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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Lumbar MRI abnormalities and muscle morphology, trunk kinematics and lower back injury in professional fast bowlers in cricket

Ranson, Craig A January 2007 (has links)
Lower back injury remains the most important injury problem in professional cricket with lumbar stress fractures in fast bowlers accounting for the most lost playing time. Previous research has associated workload, paraspinal muscle asymmetry and technique factors with lower back injury in fast bowlers, however, preventative strategies such as workload directives and coaching guidelines have not reduced the incidence and prevalence of these injuries. Recent developments in medical imaging technology have improved diagnosis of pathologies such as lumbar posterior bony element (partes interarticulares and pedicles) stress fractures and intervertebral disc degeneration in athletes whilst also allowing quantification of other, potentially associated factors such as paraspinal muscle asymmetry. However, there is very little published research regarding the use of modalities such as magnetic resonance imaging (MRI) in the identification and prognosis of these types of injuries in fast bowlers. Similarly, advances in three-dimensional (3D) motion analysis has aided technique evaluation in a variety of sports, however, little remains known about the pathomechanics of lower back injury in fast bowling. Therefore, the aim of this doctoral research was to investigate relationships between lower back injury and; the MRI appearance of the lumbar posterior bony elements and intervertebral discs, MRI-derived lumbar muscle morphology and the three-dimensional (3D) trunk kinematics of professional fast bowlers in cricket. This was examined in a series of five studies. The first study undertaken was an investigation of the MRI appearance of the lumbar spines of 36 asymptomatic professional fast bowlers and 17 active controls. / It was identified that the fast bowlers had a high prevalence of multi-level, predominantly non-dominant side, acute and chronic stress changes in the posterior bony elements of the lumbar spine. Multiple level disc degeneration was also more advanced in the fast bowlers compared with the control - iv - participants. However, disc degeneration appeared not to be associated with lumbar stress injury. The second study investigated the reliability and accuracy of using MRI to determine the FCSA of the lumbar paraspinal muscles (psoas, quadratus lumborum, erector spinae and multifidus). The novel methodology developed in this study was determined to be both valid and highly reliable. In the third study, this technique was then used to describe the functional crosssectional area (FCSA) morphology of the paraspinal muscles in a group of 46 professional fast bowlers and the 17 control participants scanned in the first study. It reinforced that there was a higher prevalence of lumbar muscle asymmetry in the fast bowler group. Paraspinal muscle asymmetry, consistent with hypertrophy of the dominant side muscle, was most prevalent in the quadratus lumborum of fast bowlers, and was also evident in the lumbar multifidus in both groups of subjects. The aims of the fourth study of the thesis were to quantify the proportion of lower trunk motion utilised during the delivery stride of fast bowling and to investigate the relationship between the most accepted fast bowling action classification system and potentially injurious kinematics of the lower trunk. 3D kinematic data were collected from 50 male professional fast bowlers during fast bowling trials and these were normalised to each bowler’s standing lower trunk range of motion. A high percentage of the fast bowlers used a mixed bowling action attributable to having shoulder counter-rotation greater than 30°. / The greatest proportion of lower trunk extension (26%), contralateral side-flexion (129%) and ipsilateral rotation (79%) was utilised during the front foot contact phase of the fast bowling delivery stride. There was no significant difference between mixed and non-mixed bowlers in the range of motion used during fast bowling. It was concluded that fast bowling action characteristics currently used to identify potentially dangerous action types may not be directly related to the likely pathomechanics of contralateral side lumbar stress injuries. It is proposed that coupled lower trunk extension, ipsilateral rotation in addition to extreme contralateral side-flexion, during the early part of the front foot contact phase of the bowling action may be an important mechanical factor in the aetiology of this type of injury. In the final study, a combination of the factors described in earlier studies i.e. the lumbar MRI appearance of the partes interarticulares and intervertebral discs, paraspinal muscle asymmetry and selected bowling action and delivery stride trunk kinematic variables, were examined. Therefore, the aim of this study was to examine the relationship between fast bowler lower back injury occurrence (one season either side of testing) and the aforementioned factors that were measured when participants were asymptomatic and bowling competitively. The results of this study indicated that a high percentage of professional fast bowlers in the United Kingdom continue to sustain a high number of acute lumbar stress injuries and these result a significant amount of lost playing and training time. Fast bowling action classification and lower trunk kinematic variables were not conclusively linked to acute lumbar stress injury occurrence. However, further investigation of the effect of coupled lower trunk motion on nondominant side lumbar bone stress is indicated. / The presence of acute MRI stress changes (particularly acute stress changes such as bone marrow oedema, periostitis and acute fracture lines) in the non-dominant side lumbar posterior elements seem to have a relationship with acute stress injury occurrence. Regular lumbar MRI scanning may assist in identifying early acute stress changes prior to the onset of symptoms. Intervertebral disc degeneration was less prevalent amongst professional fast bowlers who suffered acute stress injuries than those who had no significant lower back injury. Finally, although fast bowlers have a high prevalence of quadratus lumborum and lumbar multifidus asymmetry (larger on the dominant side), there was no observed relationship between acute lumbar stress injury and these findings.
12

The transmission of vibration at the lower lumbar spine due to whole-body vibration: a numerical human model study

Pang, Toh Yen, tohyen_pang@yahoo.com January 2006 (has links)
Lower back disorders due to whole-body vibration (WBV) are the most common injuries reported by professional drivers. Such injuries often have long-term complications leading to significant personal and societal costs. An improved mathematical model of the whole human body would contribute to a better understanding of the mechanisms of lower back injury and be valuable in injury prevention research. Current biodynamic human models reported in the literature lack detailed information for predicting the non-linearity due to vibration amplitude of transmission of vibration from seat to a human. Therefore, one of the primary objectives of this research has been to develop and validate a detailed threedimensional biodynamic human model, with special attention given to the incorporation of active trunk muscles with non-linear stiffness properties. These muscles have been incorporated into an existing spine and neck model of a MADYMO 50th percentile male occupant model. A detailed multi-body human model has been developed, called MODEL ONE. This thesis shows that incorporating non-linear stiffness functions and energy dissipation using hysteresis or damping into a human model is appropriate for predicting non-linear biodynamic responses in arbitrary excitation functions. A major advantage of MODEL ONE compared to other multi-body models and lumped mass models is its ability to predict nonlinear seat-to-human transmissibility. However MADYMO 50th male occupant models use simplified geometry and rigid bodies to represent the lower lumbar spine. These simplified spinal models have no ability to simulate the internal stresses and deformations of soft tissues, even if these are the apparent cause of lower back pain (LBP). Therefore a detailed finite element human lower lumbar spine model - with appropriate material properties and capable of simulating internal stresses⎯is necessary, in order to better understand spinal injuries under WBV. A three-dimensional finite element model of a lower lumbar spine motion segment - called MODEL TWO - has thus been developed for the present study. MODEL TWO comprises a detailed geometric description of vertebrae, nucleus pulposus, endplates, and intervertebral discs. The intervertebral discs lump together the annulus fibrosus, ground substance and ligaments. The vertebrae have been assumed to be rigid. The material properties of the intervertebral discs of MODEL TWO were obtained from test matrices and from various parameter data reported in the literature. MODEL TWO has been validated against cadaveric experiments reported in the literature. The mechanical behaviour and stress distribution within the MODEL TWO intervertebral disc agree reasonably well with the cadaveric experiments. MODEL TWO was integrated into MODEL ONE to form a new human model, called MODEL THREE, which was subsequently dynamically validated against volunteers� responses to WBV reported in the literature. MODEL THREE, as presented in this thesis, consists of a multi-body human model with detailed representation of a finite element (FE) lower lumbar spine. As far as the author is aware, MODEL THREE is the first model with detailed representation of a FE lower lumbar spine to successfully demonstrate that it is capable of simulating the stress profile of the entire intervertebral disc and endplate region due to WBV. The simulated results revealed abnormal stress concentrations in both the posterior and xviii the posterolateral annulus. The stresses increased most in the posterolateral intervertebral discs region during WBV, suggesting a possible mechanism for disc mechanical overload leading to fatigue fracture and degeneration. The results from MODEL THREE are promising and lead to a more comprehensive understanding of the behaviour of the intervertebral disc under WBV. MODEL THREE has also provided a good foundation for the development of a bio-fidelity human model. However, implementation of currently unavailable and/or inadequate in vitro and in vivo experimental studies is needed to further validate and develop MODEL THREE. A better understanding of injury mechanisms and the clinical significance of LBP will ultimately be arrived at using a combination of analytical models with in vitro and in vivo experimental data.
13

Minkštojo įtvaro poveikis nėščiųjų juosmeninės stuburo dalies skausmui: atvejų analizė / Kinesiotaping influence on low back pain in pregnant women: cases study

Pūraitė, Rūta 10 September 2013 (has links)
Vis dažniau yra diskutuojama apie minkštojo įtvaro poveikį nėščiųjų juosmeninės stuburo dalies skausmo mažinimui. Yra skausmo sindromų, būdingų tik moterims. Vienas jų – nėščiųjų juosmens skausmas. Apie 50–80 proc. nėščiųjų vargina juosmens skausmai, kurie dažniausiai prasideda 5–7 nėštumo mėnesį, tačiau skausmai gali prasidėti 8—12 nėštumo savaitę (Samėnienė, 2005). Tikslas. Nustatyti minkštojo įtvaro poveikį nėščiosioms mažinant juosmeninės stuburo dalies skausmą. Objektas. Minkštojo įtvaro poveikis mažinant nėščiųjų juosmeninės stuburo dalies skausmui. Hipotezė. Manome, kad minkštasis įtvaras turės teigiamą poveikį nėščiosioms mažinant juosmeninės stuburo dalies skausmą, kadangi minkštojo įtvaro dėka yra suteikiama atrama ir stabilumas sąnariams ir raumenims netrikdant jų kraujotakos ir nevaržant judesių. Tyrimo metu buvo spėjama, kad minkštasis įtvaras turės teigiamą poveikį nėščiosioms mažinant juosmeninės stuburo dalies skausmą Tyrimo uždaviniai: 1. Įvertinti nėščiųjų juosmeninės stuburo dalies skausmą ir negalią prieš minkštojo įtvaro taikymą ir po. 2. Įvertinti kaip minkštojo įtvaro poveikis turi įtakos gyvenimo kokybei prieš ir po minkštojo įtvaro taikymo. 3. Įvertinti nėščiųjų judesių baimę (kinezifobiją) prieš ir po minkštojo įtvaro taikymo. Tyrimas buvo atliekamas Lietuvos Sporto Universiteto kineziterapijos salytėje. Tyrime iš viso dalyvavo septynios niekada stuburo skausmų neturėjusios nėščiosios. Atliekant tyrimą buvo vertinama nėščiųjų nugaros skausmas... [toliau žr. visą tekstą] / Increasingly there are arguable about kinesiotaping influence pregnant women low back pain reduction. There are pain syndromes appropriate just for women. First – pregnant low back pain. About 50—80  pregnant women suffers from low back pain, which normally begins in the 5-7 pregnancy month, however it can start and 8-12 week of pregnant (Samėnienė, 2005). That study main aim was to determine kinesiotaping influence for pregnant women low back pain reduction. Study object was kinesiotaping influence for pregnant women low back pain. Stydy hypothesis: kinesiotaping will have positive effect for preganant women low back pain reduction. Study tasks were: 1. To assess pregnant women low back pain and disability before and after kinesiotaping. 2. To assess pregnant women low back pain influence for living quality before and after kinesiotaping. 3. To assess pregnant women fear of movements (kinesiophobia) before and after kinesiotaping. Study was performed in Lithunians Sports University‘s physical therapy room. In the study participated seven pregnant women who have never suffered from low back pain. In the study were assessed pregnant women low back pain, influence for quality of living, fear of movements. After kinesiotaping investigative‘s pain decreased significantly (p<0,05). Pain influence for quality of living statsitically reliable diffrence were not found (p>0,05). Fear of movements statistically signficant improve (p<0,05). Kinesiotaping the biggest influence had for... [to full text]
14

Back Muscle Endurance as Measure by Ito Test Duration

Figueredo, Ronald 24 March 2017 (has links)
Lower back pain remains one of the most common problems in public health throughout the industrialized world (Strine and Hootman) (Shiri, Solovieva and K.). The prevalence is about 39-54% annually and 60-65% in a lifetime (Hillman, Wright and Rajaranam) (Leboeuf-Yde, N. and Lauritzen). In the United States, lower back pain is the second most common cause of disability, and is the highest cause of disability among men (Center for Disease Control, 2009). An individual quantitative physical examination to detect muscle deficiencies would be very useful for proper placement of workers in demanding physical jobs where back injuries are common. Trunk muscle extensor endurance might be the best approach for this issue.
15

Two- And Three-Plane Job Risk Classification Using Motion Capture: An Examination Of The Marras Et Al. Model, 1993

Cappelli, Tara Marie 10 December 2005 (has links)
Lower Back Disorders account for 16-19% of work related claims and 33-41% of dollars paid in workers? compensation (as cited in Marras, 1999), with impacts to society approaching $100 billion dollars annually (as cited in Marras et al., 1999). Dr. William Marras engineered a device to track trunk kinematics in order to develop a Job Risk Classification Model for predicting high-risk group probability of lower back injury. The device has been validated, but other technologies such as 3-D motion capture can potentially gather the same data. This study examined the use of motion capture to apply two- and three-plane lifting tasks to the Marras model and compare results with commonly used assessment techniques. Regardless of the fact that the Marras model results were drastically different from NIOSH and RULA, motion capture was able to gather all necessary data for running the models and has a promising future in ergonomic assessments.
16

EFFECT OF FORKLIFT OPERATION ON LOWER BACK PAIN - AN EVIDENCE-BASED APPROACH

BARRIERA VIRUET, HERIBERTO 21 July 2006 (has links)
No description available.
17

Polymer Composite Spinal Disc Implants

Frost, Brody A. January 2017 (has links)
The goal of this research study was to create an artificial annulus fibrosus similar to that of the natural intervertebral disc, as well as find preliminary results for vertebral endplate connection and nucleus pulposus internal pressure, for the correction of disc degeneration in the spine. The three-part composite samples needed to demonstrate good shock absorption and load distribution while maintaining strength and flexibility, and removing the need for metal in the body, something of which no current total disc replacement or spinal fusion surgery can offer. For this study, the spinal disc was separated into its three different components, the annulus fibrosus, the nucleus pulposus, and the vertebral endplates, each playing a vital role in the function of the disc. Two low-cost materials were selected, a Covestro polyurethane and cellulose nanocrystals, for the purpose of creating a polymer composite spinal disc implant. A methodology was established for creating the cast composite material for use as an annulus fibrosus, while also investigating its mechanical properties. The same composite material was used to acquire preliminary results for vertebral endplate connection to the synthesized annulus, however no additional material was used to determine or mimic the mechanical properties of these endplates, due to time constraints. Also because of time constraints, the nucleus used in this study was only comprised of water with no other additives for preliminary testing since the natural nucleus is comprised of about 80-90% water. These properties were then compared to the mechanical properties of the natural disc, so that they could be finely tuned to emulate the natural disc. It is shown in this study that the composite material, when swelled in water, was able to mimic the annulus fibrosus in tensile strength and modulus, however showed higher compressive strength and modulus than ideal. The samples also did not undergo any permanent deformation within the realm of force actually introduced to the natural disc. The vertebral endplates showed decent adhesion to the synthesized annulus, however there were slight defects that became failure concentrators during compression testing. The nucleus showed promising results maintaining good internal pressure to the system causing better compressive load distribution, with barreling of the samples. / Master of Science / Spinal disc degeneration is a very prevalent problem in today’s society, effecting anywhere from 12% to 35% of a given population. It usually occurs in the lumbar section of the spine, and when severe enough, can cause bulging and herniation of the intervertebral disc itself. This can cause immense lower back pain in individual’s stricken with this disease, and in the US, medical costs associated with lower back pain to exceed $100 billion. Current solutions to this problem include multiple different treatment options of which, spinal fusion surgery and total disc replacement (TDR) are among the most common. Although these treatments cause pain relief for the majority of patients, there are multiple challenges that come with these options. For example, spinal fusion surgery severely limits the mobility of its patients by fusing two vertebrae together, disallowing any individual movement, and TDR can cause hypermobility in among the vertebrae and offer little to no shock absorption of loads. Therefore, a better treatment option is needed to relieve the pain of the patients, as well as maintain equal motion, shock absorption, and load cushioning to that of the normal intervertebral disc and remaining biocompatible. The goal of this research study was to create a three-component system, like that of the natural intervertebral disc, for the use of spinal disc replacement and to replace current options. The fabricated system was comprised of the three components found in the natural intervertebral disc; the annulus fibrosus, the nucleus pulposus, and the vertebral endplates. Because the system will need to go in-body, the materials used were all characterized as biocompatible materials; the polyurethane currently being used in medical devices and implants, and the cellulose nanocrystals (CNCs) coming from natural cellulose in sources such as wood and plants. The results determined that the mechanical properties of the system can be fine-tuned in order to mimic the natural strength and cushioning capabilities of the natural disc, based on CNC content added to the polyurethane, and when all three components of the system are added together, the compressive stress-strain is most similar to the natural disc in compression. However, the system did show failure in the connection between the annulus fibrosus and vertebral endplates, causing herniation of the nucleus similar to the initial problem attempting to be solved. For this, more ideal fabrication methods should be researched in the future including 3D printing techniques, injection molding, and roll milling. As well as alternate fabrication techniques, cell grow and viability should be determined to show that cells don’t die once the system in implanted.
18

Development of an individualized rowing seat for para-rowers

Dahlquist, Ludvig January 2024 (has links)
Background: Rowing is a demanding sport where extreme positions and high physical loads are obtained. This leads to injury risks, especially in the lower back. Another issue relates to comfortability. When rowing, the buttocks are the pivot point, and lots of pressure is placed on the sitting bones and surrounding tissues. For para-rowers, these issues can be even more prominent and important to consider. Purpose and aim: The purpose of this project was to develop a solution that enhances the enjoyment and comfortability for para-rowers. To do that, this project aimed to develop an individualized add-on product for rowing seats, with an included method to translate individual measurements into the design. Method: The Double Diamond Model was used to guide the project, where both qualitative and quantitative methods were included to reach the aim and purpose. To discover and define the problem, data was collected with literature review, benchmarking, and semi-structured interviews. With that data as a base, concepts were developed and selected, and the selected concept was tested with regards to pressure distribution. Results: The final concept was based on one individual and includes a seating area that has the exact shape of that individual. It does also include an increased back support and sideways support. To get measurements to design the individualized seat, a method consisting of scanning a vacuum pillow was used. Conclusion: The findings indicate that a perfectly fitted seat will spread out pressure more evenly around the buttocks, which enhances comfortability. There is, though, still much to consider and evaluate before this product can reach the market.
19

Alterations in Active and Passive Behavior of Lower Back Tissues Following Six Sessions of High Velocity Low Amplitude Spinal Manipulative Therapy for Healthy Participants

Croft, Emily C. 01 January 2016 (has links)
Non-specific low back pain (LBP) is a major health problem affecting a substantial portion of the population. The current treatments offered for non-specific LBP are oftentimes unsuccessful because the acting mechanism(s) of most treatment options are unknown. Obtaining a better understanding about the acting mechanism behind existing treatment options is, therefore, essential for the improvement of non-specific LBP treatment and management. The objective of this study was to gain a more comprehensive understanding about the acting mechanism of high velocity low amplitude spinal manipulative therapy, specifically the impact that high velocity low amplitude spinal manipulative therapy may have on the active and passive spinal musculoskeletal stabilizing subsystems along with the resultant spinal stability for healthy participants. A pre-post intervention study design completed by six healthy participants was used to quantify changes in the above noted aspects of spinal stability using a series of tests performed both before and after six sessions of high velocity low amplitude spinal manipulative therapy. The tests included seated balancing tests, lower back range of motion tests, and stress relaxation test. The six sessions of high velocity low amplitude spinal manipulative therapy did not significantly affect any of the test measurements among our healthy participant group.
20

Acupuncture for Quality of Life in Patients Having Pain Associated with the Spine: a Systematic Review

Lu, Shao-chen, ILLEGIBLE January 2008 (has links)
Background: Pain associated with the spine (PAWS) refers to pain in the neck, thorax, lower back or sacrum. It impacts on patients' Quality of Life (QoL), including working ability, daily functioning, sleep and psychological well-being. A number of clinical trials have demonstrated that acupuncture was beneficial for patients with PAWS. However the overall effect of acupuncture on these patients' QoL is unknown. Aims: The current study aimed to conduct a systematic review (SR) of clinical trials to determine the effect of acupuncture on QoL and pain for patients with PAWS. In addition, a narrative review (NR) was conducted to compare patients' perceived changes (PCC) with the standard QoL instruments used in acupuncture clinical trials for pain. Methods: For the SR, PubMed, Embase (via ScienceDirect), CINAHL (Via EBSCO) and Cochrane Central Register of Controlled Trials were searched. Randomised controlled trials (RCTs) of acupuncture for PAWS condition(s) that include both QoL and pain assessments with a Jadad score of three or greater were included. For the NR, PubMed was searched to identify studies reporting PPC after acupuncture and/or traditional Chinese medicine. Extracted data were grouped and compared with domains of the QoL instruments. Results: In total, 21 RCTs were included and 17 of them had sufficient data for analysis. QoL was measured using 15 different instruments. Randomisation procedures and dropouts were adequately reported in all 17 studies. Four studies compared acupuncture with wait-list or usual-care. Two demonstrated that acupuncture had a superior effect on improving physical and mental components of QoL measured by Short Form-36 health survey questionnaire and pain at the three month follow-up. Studies comparing acupuncture with sham/placebo acupuncture or placebo-TENS found either no difference between the treatments or conflicting results. When acupuncture was compared with active interventions, there was no difference except that at the intermediate-term follow-up massage was better for disability and pain and physiotherapy was better for Northwick Park Neck Pain Questionnaire. Acupuncture was also better than TENS for pain. The combined therapy of acupuncture and an active intervention showed a superior result than the latter alone in the short-term. Six studies were identified for the NR. Patients reported 11 categories of changes after acupuncture, such as reduced reliance on other therapies, enhanced spirituality, prevention of disease. However, these clinical outcomes were not included in any of the QoL instruments used in the included RCTs. Conclusion: There is moderate to strong evidence that acupuncture is more effective than wait-list or usual-care at the short-term follow-up in improving QoL of patients with PAWS. When acupuncture is combined with another therapy, the combined therapy seems to produce a better outcome. Acupuncture is not better than sham/placebo acupuncture or placebo-TENS. Surprisingly, the commonly used QoL instruments do not measure all the changes perceived by patients as a result of acupuncture and/or traditional Chinese medicine. There is a pressing need to design QoL assessments that are suitable for acupuncture research. Further studies should have larger sample sizes and additional validated outcome assessments are required to detect effects of acupuncture.

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