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Articles 1 - 30 of 80
Full-Text Articles in Engineering
Development Of Four-Dimensional Computed Tomography Based Methods To Measure Shoulder Kinematics In Healthy Individuals And In Patients Following Total Shoulder Arthroplasty, James Hunter
Electronic Thesis and Dissertation Repository
Dynamic kinematics of the shoulder, particularly the interplay between the glenohumeral and scapulothoracic joints and the changes associated with aging, remain not fully understood. Current research often focuses on simple motions, neglecting more complex movements common in activities of daily living, such as internal rotation to reach behind the back. Post-total shoulder arthroplasty (TSA) surgery, many patients experience difficulties with internal rotation, affecting tasks like dressing and bathing. This dissertation employs four-dimensional computed tomography (4DCT) to enhance understanding of shoulder biomechanics and TSA outcomes by assessing dynamic shoulder kinematics in a healthy population and a post-implant population.
The first objective …
A Pilot Study Comparing Muscle Activation And Kinematic Parameters Between Professional And Non-Professional Tennis Players, Anton S. Petrenko
A Pilot Study Comparing Muscle Activation And Kinematic Parameters Between Professional And Non-Professional Tennis Players, Anton S. Petrenko
Masters Theses
Tennis, a widely played sport across various age and skill groups, prompts continual skill improvement among competitive players seeking a competitive edge. This study explores two approaches for enhancing playing style: motion capture (MoCap) and surface electromyographic (sEMG) signals. The study addresses a gap in simultaneous examination of MoCap and entire dominant leg muscle activation, particularly concerning the influence of skill level and gender on various tennis strokes. To fill this void, the research records and analyzes MoCap and dominant leg sEMG data during serves and strokes on both court sides. The hypothesis posits differences in muscle activation and body …
Advances In Bone And Orthopedics 2024 Edition, Jean-Philippe Berteau, Laurent Pujo-Menjouet
Advances In Bone And Orthopedics 2024 Edition, Jean-Philippe Berteau, Laurent Pujo-Menjouet
Publications and Research
We are delighted to present the latest edition of ”Advances in Bone and Orthopedics,” a comprehensive compilation of pioneering research and innovative developments in the field. This volume brings together a selection of peer-reviewed abstracts from BONITOS 2024, the Fourth Season of the Bone and Orthopedics Interdisciplinary Symposium, held on May 31st, 2024, at the College of Staten Island in New York. This symposium, a hallmark event in the calendar of professionals dedicated to bone health and orthopedic excellence. The contributions within this volume reflect the breadth and depth of research presented at BONITOS 2024. These abstracts represent cutting-edge studies …
The Development And Enhancement Of A Forward Mathematical Model Of The Human Knee Joint, Seth Coomer
The Development And Enhancement Of A Forward Mathematical Model Of The Human Knee Joint, Seth Coomer
Doctoral Dissertations
Degenerative joint disease, or osteoarthritis, is a common occurrence in the knee joint. This can often result in joint pain, decrease in range of motion, and ultimately disability. One way to counteract osteoarthritis is the incorporation of a total knee arthroplasty (TKA). TKAs replace the damaged bone and soft tissue surrounding the knee with metal and polyethylene components. Ideally this will improve the joint’s performance and reduce pain. However, there is still a number of TKA patients who remain dissatisfied. In order to investigate this, in depth research must be done on the design and performance of TKAs.
One such …
Motor Control Quantification And Necessary Improvements For Individuals With Post-Stroke Gait: Implications For Future Customizable Rehabilitation Approaches, Azarang Asadi
Doctoral Dissertations
Although often taken for granted, walking is an extremely complex motor skill that requires sensory inputs, neural communication, advanced control strategies, and coordination of the muscles and joints. Electrical signals traveling from the brain to the muscles are transformed to mechanical forces to achieve desired motion. A stroke damages the central nervous system and neural pathways, limiting the ability of survivors to walk. Walking speed is significantly decreased and asymmetrical walking patterns emerge. A crucial component of stroke rehabilitation is gait training, a therapeutic intervention to help individuals to improve their walking ability, as walking is essential for functional independence …
Digital Twins Of The Living Knee: From Measurements To Model, Thor Erik Andreassen
Digital Twins Of The Living Knee: From Measurements To Model, Thor Erik Andreassen
Electronic Theses and Dissertations
Modern medicine has dramatically improved the lives of many. In orthopaedics, robotic surgery has given clinicians superior accuracy when performing interventions over conventional methods. Nevertheless, while these and many other methods are available to ensure treatments are performed successfully, far fewer methods exist to predict the proper treatment option for a given person. Clinicians are forced to categorize individuals, choosing the best treatment on “average.” However, many individuals differ significantly from the “average” person, for which many of these treatments are designed. Going forward, a method of testing, evaluating, and predicting different treatment options' short- and long-term effects on an …
Computational Methodology For Generating Patient-Specific Soft Tissue Representations, Ahilan Anantha Krishnan
Computational Methodology For Generating Patient-Specific Soft Tissue Representations, Ahilan Anantha Krishnan
Electronic Theses and Dissertations
This dissertation focused on modeling specimen-specific soft tissue structures in the context of joint replacement surgery. The research addressed four key aspects. The first study involved developing a workflow for creating finite element models of the hip capsule to replicate its torque-rotational response. Experimental data from ten cadaveric hips were used to calibrate the models, resulting in improved accuracy and relevance for surgical planning and implant design. The second study tackled the challenge of expediting the calibration of mechanical properties of the hip capsule to match patient-specific laxities. A statistical shape function model was proposed to generate patient-specific finite element …
Patient Movement Monitoring Based On Imu And Deep Learning, Mohsen Sharifi Renani
Patient Movement Monitoring Based On Imu And Deep Learning, Mohsen Sharifi Renani
Electronic Theses and Dissertations
Osteoarthritis (OA) is the leading cause of disability among the aging population in the United States and is frequently treated by replacing deteriorated joints with metal and plastic components. Developing better quantitative measures of movement quality to track patients longitudinally in their own homes would enable personalized treatment plans and hasten the advancement of promising new interventions. Wearable sensors and machine learning used to quantify patient movement could revolutionize the diagnosis and treatment of movement disorders. The purpose of this dissertation was to overcome technical challenges associated with the use of wearable sensors, specifically Inertial Measurement Units (IMUs), as a …
Effect Of Amputation On Muscle Structure Properties In A Rabbit Model, Roy Caleb Stubbs
Effect Of Amputation On Muscle Structure Properties In A Rabbit Model, Roy Caleb Stubbs
Masters Theses
After amputation, muscles in the residual limb are detached from their insertion points and no longer span the missing joints. Our objective was to quantify the effect of amputation-induced disuse on residual muscle structure, an indirect indicator of muscle force-generating capacity. One hind paw was surgically removed at the ankle joint of ten rabbits. At two weeks (n=5) and 4 weeks (n=5) post-amputation and for select muscles (gastrocnemius, soleus, tibialis cranialis, extensor digitorum, and flexor digitorum superficialis), we measured and computed several muscle structure properties. Additionally, we qualitatively assessed the muscle fiber appearance of histological samples at each timepoint. At …
Mitral Valve Imaging And Biomechanics: A Workflow Towards Computational Modeling And Validation, Sam Stephens
Mitral Valve Imaging And Biomechanics: A Workflow Towards Computational Modeling And Validation, Sam Stephens
Graduate Theses and Dissertations
The mitral valve serves a critical role in healthy cardiac function by ensuring the unidirectional flow of oxygenated blood from the left atrium into the left ventricle. It experiences the highest pressures found within the heart and its closure is the result of a complex interaction of several different structures that, furthermore, are unique to each individual. Despite the valve’s vital role however, the specific function of these constituent structures is not fully understood. This, confounded by its asymmetric, personalized nature, make surgical interventions for the mitral valve far less effective than for its neighboring aortic valve. Efforts to overcome …
Quantifying Fibronectin Mechanical Properties Using Antibody-Mediated Optical Tweezing (Amot), Caleb Dalton
Quantifying Fibronectin Mechanical Properties Using Antibody-Mediated Optical Tweezing (Amot), Caleb Dalton
Theses and Dissertations
Despite decades of investigations into fibronectin (FN) fibrillogenesis, fibril mechanics remain unclear. One of the most important roles for FN fibrils is in the arena of cellular mechanotransduction. Numerous studies have demonstrated that cells sense and respond to the mechanical properties of their surroundings; since FN fibrils are a major constituent of the ECM that links cells to their surroundings, mechanotransduction cannot be fully understood without understanding the mechanical properties of FN fibrils. In this proposal, a novel biomechanical assay is developed to probe isolated FN fibrils and quantify their response to specific loading conditions. This will be accomplished by …
Making Sense Of Big (Kinematic) Data: A Comprehensive Analysis Of Movement Parameters In A Diverse Population, Naomi Wilma Nunis
Making Sense Of Big (Kinematic) Data: A Comprehensive Analysis Of Movement Parameters In A Diverse Population, Naomi Wilma Nunis
University of the Pacific Theses and Dissertations
OBJECTIVE
The purpose of this study was to determine how kinematic, big data can be evaluated using computational, comprehensive analysis of movement parameters in a diverse population.
METHODS
Retrospective data was collected, cleaned, and reviewed for further analysis of biomechanical movement in an active population using 3D collinear resistance loads. The active sample of the population involved in the study ranged from age 7 to 82 years old and respectively identified as active in 13 different sports. Moreover, a series of exercises were conducted by each participant across multiple sessions. Exercises were measured and recorded based on 6 distinct biometric …
Recent Advances In Bone Research 2022 Edition, Jean-Philippe Berteau, Laurent Pujo-Menjouet
Recent Advances In Bone Research 2022 Edition, Jean-Philippe Berteau, Laurent Pujo-Menjouet
Publications and Research
More and more scientific and engineering applications in bone research make pivotal advances in treating patients with orthopedics issues. Hence, bone research in the 21st century combines, inter alia, biology, chemistry, mathematics, and mechanics with complementary characteristics that help a holistic approach to bone-related pathologies. Nowadays, it is hard to connect new evidence when jargoning and money remain two significant obstacles to sharing knowledge. “Recent Advances In Bone Research” is a free book – no money involved at any stage - that combines the most recent efforts in bone research from several experts with different backgrounds, every expert seeks to …
A Novel Ultrasound Elastography Technique For Evaluating Tumor Response To Neoadjuvant Chemotherapy In Patients With Locally Advanced Breast Cancer, Niusha Kheirkhah
A Novel Ultrasound Elastography Technique For Evaluating Tumor Response To Neoadjuvant Chemotherapy In Patients With Locally Advanced Breast Cancer, Niusha Kheirkhah
Electronic Thesis and Dissertation Repository
Breast cancer is the second most diagnosed cancer in women, estimated to affect 1 in 8 women during their lifetime. About 10% to 20% of new breast cancer cases are diagnosed with locally advanced breast cancer (LABC). LABC tumors are usually larger than 5 cm and/or attached to the skin or chest wall. It has been reported that when such cases are treated with surgery alone, metastasis and mortality rates are high, especially where skin involvement or attachment to the chest wall is extensive. As such, efficient treatment for this kind of breast cancer includes neoadjuvant chemotherapy (NAC) to shrink …
Biomechanical Analysis Of Athletes Sprinting With Varying Degrees Of Resistance, Michaela Ott
Biomechanical Analysis Of Athletes Sprinting With Varying Degrees Of Resistance, Michaela Ott
Honors Theses
Utilizing resistance methods for sprinters is a common approach to their training. In this study, six athletes from the University of Nebraska-Lincoln Women’s Track and Field Team ran a series of sprints using a resistance machine to collect data regarding the change in power output, stride length, level of trunk tilt with respect to the ground, and acceleration throughout a distance of ten meters when different amounts of resistant forces were applied to the athlete. It was hypothesized that as resistance increased, power output would increase, stride length would decrease, the runners would become more horizontal resulting in a larger …
Youth Pitching Kinematics: Associations With Body Overweight Parameters, Christina K. Fong
Youth Pitching Kinematics: Associations With Body Overweight Parameters, Christina K. Fong
Master's Theses
The objective of this study was to investigate associations between injury-related kinematic parameters and overweight measures for youth baseball pitchers. The injury-related kinematic parameters considered were measurements 1) at foot contact: stride length, front foot position, shoulder external rotation, shoulder abduction, and elbow flexion; 2) between FC and ball release: peak knee extension; and 3) at BR: shoulder abduction. Data from three separate collection sites examined pitching mechanics of 18 10- to 11-year-old pitchers, 11 14- to 16-year-old pitchers, and 104 16- to 18-year-old pitchers Linear regression analyses were performed to determine significant correlations between kinematic parameters and body mass …
Effect Of Viscoelasticity On Cellular Morphology And Activity, Thomas J. Petet Jr
Effect Of Viscoelasticity On Cellular Morphology And Activity, Thomas J. Petet Jr
Theses and Dissertations
It has been well established that there is a link between substrate stiffness and cellular activities such as proliferation, migration, and differentiation. Less characterized is the link between the time-dependent viscosity of a substrate with those cellular activities. To explore this, PDMS substrates were created with predictably tunable stiffness and viscosity parameters. A simulated model was also developed in parallel to explore the potential effects of viscosity in a computationally predictive way. It was found that the inclusion of viscosity caused a major paradigm shift to a non-zero substrate equilibrium that was sensitive to increases in the substrate stiffness. Finally, …
An Investigation Into The Plate Fixation For Periprosthetic Femoral Fractures, Xiang Chen
An Investigation Into The Plate Fixation For Periprosthetic Femoral Fractures, Xiang Chen
Electronic Theses and Dissertations
Periprosthetic femoral fractures are the third most reason for reoperation after the total hip arthroplasty with an incident rate of approximately 6%. The Vancouver type B periprosthetic femoral fractures account for over 70% of all cases, while the sub-type B1 fracture (when the total hip stem is stable) has remained a clinical challenge due to incidences of severe complications after the standard plate-screw fixation. To seek biomechanically sound fixations for the Vancouver type B1 fracture, this dissertation developed a combined modeling and testing framework to investigate the efficacy of fixation for a Vancouver type B1 fracture using different construct lengths …
Characterizing Locomotor Disturbance Perception In Young Adults, Daniel James Liss
Characterizing Locomotor Disturbance Perception In Young Adults, Daniel James Liss
Graduate Theses, Dissertations, and Problem Reports
Falls during walking are a leading cause of injuries across aging. Many of these falls are due to slips and trips. The ability to perceive disturbances to ongoing motion may play an important role in the control of walking balance. However, disturbance perception has been investigated in standing balance, but its role in walking balance due to slip- and trip-like disturbances remains largely unknown. Characterizing locomotor disturbance perception in young adults may lead to a more comprehensive understanding of sensorimotor walking balance control.
This work defined locomotor disturbance perception in response to slip and trip-like disturbances in young adults. We …
Multi-Task Neuromuscular Generalization And Changes Through The Lifespan, Hannah Delaney Carey
Multi-Task Neuromuscular Generalization And Changes Through The Lifespan, Hannah Delaney Carey
Graduate Theses, Dissertations, and Problem Reports
Mobility in everyday life requires executing and shifting between a broad assortment of functional tasks and resisting disturbances that could cause falls. Though the importance of successfully performing a variety of functional tasks is recognized and incorporated in clinical assessments (e.g., the Timed-Up-and-Go Test, Berg Balance Scale), little is understood about the underlying neuromuscular control required, or how it changes with age. The neuromuscular control for functional tasks such as walking is typically studied in isolation, or with variations on the same task. Characterizing the coordination required to produce and shift between a wider variety of tasks and resist external …
Collision Tracking And Brain Mapping, Carl Russell Iii
Collision Tracking And Brain Mapping, Carl Russell Iii
The Journal of Purdue Undergraduate Research
No abstract provided.
Quantifying The Effect Of Intrinsic Aging On Skin Microstructure And Mechanical Function Using Multiphoton Microscopy, Alan Edward Woessner
Quantifying The Effect Of Intrinsic Aging On Skin Microstructure And Mechanical Function Using Multiphoton Microscopy, Alan Edward Woessner
Graduate Theses and Dissertations
Over the next couple of decades, the number of elderly individuals is expected to double, bringing increased healthcare spending due to seemingly minor injuries to skin. In skin, the 3D dermal collagen fiber network, which is the primary load-bearing structure, undergoes changes in organization and composition due to intrinsic aging. However, the relationships between altered microstructure and mechanical function is not well understood. Quantitative imaging techniques have been used in the past to link skin structure to mechanical function, but previous analysis has been limited to 2D assessments. Multiphoton microscopy (MPM) is a non-destructive imaging technique with intrinsic depth-sectioning capabilities, …
Drive Leg And Stride Leg Ground Reaction Forces Relationship To Medial Elbow Stress And Velocity In Collegiate Baseball Pitchers, Brett Smith
Biomedical Engineering Theses & Dissertations
This study examines several different kinetic variables in relation to pitch velocity and elbow varus torque in collegiate baseball pitchers using force plates, an inertial measurement unit, and a radar unit. The purpose of this study is to investigate the kinetic variables being measured and their relationship to pitch velocity and loads being placed on the medial elbow. Twelve collegiate baseball pitchers participated in this study, which was approved by the IRB. Impulse of the drive leg in the anterior-posterior direction, stride leg peak force in the anterior-posterior (AP) direction, elbow varus torque, and pitch velocity were all measured. Two …
In Vitro Analyses Of The Contributions Of The Hip Capsule To Joint Biomechanics, Emma Donnelly
In Vitro Analyses Of The Contributions Of The Hip Capsule To Joint Biomechanics, Emma Donnelly
Electronic Thesis and Dissertation Repository
Optimal management of the hip capsule during arthroscopic surgery has not been established. The impact of incisions made to the capsule during minimally invasive procedures on joint biomechanics, and whether repair provides any benefit, continue to be debated. The effectiveness of capsular repair to restore native kinematics may be insufficient. Therefore, a better understanding of joint behavior during various capsule conditions is needed. A new robotic system was used to analyze the effect of progressive capsulotomy incision and repairs on the behavior of a normal hip within range of motion (ROM) limits with respect to the intact joint. Complete repairs …
Feasibility Study To Measure The Impact Of A Specialized Core Exercise On Metabolic Efficiency And Stability During Walking For Above Knee Amputees, Shaye M. Tiell, Sabrina R. Segretario, Serena M. Myers, Emily G. Tully
Feasibility Study To Measure The Impact Of A Specialized Core Exercise On Metabolic Efficiency And Stability During Walking For Above Knee Amputees, Shaye M. Tiell, Sabrina R. Segretario, Serena M. Myers, Emily G. Tully
Williams Honors College, Honors Research Projects
The objective of this study is to determine the feasibility of improving the gait of above-knee (AK) amputees by performing daily core exercises aimed to provide an efficient and stable walking pattern. The goal of the exercise is to strengthen core muscles and form temporary neural connections in the brain aimed at improving metabolic efficiency and stability. We will be implementing the Wright Balance Core 360 Exercise Technique for completion by our subjects. Motion capture technology will be utilized in conjunction with a metabolic oxygen consumption analyzer to collect stability and metabolic efficiency data while amputees walk on a treadmill. …
Dislocation Mechanics Of Total Hip Arthroplasty: A Combined Experimental And Computational Analysis, Michael Scinto
Dislocation Mechanics Of Total Hip Arthroplasty: A Combined Experimental And Computational Analysis, Michael Scinto
Electronic Theses and Dissertations
While total hip arthroplasty is considered a successful procedure, dislocation remains a serious complication as recurrent dislocations may require additional surgeries. Knowledge on dislocation events as they occur in vivo are limited, therefore researchers rely on experimental and computational methods. A custom MATLAB script and an experimental procedure utilizing a six-degree of freedom actuator were developed to further understand how various surgical considerations affect dislocation mechanics in total hip arthroplasty. Computationally, it was determined that impingement free range of motion is limited during internal rotation in flexion and during external rotation in extension. Experimentally, our results suggest that the posterior …
Smartphone-Tape Method For Calculating Body Segment Inertial Parameters For Analysis Of Pitching Arm Kinetics, Jay Sterner
Smartphone-Tape Method For Calculating Body Segment Inertial Parameters For Analysis Of Pitching Arm Kinetics, Jay Sterner
Master's Theses
The objectives of this study were to (1) develop a non-invasive method (referred to as Smart Photo-Tape) to calculate participant-specific upper arm, forearm, and hand segment inertial properties (SIPs) (e.g. mass, center of mass, and radii of gyration) and (2) use those Smart Photo-Tape properties in inverse dynamics (ID) analyses to calculate injury-related pitching arm kinetics. Five 20- to 23- year-old baseball pitchers were photographed holding a baseball and analyzed using the Smart Photo-Tape method to obtain 3-D inertial properties for their upper arm, forearm, and hand. The upper arm and forearm segments were modelled as stacked elliptic cylinders and …
Atv Dynamics And Pediatric Rider Safety, James T. Auxier Ii
Atv Dynamics And Pediatric Rider Safety, James T. Auxier Ii
Theses and Dissertations--Biomedical Engineering
It has been observed through numerous academic and governmental agency studies that pediatric all-terrain vehicle ridership carries significant risk of injury and death. While no doubt valuable to safety, the post-hoc approach employed in these studies does little to explain the why and how behind the risk factors. Furthermore, there has been no prolonged, widespread, organized, and concerted effort to reconstruct and catalog the details and causes of the large (20,000+) number of ATV-related injuries that occur each year as has been done for road-based motor vehicle accidents. This dissertation takes the opposite approach from a meta-analysis and instead examines …
The Effect Of Implant Conformity On Muscle Force Requirements In The Implanted Knee, Grace Mcconnochie
The Effect Of Implant Conformity On Muscle Force Requirements In The Implanted Knee, Grace Mcconnochie
Boise State University Theses and Dissertations
Implant geometry is a significant factor in determining knee stability and patient satisfaction following total knee replacement (TKR). Ineffective muscle recruitment, impaired joint functionality and increased implant wear are consequences of an unstable knee replacement. Current knee laxity evaluation techniques are limited in their ability to account for the muscular response to knee instability. This study utilizes a subject specific lower-body musculoskeletal finite element (FE) model with dynamic muscle loading to evaluate implant laxity during activities of daily living. The effect of varying implant conformity on the muscle forces required to maintain a target kinematic profile during simulated laxity testing …
Role Of Angiotensin I And Ii On The Tissue Mechanics Of The Aortic Heart Valve Via Receptor Binding And Converting Enzymes, Josh Fahy
Biomedical Engineering Undergraduate Honors Theses
The renin-angiotensin system (RAS) plays a crucial role in the regulation of renal, cardiac, and vascular physiology. This system regulates in vivo blood pressure and fluid balance. As renal blood flow decreases, the kidneys convert prorenin into renin and secrete it into the circulatory system. Renin then converts angiotensinogen into angiotensin I (ang-I). The ang-I is then converted into angiotensin II (ang-II) by the angiotensin-converting enzyme (ACE). Ang-II, a vasoconstrictor, increases blood pressure by causing the blood vessels to narrow. Recent evidence suggests that RAS may be involved in the progression of valve disease, most notably, aortic stenosis.
The first …