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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.
41

The effects of L4/5 fusion on the adjacent segments in the lumbar spine

Martinez Lozada, Francisco Mauricio January 2016 (has links)
Lumbar intervertebral disc disorder is a spinal condition that affects the normal function of the intervertebral discs mainly due to the natural aging process. This condition can manifest itself in pain and limited motion in the legs, amongst others. Posterolateral Fusion (PLF) and Posterior Lumbar Interbody Fusion (PLIF) are two of the most used surgical procedures for treating lumbar intervertebral disc disease. Although these procedures are commonly used and performed successfully the impact in terms of the stresses developed in the posterior implants employed and in the spinal components adjacent to the surgical site has not been exhaustively investigated. In addition, the consequences of the procedure on the reduction of the Range of Motion of the lumbar spine is not clearly understood. The objective of this research is to investigate the effect of one-level spinal fusion of lumbar segment L4-L5 on the stresses and the range of motion at the remaining, adjacent lumbar levels. Four 3 dimensional finite element models of a lumbosacral spine were created from Computer Tomography data (CT scan). The models were used to investigate four surgical scenarios, including the use of 0o and 4o interbody cages, in addition to the un-instrumented spine for flexion, extension, torsion and lateral bending motions. The predictions obtained from the models enabled the mechanical behaviour of the lumbar spine following fusion surgery using 0 o and 4o cages to be investigated and compared. In addition, a clinical study was performed to quantify the reduction in the range of motion for subjects who had undergone L4/5 posterior lumbar interbody fusion surgery. The clinical results were compared to those of subjects who had not undergone surgery and to the range of motion predictions from the computational model. The results from this research demonstrate that the insertion of posterior instrumentation does not have an impact on the spinal structures above the L3/4 intervertebral disc. However, the pedicle screws and the insertion of the interbody cages causes stress levels in the area adjacent to the surgical site to rise which could promote accelerated degeneration of the discs. Additionally, this study demonstrates how the pedicle screws are affected by the surgical spinal fusion techniques. Furthermore, the investigation demonstrates how posterior lumbar interbody fusion causes the range of motion of patients that had undergone this surgery to decrease. The results from the comparison of the behaviour of the use of 0º and 4º interbody cages in L4-5 posterolateral fusion demonstrates that the stress levels in the adjacent vertebrae, intervertebral discs and pedicle screw fixation system increase when 4º are used cages than when 0º cages were employed. The results from the in-vitro study show a decrease in the range of motion of the subjects who had undergone L4/5 posterior lumbar interbody fusion surgery when compared with the subjects with no low back pain history. This indicates that the PLIF surgery combined with the normal disc degeneration is subjected to higher stresses than the healthy spine.
42

The transmission of forces through animal joints

Greenwald, A. Seth January 1970 (has links)
No description available.
43

Calculation and Visualization of Range of Motion of Hip Joint from MRI

Aghayan, Sahar January 2014 (has links)
Femoro-Acetabular Impingement (FAI) is a hip joint disease which affects and impairs the range of hip motion during performing activities of daily living, jogging, walking, or climbing stairs due to the bony abnormalities of the joint. Ballet dancers and athletes (e.g. gymnasts and hockey players) put their hips at the risk of FAI by extremely moving the hip mainly by excessively rotating the joint. In this research, we introduce a visualization system which helps surgeons to analyze the range of hip motions as well as to have a better communication with patients. These goals are achieved by presenting three dimensional (3D) visualizations of motion envelope by examining the maximum possible rotation of the digital hip bones. Our computer simulation system estimates, analyzes and visualizes the maximum hip range of motion (ROM) for the constructed 3D bone models that are extracted from Magnetic Resonance Images (MRI) after segmenting the bones. These tasks are accomplished by first calculating Hip Joint Center (HJC) which is center of rotation of femoral head on the 3D segmented MRI models followed by simulating hip motions with examining impingement between the femur and the acetabulum using our collision detection system. In our collision detection system, surfaces of femoral head and acetabulum bones are sampled in the spherical coordinates based on rasterization and interpolation. Then, the distance between the femoral head and acetabulum are computed to prevent impingement between them. The maximum motion degree of femur bone within depression of acetabulum in every direction during the digital simulation shows the ROMs of the inputted MRI of the hip joint. Six primary plane motions (flexion/extension, abduction/adduction and internal/external rotation) as well as various combinations of these motions (maximum rotation of the hip between every two rotational movements) and successive movements (maximum rotational movement of the hip per another rotational movement) are simulated and analyzed along with 3D visualization of estimated range of these motions. Generally, the ROM differs by some factors such as age, gender, ethnicity, and geographic location. For instance, newborns up to age two have considerably greater motion in hip flexion and hip abduction than adults. Our system by 3D visualization of motion envelope will provide a platform to understand quicker and better the effect of bony morphology of the hip joint on the possible ROM. We also examine the long-standing question about moving center of rotation related to ROM. We found out the ROM becomes bigger especially when the center moves outward to the direction of acetabulum axis. This thesis does not consider the effect of muscle and other surrounding connective tissue on the hip ROM since they can be altered significantly by physical training to show the potential of maximum ROM. For example a ballerina has a bigger ROM leading a bigger motion envelope compared with non-dancers. Hence we visualize the range of joint motions and their envelopes that are obtained from the osseous anatomy of the hip joint. The osseous anatomy of the joint is the most fundamental and permanent factor of ROM which indicates the maximum motion that the joint can achieve if the muscle and other connective tissues are perfectly trained.
44

Hodnocení rozsahu pohybu horních končetin pomocí programu OpenPose / Evaluation of the range of motion of the upper limbs using the OpenPose program

Sýkorová, Michaela January 2021 (has links)
Title: Evaluation of the range of motion of the upper limbs using the OpenPose program Objectives: The aim of the work was to determine whether it is possible to use the OpenPose program as a tool for measuring upper limb range of motion, highlight OpenPose limits and consider whether the program could be used for evaluation in clinical practise or as part of telerehabiliation in the future. Methods: 48 probands participated in the research. Participants were intentionally selected from healthy population due to the nature of the work. Each participant was measured in 6 different positions while lying on a lounger. Measurements were taken bilaterally. A total of 14 different angles of shoulder and elbow were measured. These were maximum flexion of the elbow joint, flexion of the arm with flexion of the elbow, flexion of the arm, internal and external rotation of the arm and extension of the arm. Data were collected using a standardised examination method using a goniometer and a video recording. Video recordings were later used in the OpenPose program for angle evaluation. Finally, the results of both methods were compared. Results: 8 out of total 14 measured angles of shoulder and elbow were excluded based on evaluation criteria. Values with average difference between both examiner's results...
45

Betydelse av variabeln rörelseomfång inom styrketräningsvolym : en studie av dess inverkan på återhämtning av kraftutveckling

Forsberg, Linus January 2022 (has links)
Syfte &amp; Frågeställning: Syftet är att studera hur manipulering av ROM påverkar två olika träningsprogram med samma mängd träningsvolym (sets x reps x vikt x tid). Syftet är specifikt att studera hur ROM kan påverka ansträngningsgraden, prestationen i form av kraftutveckling under återhämtningsperioden, men även en uppskattning på träningsvärk av dessa två träningsprogram och på så sätt estimera betydelsen av ROM.  Frågeställningar: I ett träningsupplägg i en benspark med fullt respektive partiellt ROM. Påverkas kraftutvecklingen i en statisk knäböj, upplevd ansträngning under bensparken samt graden av träningsvärk från baslinje, 24 och 48 timmar senare trots likvärdig träningsvolym.? Metod: Detta är en kvantitativ experimentell studie som sex personer deltog i. Effekten av två olika träningsprogram, ett för vardera ben, undersöktes genom att mäta kraftutveckling genom statisk knäböj före träningsprogrammet (vid baslinje) och 24 timmar efter träningsprogrammet. Ett ben genomförde fullt ROM medan det andra benet genomförde partiellt ROM. Under träningspasset angav deltagarna graden av muskulär ansträngning med hjälp av en subjektiv ansträngningsskala efter set 4 och set 8. Innan styrketräningen genomförde deltagarna en knäböj med ett ben under vilken graden av muskulär värk angavs vid baslinjen, samt efter 24 och 48 timmar från baslinjen. Resultat: Resultatet visar inte på någon signifikant skillnad mellan fullt och partiellt ROM vad gäller kraftutvecklingen i en statisk knäböj vid jämförelsen mellan baslinje och 24 timmar senare. En signifikant skillnad kunde ses vid ansträngningsgraden vid genomförandet i bensparken mellan fullt ROM 17,75±0,88 och partiellt ROM 14,00±1,26 efter 8 set (P &lt;0.05). Vid självupplevd smärtskattning resulterades en signifikant skillnad efter 24 och 48 timmar efter styrketestet mellan fullt ROM 30,8±21,3 och partiellt ROM 20,5±14. Slutsats: Resultatet från träningen visar att fullt ROM är mer ansträngande, orsakar mer träningsvärk samt tenderar till att sänka kraftutveckling i benmuskulaturen vid återhämtningen jämfört med träning med partiellt ROM. / <p>Ämneslärarprogrammet, Specialidrott</p>
46

Stretching: Acute and Chronic? the Potential Consequences

Stone, Mike, Ramsey, Michael W., Kinser, Ann M., O'Bryant, Harold S., Ayers, Chris, Sands, William A. 01 January 2006 (has links)
Stretching is commonly used by many athletes in different sports. Although acute stretching, as part of a warm-up, can enhance range of motion, it may also reduce performance. Acute stretching can reduce peak force, rate of force production, and power output. Chronic stretching may enhance performance, although the mechanism is unclear. Acute stretching has little effect on injury. However, chronic stretching (not part of warm-up) may have some injury reduction potential.
47

Validation Of A Smartphone Application For Measuring Shoulder Internal Rotation and External Rotation Range Of Motion With Intra-Rater Reliability

Smith, Allison B., Smith January 2016 (has links)
No description available.
48

Coordination of multiple muscles in two degree of freedom elbow movements

Sergio, Lauren E. (Lauren Elisabeth) January 1994 (has links)
No description available.
49

System identification of human ankle muscles activation dynamics

Génadry, Walid François. January 1986 (has links)
No description available.
50

Consequence of Functioning at the End Range of Joint Motion: Implications on Anterior Knee Pain

Rodrigues, Pedro A 13 May 2011 (has links)
“Excessive” and/or “delayed” subtalar joint (STJ) pronation has been linked to overuse injuries because of its influence on tibial internal rotation (TIR). The transfer of STJ pronation to TIR occurs via the talocrual joint, believed to have limited transverse plane motion. However, studies have shown the talocrural joint to have more transverse plane motion than once believed, therefore it is feasible that the STJ will only influence the motion of the tibia once this motion has been exhausted. Currently, studies evaluating this relationship have focused on peak joint angles and excursion without reference to the amount of motion available at the ankle joint complex (AJC). Therefore the purpose of these studies were to evaluate whether runners with anterior knee pain (AKP) utilize a greater percentage of their available eversion motion (eversion buffer), evaluate the effects of small eversion buffers on coordination, and evaluate the influence of orthotics on those with AKP and with the smallest eversion buffers. This study found healthy and injured runners, for the most part, presented with no significant differences in traditional pronation related variables. The one exception was peak pronation velocity, where injured runners demonstrated faster velocities. On the other hand injured runners had significantly smaller eversion buffers which lead them to change their coordinative pattern earlier during stance. This difference in pattern also caused the intra-individual coupling variability to peak earlier during stance. Orthotics successfully controlled the kinematics of the AJC and increased the eversion buffer of injured runners and in those displaying the smallest buffers. While orthotics successfully influenced the kinematics of the AJC, they did not influence those of the tibia and knee. These changes at the AJC did not have a strong impact on the coordinative patterns of the lower extremity, however demonstrated a trend toward being able to influence the intra-individual coupling variability. In summary, injured runners demonstrated smaller eversion buffers and changed their coordinative pattern earlier during stance. While orthotics successfully increased the eversion buffer, they did not strongly influence coordination variables. Future studies analyzing pronation related variables in injured populations should evaluate them relative to the available motion at the AJC.

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