To see the other types of publications on this topic, follow the link: Biomechanical comparison.
Dissertations / Theses on the topic 'Biomechanical comparison'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Biomechanical comparison.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Wong, Peter. "Biomechanical comparison of lumbar disc replacements." View the abstract Download the full-text PDF version, 2009. http://etd.utmem.edu/ABSTRACTS/2009-014-Wong-index.htm.
Full textAbstract:
Thesis (M.S.)--University of Tennessee Health Science Center, 2009.Title from title page screen (viewed on October 8, 2009). Research advisor: Denis DiAngelo, Ph.D. Document formatted into pages (viii, 75 p. : ill.). Vita. Abstract. Includes bibliographical references (p. 34-38).
2
Post, Andrew. "Biomechanical comparison of stair and ramp descent." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27167.
Full textAbstract:
The purpose of this project was to quantify and analyze the changes that occur to the moments of force and moment powers at the joints of the lower extremity during stair and ramp descent. Methods. A sample population of five male and five female volunteers were asked to walk five times down a 10-degree ramp at normal gait speed, followed by five stair descent trials. Results and discussion. Stair descent has a larger eccentric plantar flexor peak at the ankle joint during weight acceptance. The knee exhibits slightly larger eccentric knee extensor peaks during ramp descent at push - off and there was higher loading of the hip during ramp descent as compared with stair descent. The higher ankle powers at FS during stair descent reveal a concern for those people suffering from ankle pathology and the larger hip and knee peaks during ramp descent is of concern to those with hip and knee problems. These results could be used in the rehabilitative considerations of patients with hip, knee and ankle replacements and as a baseline for future research. (Abstract shortened by UMI.)
3
Tsantrizos, Anthony. "Biomechanical comparison of anterior lumbar interbody fusion devices." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ37173.pdf.
Full text
4
Kaufmann, Alan. "Biomechanical Comparison of Meniscal Repair Systems in Shear Loading." Master's thesis, Temple University Libraries, 2013. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/216549.
Full textAbstract:
BioengineeringM.S.
A meniscal tear is an injury that often occurs as a result of a varus or valgus rotation of the femur on the tibia coupled with axial rotation while the knee is partially flexed, thus creating preferential loading of the posterior horn and shear forces on the meniscus. Such injuries can be repaired surgically, either with standard suturing techniques or with commercially available all-inside meniscal repair devices, which are designed to make the repair surgery faster, easier, and potentially safer. Many prior biomechanical studies have loaded an excised, repaired meniscus in tension and found that the repaired meniscus performs similarly to an uninjured sample. However, it is more appropriate to apply shear forces to the tissue in order to simulate the mechanism of injury. To date, three prior studies have investigated the biomechanical properties of meniscal repairs in shear, all of which used isolated meniscal tissue samples. The present study used an in situ bovine model to investigate the strength of commercially available meniscal repair systems under a shear loading regime. Medial menisci were torn and subsequently repaired using one of three techniques: standard inside-out vertical mattress sutures, Depuy Mitek Omnispan, or Smith & Nephew Fast-Fix. A control group was left unrepaired. Samples were subjected to a battery of cyclic side loading to create shear forces within the knee. Statistical analysis (ANOVA) demonstrated no significant difference in the stiffness, shear force, or subsidence between groups. The conclusion that the repair techniques perform similarly is consistent with tensile and in situ testing. Pathological observations showed no significant differences between repair devices, but all repaired samples demonstrated less wear than unrepaired samples, indicating that the experimental model is an effective method for creating wear within the knee. This result indicates that the flexible all-inside devices are mechanically comparable to the more commonly performed conventional suturing techniques. It is concluded that the mechanical performance may not be the best indicator of success of the surgical repair, as long as the device is able to anatomically reduce the tear.
Temple University--Theses
5
Ita, Meagan Eleanor. "Comparison of Q3s Anthropomorphic Test Device Biomechanical Responses to Pediatric Volunteers." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397486884.
Full text
6
McInnes, Kurtis Anthony. "Biomechanical comparison of two total ankle replacement designs : micromotion and kinematic patterns." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42747.
Full textAbstract:
Introduction: Arthritis is a degenerative disease that causes irreversible damage to a joint’s articular cartilage. Despite having high failure rates in early total ankle arthroplasty (TAA) models, recent improvements have increased the success of this procedure, providing end-stage ankle arthritis patients a viable alternative to fusion with better functional outcomes. Currently, the most prevalent cause of failure is aseptic loosening, which is believed to be affected by motion at the bone-implant interface. The objective of this study was to compare micromotion and kinematic patterns of two TAA designs.
Methods: A mechanical simulator was designed to apply compressive loads and bending moments to human cadaveric ankles, intact and replaced. It induced a maximal range of motion in the ankle about 3 orthogonal axes: plantarflexion-dorsiflexion (PF-DF), inversion-eversion (INV-EV), and internal-external rotation (IR-ER). Six ankle pairs were tested and compared. The implants analyzed were the Agility™ and the Scandinavian Total Ankle Replacement (S.T.A.R.®). Using an optical motion capture system, tibiocalcaneal kinematics and the relative bone-implant motion for each implant were recorded and analyzed.
Results: The Agility exhibited a greater amount of micromotion between the bone and prosthesis than the STAR for the tibial component in INV-EV (p=0.037), and for the talar component in PF-DF (p=0.002) and IR-ER (p=0.038). Micromotion magnitudes were affected by loading direction and compression. Kinematic changes were observed following replacement of the ankle joint. There were decreases in the amount of motion coupling for both implants when loaded in INV-EV and IR-ER. There were increases in joint translation for both implants in the medial/lateral direction under INV-EV loading, and for the STAR in the anterior/posterior and compression/distraction directions under PF-DF loading. No significant ROM differences were found.
Discussion: Increased micromotion in the Agility supports the hypothesis that higher aseptic loosening rates are correlated with reduced initial post-op fixation. The effect of loading direction on micromotion magnitude confirms the need to apply a variety of loading conditions to obtain a comprehensive micromotion analysis. Kinematic differences between implanted and intact ankles show that there is still room for improvement towards an ankle replacement design that replicates the performance of a healthy ankle.
7
Pugh, Gary Michael. "A biomechanical comparison of the front and rear lat pull-down exercise." [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0000772.
Full text
8
Miller, Laura. "Biomechanical comparison of different types of pitches in high school softball pitchers." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 115 p, 2008. http://proquest.umi.com/pqdweb?did=1619620651&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Full text
9
Dupuis, Christine Angela. "A biomechanical comparison of two seating systems for moderately involved cerebral-palsied children /." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66156.
Full text
10
Gonjo, Tomohiro. "A comparison of biomechanical and physiological characteristics between front crawl and back crawl." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/25462.
Full textAbstract:
Front crawl (FC) and back crawl (BC) are similar in terms of having alternating contributions of the arms combined with a six beat kick. However, the reason for the faster swimming times of FC than BC has not yet been established. There have been several studies in which the energy expenditure (Ė) of FC and BC were investigated. However, few researchers have compared Ė between the strokes. Also, although there have been some studies for FC using 3D motion analysis, few researchers have applied 3D motion analysis for BC. There have also been some studies in which the relationship between isokinetic torque produced on an isokinetic dynamometer and FC performance has been investigated, however, the relationship between isokinetic torque and BC performance is unclear. Therefore, the aim of this study was to determine why FC is faster than BC by investigating physiological and biomechanical differences between FC and BC. Ten Portuguese male national level swimmers were recruited for this study. Three studies were conducted to achieve the aim. In the first study, Ė of FC and BC at the same testing speed below the anaerobic threshold were investigated by measuring swimmers’ oxygen uptake. Kinematic variables of FC and BC below the anaerobic threshold were also measured by 3D motion analysis in the first study. In the second study, 3D motion kinematics of FC and BC at the same selected speeds were investigated. In the third study, kinematic differences between FC and BC at the same exercise intensities, and correlations between the kinematics and isokinetic muscular torques of the swimmer in FC and BC and their differences were assessed. Below the anaerobic threshold, Ė of the swimmers in BC was significantly greater than that in FC at the same speed although there were no differences in stroke frequency (SF), stroke length (SL) and stroke index (SI). Swimmers also had significantly higher Froude efficiency (ηF) in FC than in BC. Differences in several kinematic variables (range of motion of the foot, duration of non-propulsive phases, and intra-cycle velocity variation) suggested that swimmers expended greater energy in BC than in FC. Differences in other kinematic variables (body roll angle, hand speed/acceleration, yaw angle fluctuation, centre of mass displacement, and hand/foot displacements) suggested the possibility of resistive impulse being larger in BC than in FC during the stroke cycle. Thus, FC is more economical and efficient than BC because swimmers lose less energy to the water during the non-propulsive phase, and possibly have smaller resistive impulse in FC than in BC at speeds below the anaerobic threshold. At the same selected speeds above the anaerobic threshold, ηF in BC was significantly lower than that in FC, which was due to faster mean 3D hand speed during the stroke cycle in BC than in FC. The faster mean hand speed in BC than in FC was due to the faster 3D hand speed during the pull phase, and longer relative duration of the release and above-water phases in BC than in FC. SI was also larger in FC than in BC, which was due to longer SL in FC than in BC. The longer SL in FC than in BC was due to the longer duration of propulsive phases and probably smaller resistive impulse during the stroke cycle in FC than in BC. At the same selected exercise intensities, FC was faster than BC because of higher SF. The higher SF in FC than in BC was due to the longer duration of the above-water phase in BC than in FC, longer hand path distance during non-propulsive phases in BC than in FC, earlier timing of the hand entry in relation to the underwater phase of the other hand in FC than in BC. SF in both FC and BC was significantly correlated with shoulder adduction isokinetic torque of the swimmers, however, the effect of shoulder isokinetic torque on the difference in swimming performance between FC and BC required further investigation. In conclusion, FC is faster than BC because swimmers can achieve higher SF in FC than in BC, and FC is more economical and efficient than in BC with indirect evidence that resistive force are greater in BC than in FC.
11
Fletcher, Graham J. "The Pose™ method : a biomechanical and physiological comparison with heel-toe running." Thesis, Sheffield Hallam University, 2006. http://shura.shu.ac.uk/20204/.
Full textAbstract:
Research into endurance running performance (economy, optimal running biomechanics, and injury mechanisms) lacks a universal running technique; however, landing heel-toe identified eighty percent of runners. A new Gravitational hierarchical model of running was developed based upon a novel technique---Pose running---owing to deficiencies in the current hierarchical model (Hay and Reid, 1988) on the interaction of forces involved in running. A major deficiency in the current hierarchical model is viewing gravity as only active during flight. In contrast, the Gravitational hierarchical model defines a gravitational torque as the motive force in running. Ground reaction force is not a motive force but operates according to Newton's third law. The ground can only propel a runner forward via muscle activity, but leg and hip extensor muscles have consistently proven to be silent during leg extension. High Achilles tendon forces at terminal stance suggest the elastic recoil creates a re-bound effect in the vertical direction only, thus reducing work against gravity. Two experienced Pose runners were compared (study 1) with two experienced heel-toe runners using primary and secondary research variables derived from the Gravitational hierarchical model, which effectively distinguished the two techniques while establishing gravity as the motive force. For example, maximum horizontal acceleration of the centre of mass occurred before maximum horizontal ground reaction force, supporting the Gravitational hierarchical model that only a gravitational torque could create acceleration. Finally, sixteen male recreational endurance heel-toe runners (study 2 using the same primary variables as study 1) were randomly assigned into two groups where one group received a 7-hour Pose intervention over 7-days while the other group remained as heel-toe runners. A 2 x 2 mixed factorial ANOVA where group (control vs. treatment) and trial (pre to post changes) assessed the primary research variables. Significant interactions were explored using Tukey post hoc tests, which found significance (Pose runners pre-post test) for stance time (P= 0.001), centre of mass to support limb at 25 ms (P= 0.042), centre of mass displacement during stance (P = 0.001), knee flexion angular velocity during stance (P= 0.005) plus swing (P= 0.043) and stride frequency (P= 0.002). After 12-days the Pose group's posttest time-trial (2400 m) improved by a mean of 24.7 s compared with a 3 s decrease in the heel-toe group. No significant changes pre-post test, were found for an economy run (2400 m) at 3.35 m-s -1. A preliminary prospective 3-month injury report found no injury incidence in the Pose runners compared to six injuries in the heel-toe group. It was concluded, that the Pose technique is a valid biomechanical technique, which improved performance, while reducing injuries. Future work should further quantify gravity's role in accelerated running by ascertaining whether the horizontal acceleration of the centre of mass also occurs before maximal horizontal ground reaction force.
12
Lawson, LaJean R. "A Comparison of Eight Selected Sports Bras: Biomechanical Support, Overall Comfort Ratings and Overall Support Ratings." DigitalCommons@USU, 1985. https://digitalcommons.usu.edu/etd/4039.
Full textAbstract:
The purpose of this paper was to evaluate eight currently marketed sports bras for differences in control of vertical displacement of the breast, overall comfort scores, and overall support scores for A, B, C and D cup sizes. An additional goal was to determine and compare differences in the vertical displacement of the nude breast among the four cup size groups. To determine differences in vertical displacement, subjects were filmed while jogging on a treadmill, and film data were analyzed frame by frame. To determine differences in overall comfort and support ratings, subjects tested each of the eight bra styles under actual exercise conditions and subsequently completed an evaluation form. Significant differences in vertical displacement in the nude condition were found between the D cup size group and the other 3 cup sizes. Significant differences in the eight styles' abilities to control vertical displacement, and in overall comfort and support scores were found, both within the group as a whole and within each bra cup size group. Specific suggestions for further sports bra development and for individualized bra style selection are included.
13
Streicher, Matthew C. "KINEMATIC COMPARISON OF MARKER SET TECHNIQUES USED IN BIOMECHANICAL ANALYSIS OF THE PITCHING MOTION." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1176684209.
Full text
14
Wells, Julie. "Comparison of biomechanical and proprioceptive function following resurfacing arthroplasty and standard total hip replacement." Thesis, University of Strathclyde, 2009. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21998.
Full textAbstract:
Resurfacing arthroplasty is gaining popularity as an alternative method of hip joint reconstruction for younger individuals. Hip resurfacing has several perceived benefits over the conventional total hip arthroplasty (THA), including a greater range of motion offered by the larger diameter bearings and improved abductor muscle function due to femoral neck preservation. Literature reports that hip resurfacing often provides a 'natural' feel and allows greater functional return, which may be related to improved proprioception. However, existing studies have failed to fully substantiate the functional merits of resurfacing arthroplasty over those provided by the traditional stemmed THA. Outcomes were evaluated for 31 patients with primary unilateral resurfacing or standard stemmed THA at 3 and 12 months following surgery. Kinematic and kinetic data were collected while subjects completed level walking. stair ascent and stair descent activities. 3-dimensional hip moments and angles were compared between the arthroplasty groups. Threshold motion detection sense of the hip was tested to quantify hip joint proprioception, by administering passive abduction and flexion motion stimuli using a validated test rig and comparing threshold detection angles. Hip moments showed no statistically significant difference due to arthroplasty type. Slightly greater peak hip angles were achieved by those with standard THA. The resurfacing group showed greater walking velocities. Threshold detection angles were statistically similar. Resurfacing and standard THA demonstrated equivalent proprioceptive and functional outcomes. Motion detection sense did not differ due to arthroplasty type. Preserving the femoral offset did not appear to benefit abductor function and the greater diameter resurfacing bearings did not result in greater functional range of motion. The increased offset and greater head-neck ratio provided by the prosthetic neck may benefit abductor function and increase motion to an extent which meets the benefits of hip resurfacing. Given that there are greater risks and difficulties associated with hip resurfacing, standard THA may be viewed as the more desirable alternative for young active patients.
15
Assari, Soroush. "BIOMECHANICAL COMPARISON OF LOCKED PLATING AND SPIRAL BLADE RETROGRADE NAILING OF SUPRACONDYLAR FEMUR FRACTURES." Master's thesis, Temple University Libraries, 2011. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/205046.
Full textAbstract:
Mechanical EngineeringM.S.M.E.
Background: Comminuted supracondylar femur fractures in the elderly are often treated with either retrograde femoral nailing or locked plating. Early weight-bearing is typically restricted after fixing supracondylar fractures, thereby impairing the patient's mobilization. In general, surgeons are more comfortable allowing early weight-bearing of long bone fractures after nailing rather than plating, but early studies of retrograde nails for supracondylar fractures using standard distal locking showed poor fixation compared with locked plating. Newer generation distal locking techniques, such as the spiral blade, may demonstrate improved fixation, potentially allowing early weight bearing. The purpose of this study is to biomechanically compare locked plating with retrograde nailing of osteoporotic supracondylar femur fractures with simulated physiologic weight-bearing in the post-operative period. Methods: The Locking Condylar Plate (LCP) and Retrograde/Antegrade EX Femoral Nail (RAFN) with spiral blade locking were tested using 10 paired elderly cadaveric femurs, divided into normal and low BMD groups, with a simulated AO/OTA type 33-A3 supracondylar femur fracture. Each specimen was subjected to 200,000 loading cycles simulating six weeks of postoperative recovery with full weight-bearing for an average individual and the construct subsidence and axial stiffness were measured. Results: LCP fixation compared to RAFN showed higher axial stiffness for normal and low BMD groups (80% and 57% respectively). After cyclic loading, axial stiffness of both constructs decreased by 20% and RAFN fixation resulted in twice as much subsidence (1.9±0.6 mm). Two RAFN constructs with low BMD failed after a few cycles whereas the matched pairs fixed with LCP failed after 68,000 and 100,000 cycles. Conclusions: The LCP construct was stiffer than RAFN construct. Early weight bearing may cause 3-4 mm of subsidence in elderly patients with low BMD. However, because of the observed failures in two of the samples treated with RAFN in the low BMD group, early weight bearing is not recommended in osteoporotic bones treated with RAFN.
Temple University--Theses
16
Samaneein, Katika. "Biomechanical comparison of a rigid and dynamic seating system for children with special needs." Thesis, University of Strathclyde, 2014. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=22774.
Full textAbstract:
In wheelchair users who experience strong extensor spasms, high muscular forces exerted during the episode may lead to high contact forces between the child and the wheelchair. The forces may be physically powerful enough to cause pain and injury to the child, and can damage or break components of the wheelchair. Dynamic seating systems have been used in an attempt to reduce these contact forces. Such systems permit forward and backward movements as the occupant extends and retracts their body, consequently they are assumed to be beneficial to patients with strong extensor spasms. Questions about the magnitude and direction of the loads which these children can exert through a seating system have been raised. Additionally, the effectiveness of using dynamic components and the advantages of prolonged use remain unclear. The aim of this study was to quantify and compare the imparted forces on equivalent rigid and dynamic seating systems throughout activities of daily living. To achieve this, a mobile strain gauged seating system was developed which allowed the strain generated in the back and footrest components to be measured. At a certain instant of exerted force, the strain data was converted into force and moments acting on the backrest and footrests in three dimensions, assuming static equilibrium. The position of the resultant force on the backrest, termed the centre of pressure (COP), was also calculated. This project shows that the development of a fully mobile data acquisition system is achievable and practical. Results obtained from twelve children during their community based activity of daily living showed no significant differences in the mean and peak interface forces on the backrest between the rigid and dynamic systems. However, when using the dynamic backrest system, a significant decrease in force and bending moments were observed on the right footrest, the dominant side of most participants. Conversely, for the left footrest only the average bending moment about the transverse axis through the ankle showed a statistically significant decrease, with no significant difference demonstrated between the other variables for the two backrest systems. This work included a long-term case study using the dynamic backrest seating system. The data did not elicit any observable differences of changing in movement, probably due to the relative inactivity of the recruited volunteer. Further work and recruitment should focus on users who exhibit strong extensor spasms, as this work suggest that these are the population who may benefit the most from dynamic seating.
17
Janicek, John Charles. "In vitro three dimensional biomechanical comparison of two internal fixation methods in equine adult radii." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/4927.
Full textAbstract:
Thesis (M.S.)--University of Missouri-Columbia, 2007."August 2007" The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Includes bibliographical references.
18
Verma, Saurabh. "Microwave Synthesis of Nanocrystalline Hydroxy Apatite and Comparison of Its Biomechanical Properties with TiO2 Structures." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3624.
Full textAbstract:
Nanocrystalline hydroxyapatite (HAp) powder of size 10-20 nm was synthesized applying microwave radiation using calcium nitrate tetrahydrate and sodium phosphate dibasic anhydrous as the starting materials. Microwave power of 600 W and Ca/P ratio of 1.66 in the starting chemicals served as the major factors in the synthesis of nanocrystalline HAp powder. Phase composition and evolution were studied using X-ray diffraction (XRD) technique. Morphology, agglomeration and particle-size of the synthesized powder were studied using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) techniques. Energy Dispersive Spectrum (EDS) was used to determine the elemental composition of the powder. Thermal properties were investigated using Thermogravimetric (TG) and Differential Thermal Analysis (DTA) and, Fourier Transform Infrared Spectroscopy (FTIR). As-synthesized HAP and TiO2 powder was uniaxially compacted into cylindrical pellets at a pressure of 78.69 MPa and sintered at high temperature to examine the effects of sintering on nano powder particles, densification behavior, phase evolution and mechanical properties. Phase evolution was studied using XRD whereas microstructure evolution was studied by SEM. To determine the mechanical properties Vickers hardness and biaxial flexural strength tests were performed. Biodegradability and biomechanical strength of nano-HAp and TiO2 samples sintered at high temperature was assessed in Simulated Body Fluid (SBF) having ionic concentration as that of human plasma. Biodegradation and change in mechanical properties of the sintered samples when kept in SBF and maintained in a dynamic condition were studied in terms of weight loss, change in Vickers hardness and biaxial flexural strength as a function of time. Highly crystalline HAp powder was achieved after microwave synthesis with average particle size in the range of 10-20 nm which was further confirmed by HR-TEM and SEM. Calcination of the synthesized powder at 500[degrees]C for 2 h increased the average particle size to 21 nm. EDS confirmed the elemental composition of the powder. FTIR analysis showed the presence of phosphate band which confirmed the presence of HAp at high temperature. TG analysis showed 23% weight-loss upon heating up to 1200[degrees]C, contributed by the removal of adsorbed and possible lattice water, decarboxylation of HAp or condensation of HPO42- releasing water. HAp along with [Beta]NaCaPO4 and Na3Ca6(PO4)5 was observed at 950[degrees]C, 1100[degrees]C and 1200[degrees]C. Density of HAp samples continued increasing with the increase in temperature from 1100[degrees]C to 1250[degrees]C and sintered density of 2.88 g/cc was obtained at 1250[degrees]C. Hardness and Biaxial strength of the HAp samples increased with temperature and maximum hardness value of 249.53 [plus or minus] 3.98 HV and biaxial flexural strength of 52.07 [plus or minus] 4.96 MPa were observed for samples sintered at 1250[degrees]C. Biaxial strength and hardness of TiO2 samples increased with temperature. Maximum biaxial flexural strength of 125.5 [plus or minus] 11.07 MPa and maximum hardness of 643.27 [plus or minus] 7.96 HV were observed for the TiO2 sample sintered at 1500[degrees]C which was much more than that of sintered HAp samples. Decrease in mass, hardness and biaxial strength of HAp samples sintered at 1250[degrees]C and TiO2 samples sintered at 1400[degrees]C showed biodegradation in SBF, maintained in a dynamic state, as a function of time. Increase in mass was observed for the HAp samples in SBF during the fourth week.M.S.M.S.E.
Department of Mechanical, Materials and Aerospace Engineering;
Engineering and Computer Science
Materials Science & Engr MSMSE
19
Desai, Krishna P. "A Biomechanical Comparison of Locking Compression Plate Constructs with Plugs/Screws in Osteoporotic Bone Model." Wright State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wright1271706065.
Full text
20
Chapman, Tara. "Morphometric, functional and biomechanical analysis of a virtual Neandertal in comparison with anatomically modern humans." Doctoral thesis, Universite Libre de Bruxelles, 2017. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/251406.
Full textAbstract:
Early anthropological examination of Neandertal skeletal material by Marcellin Boule gave rise to popular images of Neandertals as brutish, ape-like creatures who walked hunched over with bent knees and a shuffling gait. Today, it is generally thought that Neandertals moved in a similar manner to humans with locomotive patterns within human ranges of variation and a bipedal gait likely to be indistinguishable from that of modern humans However, this hypothesis has not been tested by using the Neandertal skeleton as a whole. There is no complete Neandertal skeleton in the fossil record. The aim of this thesis was to reconstruct a complete virtual skeleton of a Neandertal based on the Spy II remains for educational museology purposes and for biomechanical analysis. Comparative analyses of Neandertal and modern human bones (pelvis, femur, rib) using different reference populations from Belgium were also undertaken. These studies were performed with a view to further understanding Neandertal bone morphology in comparison to modern humans, to assist in the reconstruction of the Neandertal Spy II skeleton and to aid in biomechanical analysis. A study on the sex determination of the pelves showed that there was no difference between physical linear measurements and virtual measurements, which was an important validation. The lhpFusionBox musculoskeletal software, which was developed at ULB, was used to scale available Neandertal and modern human bones to reconstruct the skeleton. Previous methods in the literature have only scaled bones of the same nature. A novel and validated scaling method was used to scale the Kebara 2 pelvis to the dimensions of the Spy II femur (as Spy II only has a small piece of sacrum) via the Neandertal 1 femur and pelvis. The reconstruction of a complete Neandertal skeleton based on the Spy II remains enabled the validation of individual reconstructions of bones, reconstructed long bones to be compared together with other limb proportions of Neandertals, stature estimation to be performed, and questions to be asked on previous attributions of bones to Spy II. The thoracic shape of Neandertals has previously been subject to much debate with many authors stating that it would have been markedly different from modern humans. This thesis created a Neandertal thorax with assistance from rib and thoracic experts from different domains using the Kebara 2 remains. One reconstruction was found to have a similar shape to modern humans and the other a markedly different shape, highlighting difficulties in thoracic reconstruction of fossil hominids.The full scale Neandertal skeleton has been printed in 3D and used in RBINS and other Museums in Europe as a reference for the Neandertal Skeleton in permanent gallery exhibitions. This skeleton is also used as the base for Neandertal hyper-realistic artistic reconstructions based on scientific evidence by the artists, the Kennis brothers which are in the Centre d'Interprétation de l'Homme de Spy, the National History Museum, London and other museums around the world. The reconstruction of a complete lower limb also allowed biomechanical studies. The various biomechanical studies have looked at what happens when you fuse the motion of a living modern human to Neandertal bones. We cannot say that the Neandertal would have walked or squatted similar to the volunteers in the studies but we can say that the morphology of their bones would have enabled them to walk or squat in this way. All the moment arms of the major muscles of the hip and knee were analysed and it was demonstrated that the Neandertal models largely had greater muscle moment arms than the AMH models meaning Neandertals could have had a significant mechanical advantage over modern humans. These studies demonstrate Neandertal postcranial morphology can be different to modern humans although certain aspects may be more similar than previously thought.Historiquement, le travaux de Marcellin Boule ont donné lieu à des représentations populaires de Néandertaliens vus comme des créatures simiesques bestiales qui se déplaçaient courbés avec des genoux pliés en traînant les pieds. Aujourd'hui, il est généralement admis que les Néandertaliens se déplaçaient d'une manière similaire à l'homme moderne avec une locomotion bipède. Toutefois, cette hypothèse n'a pas été encore testée sur un squelette néandertalien dans son ensemble. Comme il n’existe aucun squelette de Néandertalien entier, le but de cette thèse était de reconstituer un squelette virtuel complet sur la base des restes de Spy II à des fins éducatives de muséologie et pour l'analyse biomécanique.Des analyses comparatives d’os de Néandertalien et d’humains modernes (bassin, fémur, côtes) en utilisant diverses populations de référence de Belgique ont également été menées. Ces études ont été réalisées en vue de comprendre la morphologie néandertalienne, pour aider à la reconstruction du squelette Spy II et à l'analyse biomécanique. Une étude sur la détermination du sexe à partir des pelvis a montré qu'il n'y avait pas de différence entre les mesures linéaires physiques et les mesures virtuelles, ce qui était une validation importante.Le logiciel musculosquelettique lhpFusionBox, développé à l'ULB, a été utilisé pour reconstruire le squelette. Un nouveau procédé de mise à l'échelle validé a été utilisé pour mettre à l'échelle le bassin de Kebara 2 aux dimensions du fémur de Spy II (comme Spy II ne possède qu’un petit fragment de sacrum) via le fémur et le bassin de Neandertal 1. La reconstruction d'un squelette complet de Néandertalien a apporté de nouvelles connaissances sur cette espèce dans différents domaines. Elle a permis la validation des reconstructions individuelles des os, de comparer les os longs reconstruits avec d'autres proportions des membres de Néandertaliens, de faire une estimation de stature, et de reconsidérer les attributions antérieures d'os à Spy II. La forme thoracique des Néandertaliens a déjà fait l'objet de nombreux débats. Cette reconstruction de Spy II, creé avec l'aide des experts utilisant les restes de Kebara 2, montre deux formes de reconstruction differentes, et indique les difficultés de la reconstruction thoracique des fossiles. Le squelette virtuel complet a été imprimé en 3D et utilisé par l’IRSNB et d'autres musées en Europe comme une référence de squelette néandertalien. Ce squelette a également été utilisé comme base pour les reconstructions artistiques hyper-réalistes de Néandertaliens, basées sur des données scientifiques, par les artistes Kennis et sont présentés dans les musées du monde entier. La reconstruction d'un membre inférieur complet a également permis des études biomécaniques. Ces dernières ont étudié la fusion du mouvement d'un homme moderne actuel avec des os néandertaliens. On ne peut pas se prononcer si le Néandertalien marchait ou s’accroupissait de manière similaire aux hommes modernes, mais on peut affirmer que leur morphologie osseuse leur permettait de marcher ou de s’accroupir de cette façon. Tous les bras de levier des principaux muscles de la hanche et du genou ont été analysés et il a été démontré que les Néandertaliens avaient les bras de levier plus grand que le modèle homme moderne signifiant Néandertaliens auraient eu un avantage mécanique important. Cette études démontre que des aspects de la morphologie postcrânienne néandertalienne soient différents, bien que certains d’entre eux soient plus semblables aux humains modernes qu'on ne le pensait.
Doctorat en Sciences biomédicales et pharmaceutiques (Médecine)
info:eu-repo/semantics/nonPublished
21
Parikh, Rachit D. "Biomechanical Comparison of Various Posterior Dynamic Stabilization Systems for Different Grades of Facetectomy and Decompression Surgery." University of Toledo / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1290199598.
Full text
22
Doulgeris, James. "Biomechanical Comparison of Titanium and Cobalt Chromium Pedicle Screw Rods in an Unstable Cadaveric Lumbar Spine." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4812.
Full textAbstract:
Pedicle screw-rod instrumentation is considered a standard treatment for spinal instability, and titanium is the most common material for this application. Cobalt-chromium has several advantages over titanium and is generating interest in orthopedic practice. The aim of this study was to compare titanium versus cobalt-chromium rods in posterior fusion, with and without transverse connectors, through in vitro biomechanical testing and determine the optimal configuration.
Six cadaveric lumbar spines (L1-S1) were used. Posterior and middle column injuries were simulated at L3-L5 and different pedicle screw constructs were implanted. Specimens were subjected to flexibility tests and range of motion, intradiscal pressure and axial rotation energy loss were statistically compared among the following conditions: intact, titanium rods (without transverse connectors), titanium rods with transverse connectors, cobalt-chromium rods (without transverse connectors) and cobalt-chromium rods with transverse connectors. The novel measurement of energy loss was examined to determine its viability in fusion investigations.
All fusion constructs significantly (p0.05) were observed in axial rotation among all conditions. Intradiscal pressure significantly increased (p≤0.01) after fusion, except for the cobalt-chrome conditions in extension (p≥0.06), and no significant differences (p>0.99) were found among fixation constructs. Energy loss, differences became significant between the cobalt-chrome with transverse connector condition with respect to the cobalt-chrome (p=0.05) and titanium (p
There is not enough evidence to support that the cobalt-chrome rods performed biomechanically different than the titanium rods. The use of titanium rods may be more beneficial because there is a lower probability of corrosion. The inclusion of the transverse connector only increased stability for the cobalt-chromium construct in axial rotation, which suggests that it is beneficial in complete facetectomy procedures.
23
Wong, Mark Steven. "Biomechanical Comparison of Wire Circlage and Rigid Plate Fixation for Median Sternotomy Closure in Human Cadaver Specimens." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/280.
Full textAbstract:
Background:
Over 700,000 patients per year undergo open-heart surgery. Healing complication rates can be up to 5% of patients who undergo this procedure, with a morbidity rate of 50% if mediastinitis supervenes. A secure and rigid fixation of surgically divided sternum is critical to avoid healing complications. The purpose of this study was to compare the yield load, construct stiffness, ultimate load, displacement at ultimate load, and post-yield behavior of three sternotomy closure methods (Peristernal wires or Sternalock titanium plates) when stressed in each of three directions: lateral distraction, rostro-caudal (longitudinal) shear distraction, and anterior-posterior (transverse) shear in a cadaveric model.
Methods:
Forty-two fresh cadaver models were divided into three test groups: group A, B, and C. A cardiothoracic surgeon divided each cadaveric sternum longitudinally and repaired peristernal wires or one of two Sternalock configurations. Tests were performed using a materials testing system that applied force at a constant displacement rate in a uniaxial direction until the construct catastrophically failed. Mechanical behavior was monitored using a 3D texture correlation system to create a real-time three-dimensional representation of strain directions. The resulting displacement pattern is analogous to a finite element contour plot of displacements, Lagrange Strain, or velocity. Statistical analysis was used to show the different mechanical properties of each closure method.
Results:
When loaded in lateral distraction, both Sternalock configurations surpassed the rigidity of peristernal wires by 600%. Some evidence was also found linking Sternalock with stiffer behavior in the rostro-caudal direction. Though not statistically significant, a trend was observed showing that constructs using the Sternalock also had higher yield loads, as well as, less post-yield displacement when compared to peristernal wires.
Conclusions:
Data gathered showed the superior performance of the Sternalock system in stiffness in both longitudinal distraction and rostro-caudal shear. Implications for use of the Sternalock system are faster healing times, lower complication rates, and success of the procedure.
24
Malan, Freddie. "An in vitro biomechanical comparison between intramedullary pinning and the use of plates in the dachshund tibia." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/24914.
Full textAbstract:
The dachshund, a chondrodystrophic dog breed, presents a unique challenge in the treatment of tibial fractures by having short and curvaceous tibiae, leading to high implant failure risk. In this study, intramedullary pins with full cerclage wires as an option in the treatment of oblique diaphyseal tibial fractures was studied in vitro. This fixation technique was biomechanically compared with the current gold standard in internal stabilization, namely bone plates and screws. Twenty tibiae recovered from adult dachshund cadavers were randomly allocated into two groups of ten bones each. Oblique fractures running in a proximo-cranial-disto-caudal direction in the middle third of the tibial diaphysis were simulated by osteotomy and each bone repaired by using one of the following methods: - Pre-bent intramedullary pin, filling 40% to 60% of the medullary cavity at its narrowest point, inserted normograde and combined with a set of three full cerclage wires (group 1).
- Lag screw at the osteotomy site, combined with a six hole 2.7 mm contoured dynamic compression plate and cortical screws in neutral mode (group 2).
Die dachshund, ‘n chondrodistrofiese honderas, bied ‘n unieke uitdaging in die behandeling van frakture van die tibia, deurdat hulle tibias kort en krom is, wat lei tot ‘n hoë risiko van inplantaat mislukking. In hierdie studie is intramedullêre penne met vol sirkeldrade as ‘n keuse in die behandeling van skuins frakture van die tibiale skag in vitro bestudeer. Hierdie tegniek van herstel is vergelyk met die huidige goue standaard in interne stabilisering, naamlik beenplate en skroewe. Twintig tibias wat van volwasse dachshund kadawers herwin is, is lukraak aan twee groepe van tien bene elk toegewys. Skuins frakture in ‘n proksimo-kranio-disto-koudale rigting in die middelste derde van die tibiale skag is nageboots deur ‘n osteotomie, waarna elke been herstel is deur die gebruik van een van die volgende metodes:
- Vooraf gebuigde intramedullêre pen, wat 40% tot 60% van die murgholte by die dunste punt vul, normograad geplaas en gekombineer met ‘n stel van drie vol sirkeldrade (groep 1).
- Trekskroef by die osteotomie area, gekombineer met ‘n ses-gat 2.7 mm gekontoerde dinamiese drukplaat en kortikale skroewe geplaas op neutrale wyse (groep 2).
Dissertation (MSc)--University of Pretoria, 2012.
Companion Animal Clinical Studies
unrestricted
25
O'Donnell, James B. "A Biomechanical Comparison of an Interspinous Fixation Device and a Pedicle Screw and Rod System for Posterior Fixation." University of Toledo / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1271342058.
Full text
26
Bras, Jose J. "Biomechanical comparison of a less invasive technique and the current accepted technique for arthrodesis of the equine proximal interphalangeal joint." Thesis, Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/4252.
Full text
27
Ball, Rebecca L. "In Vitro Biomechanical Comparison of Double Versus Single Plated Tibial Plateau Leveling Osteotomy Constructs in Axial Loading." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1243976640.
Full text
28
Feng, Gang [Verfasser]. "Biomechanical comparison of anterior screw fixation techniques for type II odontoid fractures : One- versus two-screw fixation / Gang Feng." Lübeck : Zentrale Hochschulbibliothek Lübeck, 2011. http://d-nb.info/1017565600/34.
Full text
29
Chokhandre, Snehal K. "A Biomechanical Comparison Between a Biological Intervertebral Disc and Synthetic Intervertebral Disc Implants Under Complex Loading: An In Vitro Study." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1187022568.
Full text
30
Deryas, Wahid Fahmy. "Biomechanical evaluation of femoral strain patterns after implantation of cemented stems in comparison to the strain patterns after implantation of cementless stems a photoelastic study." München Hieronymus, 2007. http://d-nb.info/999949136/34.
Full text
31
Filipowicz, Dean. "A Biomechanical Comparison of 3.5 Locking Compression Plate Fixation to 3.5 Limited Contact Dynamic Compression Plate Fixation in a Canine Cadaveric Distal Humeral Metaphyseal Gap Model." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/33558.
Full textAbstract:
Objective- To compare the biomechanical properties of 3.5 locking compression plate (LCP) fixation to 3.5 limited contact dynamic compression plate (LC-DCP) fixation in a canine cadaveric, distal humeral metaphyseal gap model in static axial compression and cyclic axial compression and torsion.
Study Design- Biomechanical in vitro study.
Sample Population- 30 paired humeri from adult, medium to large breed dogs.
Methods- Testing was performed monotonically to failure in axial compression on ten pairs of humeri, cyclically in axial compression for 10,000 cycles on ten pairs and cyclically in torsion for 500 cycles on the last ten pairs.
Results- Humeral constructs stabilized with LCPs were significantly stiffer than those plated with LC-DCPs when loaded in axial compression (P=0.0004). When cyclically loaded in axial compression over 10,000 cycles, the LC-DCP constructs were significantly stiffer than those constructs stabilized with LCPs (P=0.0029). Constructs plated with LC-DCPs were significantly more resistant to torsion over 500 cycles than those plated with LCPs (P<0.0001), though no difference was detected during the first 280 cycles.
Conclusions- The increased stiffness of LCP constructs in monotonic loading compared to constructs stabilized with non-locking plates may be attributed to the stability afforded by the plate-screw interface of locking plates. The LCP constructs demonstrated less stiffness in dynamic testing in this model, likely due to plate-bone offset secondary to non-anatomic contouring and occasional incomplete seating of the locking screws when using the torque-limiting screw driver.
Clinical Relevance- LCPs yield less stiff fixation under dynamic loading than conventional LC-DCPs when applied to severely comminuted, metaphyseal fractures. Improving anatomical contouring of the plate and insuring complete screw insertion into the locking plate hole may improve stiffness when using LCPs in comminuted fractures.Master of Science
32
Deryas, Wahid Fahmy [Verfasser]. "Biomechanical evaluation of femoral strain patterns after implantation of cemented stems in comparison to the strain patterns after implantation of cementless stems : a photoelastic study / Wahid Fahmy Deryas." München : Hieronymus, 2007. http://d-nb.info/999949136/34.
Full text
33
Schopper, Clemens [Verfasser]. "Biomechanical evaluation of the femoral neck fracture fixation technique with the new implant FNS in comparison to DHS Blade, DHS Screw with antirotation screw and Three Cannulated Screws / Clemens Schopper." Ulm : Universität Ulm, 2018. http://d-nb.info/1151938327/34.
Full text
34
Schopper, Clemens Oliver [Verfasser]. "Biomechanical evaluation of the femoral neck fracture fixation technique with the new implant FNS in comparison to DHS Blade, DHS Screw with antirotation screw and Three Cannulated Screws / Clemens Schopper." Ulm : Universität Ulm, 2018. http://d-nb.info/1151938327/34.
Full text
35
Schlabs, Thomas [Verfasser]. "Comparison of cardiovascular and biomechanical parameters of supine lower body negative pressure (LBNP) and upright lower body positive pressure (LBPP) to simulate activity in 1/6 G and 3/8 G / Thomas Schlabs." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2016. http://d-nb.info/1082237493/34.
Full text
36
Konz, Suzanne M. "Technique and Performance Level Comparisons of Male and Female Hammer Throwers." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1660.pdf.
Full text
37
Henderson, Melanie Ellen. "Biomechanical comparison of netball shooting technique a six-week jump training intervention : this thesis is presented in partial fulfillment of the requirements for the Master of Health Science degree at Auckland University of Technology, March 26th 2004." Full thesis. Abstract, 2004.
Find full text
38
Hawit, Ramzi P. Mr. "Development of a Standardized Method for Comparing Biomechanical Properties of Various Sternal Closure Techniques." DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/707.
Full textAbstract:
Background:
33.6% of all deaths in America are caused by cardiovascular disease. An estimated 82.6 million adults (>1 in 3) in America have some form of cardiovascular disease. There were over 400,000 bypass surgeries requiring open-heart surgery. Sternal dehiscence is associated with a morbidity rate of over 47% if mediastinitis supervenes. A rigid closure is required to avoid healing complications, and wire, plates, and bands are all used in an attempt to make a better closure. The purpose of this study it to compare multiple closures and validate a new testing method.
Methods:
Polyurethane foam blocks will be used, as an alternative to cadavers, to provide homogeneous samples to test and compare multiple closure techniques. Each closure was performed by an engineer after instruction from a cardiothoracic surgeon and the SternaLock plate manufacturers. Seven different closure techniques (single suture, double suture, figure-eight suture, Robicsek weave, Sternalock Silver, Sternalock Blu, and Sternalock Wide Ladder) were compared in both lateral distraction and longitudinal shear. Statistical analysis was used to show the differences in stiffness, yield force, failure force, and yield displacement of each closure method.
Results:
Under lateral distraction, double wire closure showed the greatest stiffness followed by the Sternalock plates. The Sternalock plates had the greatest failure and yield forces, whereas the double wire performed significantly poorer. The longitudinal testing revealed that the wires provide no resistance to the shearing forces on the sternum, but the screws for plates can allow for multidirectional loading.
Conclusions:
Overall Sternalock plates are less likely to fail in all directions compared to wired closures. Even though double wire closures displayed a higher average lateral stiffness, the high stress concentrations created by wires allowed for easy foam cutting and much lower yield force and failure force. Testing using foam blocks as sternal analogues produces highly reproducible results, with less variance than cadaveric tests.
39
Ford, Jonathan M. "Skeletal Muscle Contraction Simulation: A Comparison in Modeling." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4814.
Full textAbstract:
Computer generated three-dimensional (3-D) models are being used at increasing rates in the fields of entertainment, education, research, and engineering. One of the aspects of interest includes the behavior and function of the musculoskeletal system. One such tool used by engineers is the finite element method (FEM) to simulate the physics behind muscle mechanics. There are several ways to represent 3-D muscle geometry, namely a bulk, a central line of action and a spline model. The purpose of this study is to exmine how these three representations affect the overall outcome of muscle movement. This is examined in a series of phases with Phase I using primitive geometry as a simplistic representation of muscle. Phases II and III add anatomical representations of the shoulder joint with increasing complexity. Two methods of contraction focused on an applied maximal force (Fmax) and prescribed displacement. Further analyses tested the variability of material properties as well as simulated injury scenarios. The results were compared based on displacement, von Mises stress and solve time. As expected, more complex models took longer to solve. It was also supported that applied force is a preferred method of contraction as it allows for antagonistic and synergistic interaction between muscles. The most important result found in these studies was the consistency in the levels of displacement and stress distribution across the three different 3-D representations of muscle. This stability allows for the interchangeability between the three different representations of muscles and will permit researchers to choose to use either a bulk, central line of action or a spline model. The determination of which 3-D representation to use lies in what physical phenomenon (motion, injury etc.) is being simulated.
40
Chamberlain, Christin R. Padua Darin A. "Comparison of lower extremity biomechanics between female Division I gymnastic, lacrosse, and soccer athletes." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,443.
Full textAbstract:
Thesis (M.A.)--University of North Carolina at Chapel Hill, 2006.Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Master of Arts in the Department of Exercise and Sport Science (Athletic Training)." Discipline: Exercise and Sports Science; Department/School: Exercise and Sport Science.
41
Griswold, Emily K. "Comparison of Jump Landings in Figure Skaters While Barefoot and Wearing Skates." Ohio University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1490346788544816.
Full text
42
Brisson, Nicholas. "A Comparison of Preoperative and Postoperative Lower-extremity Joint Biomechanics of Patients with Cam Femoroacetabular Impingement." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20256.
Full textAbstract:
Surgery to correct cam femoroacetabular impingement (FAI) is increasingly popular. Despite this, no known study has used motion analysis and ground reaction forces to quantify the outcome of surgery for FAI. The goal of this study was to compare the preoperative and postoperative lower-extremity joint kinematic and kinetic measurements of cam FAI patients during activities of daily living with use of a high-speed motion capture system and force platforms. We hypothesized that the lower-extremity joint mechanics of FAI patients during level walking and maximal squatting would resemble more those of healthy control subjects, after surgery. Ten patients with unilateral symptomatic cam FAI, who underwent corrective surgery using an open or combined technique, performed walking and maximal depth squatting trials preoperatively and postoperatively. Thirteen healthy control subjects, matched for age, sex and body mass index, provided normative data. Results showed that postoperatively, FAI patients had reduced hip ROM in the frontal and sagittal planes, produced smaller peak hip abduction and external rotation moments, and generated less peak hip power compared to the control group during level walking. During maximal squatting, postoperative FAI patients squatted to a greater depth, and had larger knee flexion and ankle dorsiflexion angles, as well as the sum of all joint angles of the affected limb at maximal depth compared to the preoperative values. The lower-extremity joint and pelvic mechanics of FAI patients did not fully return to normal after surgery. Although surgery seemed to reduce hip pain and restore a normal femoral head-neck offset, it further impaired muscle function as a result of muscle incisions. More research is needed to determine the effects of muscle incisions, which could help improve surgical techniques and develop better rehabilitation programs for FAI patients.
43
Kowalski, Erik. "Kinematics and Kinetics of the Lower Limb In Uphill and Downhill Running: A Comparison of Forefoot Strike and Rearfoot Strike Runners." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33170.
Full textAbstract:
his study investigated the lower limb biomechanics during downhill and uphill running in habitual forefoot strike and habitual rearfoot strike runners. Fifteen habitual forefoot strike and fifteen habitual rearfoot strike recreational male runners ran at 3 m/s ± 5% during level, uphill and downhill overground running on a ramp mounted at 6° and 9°. Results showed that hill running had similar impacts on joint angles in rearfoot strike and forefoot strike runners, causing a decrease in hip flexion at initial contact during downhill running, an increase in knee flexion angle at initial contact during uphill running and a decrease in peak hip flexion angle. In addition to differences in ankle joint angle due to landing pattern difference between rearfoot strike and forefoot strike runners, forefoot strike runners had a more flexed hip angle during downhill running. Forefoot strike runners had an absent impact peak in all running conditions, while the impact peaks only decreased during the uphill conditions in rearfoot strike runners. Active peaks decreased during the downhill conditions in forefoot strike runners while active loading rates increased during downhill conditions in rearfoot strike runners. Compared to the level condition, parallel braking peaks were larger during downhill conditions and parallel propulsive peaks were larger during uphill conditions. Peak hip flexion moment was significantly greater while peak knee flexion moment was significantly lower in both groups during the downhill 9° condition. Forefoot strike runners had larger peak plantar flexion moments and peak ankle power absorption compared to rearfoot strike runners during all conditions. Forefoot strike runners had decreased peak power absorption at the knee joint during downhill and level running conditions. Combined with previous biomechanics studies, our findings of no impact peak in forefoot strike runners suggests that this landing pattern may have potential in reducing overuse running injuries. Forefoot strike running reduces loading at the knee joint and can be used as an effective strategy to reduce stress at the knee joint experienced with rearfoot strike running.
44
Smidebush, Megan M. "MUSCLE ACTIVATION ANALYSIS WITH KINEMATIC COMPARISON BETWEEN WIND-UP AND STRETCH PITCHING WITH RESPECT TO THE UPPER AND LOWER EXTREMITIES." UKnowledge, 2018. https://uknowledge.uky.edu/khp_etds/49.
Full textAbstract:
Introduction: Baseball pitching is considered one of the most intense aspects within the game of baseball, as well as the most complicated dynamic throwing task in all of sports. The biomechanics of pitching have been heavily investigated in an attempt to identify optimal pitching mechanics in terms of pitching performance. Previous quantified upper body kinetics research has concluded that improved muscle strength is needed in attempting to achieve adequate upper body kinetics and efficient pitching performances. Therefore, it is the purpose of this research study to compare the lower extremity muscle and upper extremity muscle activation patterns and kinematic variables associated with the curveball pitch and the fastball pitch when pitching from the wind-up and stretch position. Methods: Twelve skilled (competed at the NCAA collegiate level) baseball pitchers volunteered to be research subjects for this study. The participants were fitted with six surface electromyography (EMG) bipolar electrodes (Delsys Inc., Boston, Massachusetts) on the stride leg biceps femoris, medial gastrocnemius, ipsilateral side (throwing arm side) lower trapezius, upper trapezius, triceps brachii and biceps brachii. Each participant underwent maximum voluntary isometric contraction (MVIC) testing and then performed a pitching analysis. All EMG variables of interest were normalized using MVIC data and then compared between pitching types and pitch delivery. Shoulder rotation, shoulder abduction, elbow flexion and extension, elbow angular velocity and pelvis rotation were determined using motion capture (Motion Analysis Corp., Santa Rosa, SA) and Visual 3D software (C-Motion Inc., Germantown, MD). Paired t-tests and factorial analyses were performed using SPSS (p ≤ 0.05). Results and Discussion: Significant differences in the peak and mean muscle activity for the fastball and curveball pitched from wind-up and stretch position were observed. Significant differences in the kinematic variables between the fastball and curveball from the wind- up and stretch were also observed. These findings suggest that upper and lower muscle activity could be associated with enhanced pitching technique and pitching performance. Pitching kinematic differences associated with the diverse pitch types as well as the multiple pitch deliveries may impact the overall “wear and tear” on a pitcher’s health and pitching arm. Conclusions: Many differences were found, between both the pitching type and the pitching delivery as well as the kinematic variables. These findings suggest that upper and lower muscle activity could be associated with enhanced pitching technique and pitching performance to keep a baseball pitcher healthy and on the pitching mound longer into the season, decreasing the rate of injury. Shoulder rotation and pelvis rotation, as well as the elbow angular velocity and elbow flexion-extension, have an impact on the pitcher’s ability to stay off the disabled list and in the game longer. Determining pitch types along with delivery types that enhance the pitcher’s ability to stay active without injury will provide a way to make the game of baseball safer for the future generation of all stars.
45
Heebner, Maryellen. "Comparison of Different Transmission Approaches to Optimize Exoskeleton Efficiency." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1576609767744357.
Full text
46
Agrawal, Vibhor. "A Comparison of Gait Kinetics between Prosthetic Feet during Functional Activities - Symmetry in External Work Approach." Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_dissertations/456.
Full textAbstract:
Background: Unilateral transtibial amputees (TTAs) show subtle gait variations while using different prosthetic feet. These variations have not been detected consistently with previous experimental measures. In this research project a novel measure for quantifying kinetic gait differences among prosthetic feet, called Symmetry in External Work (SEW), was introduced. The reliability of the SEW measure was calculated and its correlation with selected clinical measures was determined. The SEW measure was then applied to determine gait differences among four categories of prosthetic feet during various functional activities. Methodology: The study was conducted in three phases. Phase I was a single subject Pilot study to determine the sensitivity of the SEW measure to different prosthetic feet and functional activities. In Phase II, test-retest reliability of the SEW measure was determined for 5 TTAs during the functional activities of level walking, incline walking, decline walking, ascending stairs, descending stairs, sit-to-stand and stand-to-sit. The agreement between SEW values obtained from F-scan and force plates was also calculated. In Phase III, 11 subjects underwent 6 testing sessions over a period of 10-12 weeks. In session 1 subjects were tested wearing their existing prostheses (Baseline session), were given specialized prosthetic training and were tested again after 2 weeks (Training session). For sessions 3 through session 6, subjects were tested with a study socket and one of four randomized test feet. The test feet were SACH, SAFE, Talux and Proprio foot, classified as K1_foot, K2_foot, K3_foot and MP_foot, based on Medicare Functional Classification Level. The Step Watch Activity Monitor (SAM) recorded their daily activities in the 10-14 day accommodation period between two sessions. At each testing session, subjects completed the Prosthesis Evaluation Questionnaire (PEQ-13) and Usability questionnaire, and were evaluated using the Amputee Mobility Predictor (AMP) and the 6-minute walk test (6MWT). Ground reaction forces were collected using F-scan in-sole sensors as subjects performed the above mentioned functional activities. SEW values between the intact limb and the prosthetic limb were computed by integrating vertical ground reaction forces. Intra-class Correlation Coefficients (ICCs) were calculated to determine test-retest reliability and a repeated measure ANOVA was used to establish differences between the prosthetic feet. Results: The ICC values for Test-Retest reliability ranged from 0.84-0.94 for the various functional activities. There was moderate agreement between the SEW values calculated with F-scan and force plates. The SEW values were significantly different between the K3_foot and other feet during level walking and decline walking. During stair ascent, the MP_foot had a significantly higher SEW value than the other feet. There were no differences between feet during incline walking and stair descent. Training resulted in a significant improvement in symmetry from the Baseline session during sit-to-stand, while for stand-to-sit there were no differences between sessions. The PEQ-13 score was not different between sessions, while the Usability scores were significantly different between the K3_foot/MP_foot and K1_foot/K2_foot. The AMP score had a significant increase following Training while the 6MWT score showed a significant increase in the distance walked with the K1_foot, K3_foot and MP_foot over Baseline. The output of SAM did not show any difference in the number of steps or activity level of subjects. There was good to excellent correlation between the SEW values for level walking and other clinical outcome measures. Discussion and Conclusion: The SEW measure had excellent test-retest reliability and the agreement between the F-scan and force plates values could not be established because of a small sample size. The variations in SEW values were the result of distinctive designs of prosthetic feet. The high SEW value of the K3_foot can be attributed to its heel-toe foot plate and "J" shaped ankle spring design, which allowed for greater late stance stability. The active dorsiflexion feature of the MP_foot caused a change in strategy, typically used during stair ascent, resulting in a greater inter-limb symmetry. The SEW measure is a viable method to detect kinetic gait differences among prosthetic feet and represents a resource-effective alternative to traditional gait laboratories. It has several advantages and with further development of in-sole sensor technology, the potential for clinical use due to its relatively low cost instrumentation and minimal subject intervention.
47
Khatib, Ali. "A Comparison of Brain Trauma Characteristics from Head Impacts for Lightweight and Heavyweight Fighters in Professional Mixed Martial Arts." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39712.
Full textAbstract:
Athletes competing in the unarmed combat sport of mixed martial arts (MMA) are at an increased risk for long-term neurological consequences due to repetitive head trauma. Mass differentials as well as reported differences in fight styles between Lightweight and Heavyweight fighters in MMA may affect head impact kinematics creating different levels of head injury risk. Factors that influence the risk for head injury include the frequency, magnitude and interval of head impacts. The purpose of this study was to compare differences in frequency, frequency distribution of impact magnitudes, and time interval between head impacts per match between Lightweight and Heavyweight fighters in the Ultimate Fighting Championship (UFC). Head impacts of 60 fighters were documented from 15 Lightweight and 15 Heavyweight MMA fight videos. Impact type, frequency, and interval were recorded for each fighter, followed by the reconstruction of 345 exemplar impacts in the laboratory using a Hybrid III headform and finite element modeling to determine impact magnitudes. Next, head impacts (punches, kicks, knees and elbows) from fight videos were visually estimated to determine their corresponding magnitude range and establish the frequency distribution of impact magnitudes. The study revealed no significant differences in overall impact frequency and interval between Lightweight and Heavyweight fighters. The frequency distribution of different impact magnitudes was significantly different, with Lightweights sustaining significantly more Very Low, and High magnitude impacts. Overall, both Lightweight and Heavyweight MMA fighters sustain similar impact characteristics as other high-risk athletes including professional boxers and football players. Understanding the different factors that create brain trauma allows for the monitoring, identification, and protection of higher-risk athletes within these two weight classes.
48
Wernet, Jack R. "Comparison of the Statically Equivalent Serial Chain Center of Mass Estimation Method to OpenSim's Residual Reduction Algorithm." University of Dayton / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1628009554478147.
Full text
49
Sano, Takahiro. "Biomechanics of Fixation of Distal Radius Fractures: Comparison between Volar Plate Fixator (VPF) and Non-Bridging External Fixator (NBX)." Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_theses/121.
Full textAbstract:
Fracture of the distal radius is one of the most frequent injuries, and it represents about 20% of all adults taken into emergency rooms. A number of studies suggest various methods to reduce the dislocation and to secure fragments of the distal radius. In this study, the Non-Bridging External Wrist Fixator System (NBX), a pre-market-released product manufactured by NUTEK Inc. was biomechanically assessed by comparing with the Universal Distal Radius System (Volar Plate Fixator: VPF), a market-released product manufactured by Stryker Co. The comparison was performed in several parameters, which were wrist motion, radial tilt angle, radial length, volar tilt angle, stiffness, and failure load. Five pairs of fresh human cadaver arms were used for this study. The wrists were tested to obtain x-ray images for 1 normal and 2 injury conditions (intact, fractured, and fixed), 2 load conditions (gravity only and torque applied), and 4 postural conditions (volar flexion, dorsiflexion, ulnar deviation, and radial deviation). These tests yielded 24 (3×2×4) x-ray images for each wrist, and the images were analyzed to obtain the data for each parameter. Although the results were not statistically significant in some conditions, NBX fixation limited wrist motion more than VPF fixation. This result can be explained not only by the difference in the ability of fixation, but also by the difference in the surgical trauma (NBX is less invasive than VPF). Furthermore, in the measurement of radial tilt angle, radial length, and volar tilt angle, NBX was more effective than VPF to reduce and secure the bone fragments of the distal radius. In destructive test, the NBX is less strong than VPF. However, NBX is strong enough to sustain the expected forces of daily activity.
50
Deram, Aurélien. "Environnement générique pour la validation de simulations médicales." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENS022/document.
Full textAbstract:
Dans le cadre des simulations pour l'entrainement, le planning, ou l'aide per-opératoire aux gestes médicaux-chirurgicaux, de nombreux modèles ont été développés pour décrire le comportement mécanique des tissus mous. La vérification, la validation et l'évaluation sont des étapes cruciales en vue de l'acceptation clinique des résultats de simulation. Ces tâches, souvent basées sur des comparaisons avec des données expérimentales ou d'autres simulations, sont rendues difficiles par le nombre de techniques de modélisation existantes, le nombre d'hypothèses à considérer et la difficulté de réaliser des expériences réelles utilisables. Nous proposons un environnement de comparaison basé sur une analyse du processus de modélisation et une description générique des éléments constitutifs d'une simulation (e.g. géométrie, chargements, critère de stabilité) ainsi que des résultats (expérimentaux ou provenant d'une simulation). La description générique des simulations permet d'effectuer des comparaisons avec diverses techniques de modélisation (e.g. masse-ressorts, éléments finis) implémentées sur diverses plateformes de simulation. Les comparaisons peuvent être faites avec des expériences réelles, d'autres résultats de simulation ou d'anciennes versions du modèle grâce à la description commune des résultats, et s'appuient sur un ensemble de métriques pour quantifier la précision et la vitesse de calcul. La description des résultats permet également de faciliter l'échange d'expériences de validation. La pertinence de la méthode est montrée sur différentes expériences de validation et de comparaison de modèles. L'environnement et ensuite utilisé pour étudier l'influence des hypothèses de modélisations et des paramètres d'un modèle d'aspiration de tissu utilisé par un dispositif de caractérisation des lois de comportement. Cette étude permet de donner des pistes pour l'amélioration des prédictions du dispositifNumerous models have been developed to describe the mechanical behavior of soft tissues for medical simulation. Verification, validation and evaluation are crucial steps towards the acceptance of simulation results by clinicians. These tasks, often based on comparisons between simulation results and experimental data or other simulations, are difficult because of the wide range of available modeling techniques, the number of possible assumptions, and the difficulty to perform validation experiments. A comparison framework is proposed based on the analysis of the modelisation process and on a generic description of both constitutive elements of a simulation (e.g. geometry, loads, stability criterion) and results (from simulations or experiments). Generic description allows comparisons between different modeling techniques implemented in various simulation platforms. Comparisons can be performed against real experiments, other simulation results or previous versions of a model thanks to the generic description of results and use a set of metrics to quantify both accuracy and computational efficiency. This description also facilitates validation experiments sharing. The usability of the method is shown on several validation and comparison experiments. The framework is then used to investigate the influence of modeling assumptions and parameters in a biomechanical finite element model of an in-vivo tissue aspiration device. This study gives clues towards the improvement of the predictions of the characterization device