, the datapoints generated from this type of experiment were seen to collapse back on to the hydrodynamic response predicted for skeletal muscle by its linear equation-of-state (Us = 1.72 + 1.88up). This suggests that the resistance to compression apparent in the data obtained for the virgin tissues was a direct result of the interaction of the shock with the quasi-organized structure of skeletal muscle. A soft-capture system has been developed in order to facilitate post-shock analysis of skeletal muscle tissue and to ascertain the effects of shock loading upon the structure of the material. The system was designed to deliver a one-dimensional, at-topped shock pulse to the sample prior to release. The overall design of the system was aided by use of the non-linear and explicit hydrocode ANSYSR AUTODYN. Following shock compression, sections of tissue were imaged using a transmission electron microscope (TEM). Both an auxetic-like response and large-scale disruption to the I-band/Z-disk regions within the tissue's structure were observed. Notably, these mechanisms have been noted to occur as a result of hydrostatic compression of skeletal muscle within the literature.
|
29 |
Imaging of soft tissue tumors /Hildur Einarsdóttir, January 2003 (has links)
Diss. Stockholm : Karol. inst., 2003.
|
30 |
Performance of a cadmium tungstate MVCT scannerKirvan, Paul Francis. January 2010 (has links)
Thesis (M.Sc.)--University of Alberta, 2010. / A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Medical Physics, Department of Physics. Title from pdf file main screen (viewed on July 17, 2010). Includes bibliographical references.
|
Page generated in 0.0517 seconds