Biomechanics Commons^™

Advancing Tka Biomechanics: From Joint Simulator To Boundary Condition Development, Yashar Ali Behnam

Electronic Theses and Dissertations

This dissertation addresses four specific aims that collectively attempted to advance the experimental and computational analysis of total knee arthroplasty (TKA) components. The first study focused on the development of a novel whole knee joint simulator capable of simultaneous tibiofemoral and patellofemoral knee loading. This simulator employs custom fixturing to facilitate dynamic, unconstrained, muscle-driven PF articulation alongside controlled TF contact mechanics. Validation against experimental measurements showed strong agreement, demonstrating the simulator's potential as a valuable tool for future TKA design and surgical technique investigations.

The second study verified implant-specific physiological boundary conditions which accurately simulate activities of daily living using …

Air-Jet Bioprinting Of Stem Cell-Encapsulated Alginate Micro-Droplets For Organoid Biomanufacturing, Mirabella B. Stump

Electronic Theses and Dissertations

Biomanufactured 3D-organoids show promise for modeling and treating various conditions, particularly insulin-dependent diabetes mellitus (type-1 diabetes). Pancreatic islet organoids serve as sustainable sources of insulin-producing β-cells, potentially restoring insulin regulation in patients and providing a long-term solution for diabetes. Hydrogel droplet printing is an emerging technique in regenerative medicine due to its advantageous tunability and biocompatibility; however, challenges of consistency, quality control, and scalability persist. To address these issues, we developed a novel air-jetting based droplet bioprinting system for the generation of monodispersed alginate micro-droplets. The objective of this project was to incorporate human induced pluripotent stem cells (hiPSCs) into …

Kinematic Analysis Of Gait And Deep Knee Flexion For Pre- And Post-Operative Total Knee Arthroplasty, Samantha Collins

Electronic Theses and Dissertations

Osteoarthritis (OA) is a form of arthritis that develops in the joint due to overuse and aging causing pain, discomfort, and disability. Total Knee Arthroplasty (TKA) is a surgical procedure performed when OA symptoms are severe with an estimated 600,000 patients in the United States currently receiving TKA. Studies have reported dissatisfaction of the knee for 14-39% of patients. This study collected knee kinematics before and after surgery using stereo radiography for precise measurement of gait and deep knee flexion activities. Results showed healthy knee kinematics were not restored and no significant changes could be seen from OA kinematics in …

Exploration Of Motion Capture System To Investigate Human Shoulder Kinematics, Ola Alsaadi

Electronic Theses and Dissertations

The glenohumeral joint (GH) is commonly conceptualized as a ball-and-socket joint [1], and its center of rotation (COR) is presumed to coincide with the geometric center of the medial-superior region of the humeral head [2]. Recent research has endorsed improvements in COR estimation through invasive and noninvasive techniques, including cadaver studies, stereophotogrammetry, and motion capture (MOCAP) systems. Despite increased interest in wearable technology within human movement analysis, the problem of COR estimation employing MOCAP systems and its validation against bi-planar fluoroscopy remains relatively unexplored.

This study employed a marker-based MOCAP system to compare the accuracy, error, and precision of three …

Acute Responses To Combined Accentuated Eccentric Loading And Rest Redistribution, Sungwon Chae

Electronic Theses and Dissertations

This dissertation was 2 parts of investigations of various acute responses to high-volume combined accentuated eccentric loading and rest redistribution (AEL + RR). Resistance-trained men (n = 12, 25.6 ± 4.4 years, 1.77 ± 0.06 m, 81.7 ± 11.4 kg) completed a back squat (BS) 1 repetition maximum (1RM) and weight releaser familiarization session. Three BS exercise conditions (sets × repetitions × eccentric/concentric loading) comprised AEL + RR 5: 3 × (5 × 2) × 110/60%, AEL + RR 2: 3 × (2 × 5) × 110/60%, and traditional sets (TS): 3 × (1 × 10) × 60/60% 1RM. The …

Novel Approach For Non-Invasive Prediction Of Body Shape And Habitus, Emma Young

Electronic Theses and Dissertations

While marker-based motion capture remains the gold standard in measuring human movement, accuracy is influenced by soft-tissue artifacts, particularly for subjects with high body mass index (BMI) where markers are not placed close to the underlying bone. Obesity influences joint loads and motion patterns, and BMI may not be sufficient to capture the distribution of a subject’s weight or to differentiate differences between subjects. Subjects in need of a joint replacement are more likely to have mobility issues or pain, which prevents exercise. Obesity also increases the likelihood of needing a total joint replacement. Accurate movement data for subjects with …

Tibial Strains And Tray-Bone Micromotions After Total Knee Arthroplasty: Computational Studies Evaluating The Tibial Fixation, Huizhou Yang

Electronic Theses and Dissertations

Cemented and cementless fixation in total knee arthroplasty (TKA) have been successfully used for decades. As the number of younger and more active patients treated with TKA continues to increase, long-term implant survivorship is of increasing importance. One of the most common complications and hence the reason for revision is mechanical loosening (23.1% of all revised TKA). The loosening mechanisms have been proposed for different fixation types. For cemented fixation, bone remodeling after surgery is regulated by the changes in strain energy density (SED). The recruitment of osteoclasts and osteoblasts is controlled by SED-related signals. Insufficient stimuli can promote bone …

Accurate Measurement Of Healthy Joint Kinematics To Inform Diagnosis And Treatment, Vasiliki Kefala

Electronic Theses and Dissertations

The description of human motion has a primary importance in different scientific areas such as medicine, sports, physical therapy. Kinematics specifically studies pure motion without reference to the causes of motion such as forces. Understanding the kinematics of human movement is of critical importance in medicine and biology. Motion measure­ment can be used in order to to evaluate functional performance of limbs under normal and abnormal conditions. Kinematic knowledge is also important for diagnosis and surgi­cal treatment of joint disease and the design of implants to rehabilitate function. Accurate joint kinematics is essential to protect articular functionality. An alteration may …

Broadening The Capability Of Kinetics Analysis In Biomechanics, Nicholas Nelson

Electronic Theses and Dissertations

Two studies are discussed in this manuscript each preceded by a literature review of the topic. The first review and study explore agility movements and the effect that alternative upper designs in shoes might have on ground reaction force measures of performance. The second review and study evaluate methods of predicting ground reaction forces without the use of a force platform. A method of using effective forces and ways of improving its accuracy are evaluated in depth.

The Effects Of Increasing Running Speed On Vgrf And Asymmetry, Kaela M. Hierholzer

Electronic Theses and Dissertations

Biomechanical and physiological parameters related to running performance are usually studied separately. However, evaluating both aspects together could be beneficial in improving athletic performance. The purpose of this study was to observe the change in peak vGRF and asymmetry as speed increases, while observing physiological responses during a O_2maxtest. Data from athlete monitoring of 12 cross-country and triathlon athletes were analyzed. The athlete monitoring protocol included three unweighted countermovement jumps and a O_2maxtest performed by the athletes. The athletes had an average O_2maxof 53.4 ± 7.7 mL/kg/min, while their average vGRF asymmetry throughout the …

The Influence Of Strength In Load-Velocity Relationships In The Back Squat, Thaddeus Light

Electronic Theses and Dissertations

Load-velocity relationships may vary between people of different strength levels and across different loads. The purpose of this dissertation was to investigate how external loads influence the velocity characteristics of the back squat exercise, and the influence of strength on these variables. Healthy male students with a history of resistance training completed repetitions at specified intensities of their estimated one-repetition maximum (1RM) until they reached 1RM. Back squat 3D motion analysis was captured using four Vicon T010 cameras (Vicon Motion Systems Ltd.; Oxford, UK) and Vicon Nexus 1.8.5 software. Data were transported into R custom coding statistical analysis software (version …

Barbell Trajectory And Kinematics During Two International Weightlifting Championships, Aaron J. Cunanan

Electronic Theses and Dissertations

Several methods have been used in the scientific literature to study the weightlifting pull. Broadly, these methods are used to measure kinematic or kinetic variables exhibited by the lifter, the barbell, or the lifter-barbell system. However, there is an apparent disconnect between weightlifting research and coaching practice that may reduce the perceived benefits of technique analysis among coaches and present some challenges for coaches who seek to incorporate technique analysis into their coaching practice. Differences and trends in the technique of competitive weightlifting performances are apparent from the available literature. However, there are also gaps in the literature due to …

Kinetic And Kinematic Characteristics Of Accentuated Eccentric Loading, John Wagle

Electronic Theses and Dissertations

The current investigation was an examination of the kinetic and kinematic characteristics of the back squat using accentuated eccentric loading (AEL) and cluster set programming strategies. Trained male subjects (age = 26.1 ± 4.1 years, height = 183.5 ± 4.3 cm, body mass = 92.5 ± 10.5 kg, back squat to body mass ratio = 1.8 ± 0.3) volunteered to complete four different load condition sessions involving traditionally loaded straight sets (TL), traditionally loaded cluster sets (TLC), AEL cluster sets (AEC), and AEL straight sets where only the first repetition of each set used eccentric overload (AEL1). The use of …

Differences In Running Mechanics And Tibial Plateau Dimensions Between Overweight/Obese And Healthy Weight Children, Claire Sylvestre

Electronic Theses and Dissertations

INTRODUCTION: Overweight and obese (OW/OB) children display increased knee joint loading during running, which may lead to excessive frontal plane motion and moments at the knee joints. The relationship between tibial plateau dimensions and knee vertical loading may explain the loading related injuries OW/OB children experience.
PURPOSE: Compare knee mechanics during running and tibial plateau dimensions between healthy weight (HW) and OW/OB children.
METHODS: Ten HW children and ten OW/OB children aged 9-12 participated in the study. Kinematic and kinetic data were captured as participants ran across a force platform at 3.5m/s. Tibial plateau area and density were collected by …

Longitudinal Tracking Of Physiological State With Electromyographic Signals., Robert Warren Stallard

Electronic Theses and Dissertations

Electrophysiological measurements have been used in recent history to classify instantaneous physiological configurations, e.g., hand gestures. This work investigates the feasibility of working with changes in physiological configurations over time (i.e., longitudinally) using a variety of algorithms from the machine learning domain. We demonstrate a high degree of classification accuracy for a binary classification problem derived from electromyography measurements before and after a 35-day bedrest. The problem difficulty is increased with a more dynamic experiment testing for changes in astronaut sensorimotor performance by taking electromyography and force plate measurements before, during, and after a jump from a small platform. A …

Patient-Specific Quantification Of The Relationship Between The Left Atrium Pressure And The Ostial Diameter Of The Left Atrial Appendage, Sky Tianqi Gao

Electronic Theses and Dissertations

The left atrial appendage has been a historically understudied region of the heart until fairly recently with the new understanding of its role in the stroke pathway of patients with atrial fibrillation. The goal of this study is to take a look at the biomechanical behavior of the left atrium and left atrial appendage under normal physiological loading conditions using material properties taken from biaxial stretch tests. Several different options for material properties models were tested and biaxial stretch test data of cadaveric human tissue samples for the left atrium and appendage were fit to a Fung-type strain-energy function for …

Trunk Stability And Postural Stability In People With Multiple Sclerosis, Derek Tolbert

Electronic Theses and Dissertations

Multiple Sclerosis is a neurological disease which affects an estimated 2.5million people worldwide. People with Multiple Sclerosis often experience high rates of falls, which have been associated with age, disability, and increased postural sway. Additionally, people with Multiple Sclerosis often exhibit muscular weakness and poor responses to perturbations. PURPOSE: To determine if trunk stability and postural control are altered among PwMS and if trunk muscle activity is correlated with postural stability. METHODS: Ten participants with a physician's diagnosis of Multiple Sclerosis (9 female, 1 male) were included in this study. Ten healthy controls were matched for age, height, weight, and …

The Slippery Slope Between Falling And Recovering: An Examination Of Sensory And Somatic Factors Influencing Recovery After A Slip, Samuel J. Wilson

Electronic Theses and Dissertations

Background: Slips and falls account for large rates of injury and mortality in multiple populations. During an unexpected slip, sensory mechanisms are responsible for signaling the slip to the central nervous system, and a series of corrective responses is generated to arrest the slip and prevent a fall. While previous research has examined the corrective responses elicited, the answer of how these systems break down during a fall remains elusive. Purpose: To examine differences in postural control (slip detection), lower extremity corrective responses (slip recovery), and cortical control of the slip recovery response between individuals who fall and those who …

The Influence Of Self-Prescribed Knee Bracing On Walking In Healthy Adults, Lauren Luginsland

Electronic Theses and Dissertations

The knee is one of the most commonly loaded anatomical joints in the human body due to maintaining an upright posture. Increased joint loading can lead to various injuries which can either be treated surgically or non-surgically including immobilization by bracing. Numerous studies have looked at functional knee bracing post-operative surgery creating a gap within the literature analyzing non-operative functional knee braces within a healthy population. Commonly prescribed functional knee braces such as the Ossur Rebound® have been prescribed by physicians, but also available over-the-counter for self-prescription to assist with injury prevention, stabilization, and protection. Previous studies have looked at …

Predictive Modeling Of Hip Dislocation: Assessment Of Surgical And Patient Factors To Reduce The Occurrence Of Hip Instability And Adverse Clinical Outcomes, Daniel N. Huff

Electronic Theses and Dissertations

Instability and dislocation remain leading indications for revision of primary Total Hip Arthroplasty (THA). Many studies have addressed the links between implant design and propensity for dislocation, however a comprehensive review of the ability of modern THA constructs to protect against joint instability is needed.

Accordingly, the objective of this study is to provide objective data about THA risks to be considered in the treatment algorithm to protect against adverse joint loading conditions and joint instability. Adverse loading conditions were assessed in a population of activities of daily living using data from telemetric hip implant representation in an FE simulation …

Differences In Walking Mechanics Between A Traditional Walker And The Kb Balance Trainer, Silvia Zanini

Electronic Theses and Dissertations

INTRODUCTION: Millions of individuals with ambulatory difficulties rely on walking aids to maintain independence and mobility. However, users of traditional walkers typically exhibit increased forward lean of their trunk while using the assistive device. The KB Balance Trainer is a new posterior walker designed to facilitate a more erect position during gait. PURPOSE: To compare gait mechanics across three walking conditions: unassisted, using a traditional walker, and using the KB Balance Trainer. METHODS: Seven adults with experience using walkers due to ambulatory difficulties participated in the study. The study consisted of one training session and one gait analysis session. The …

A Kinematic Comparison Of Shoulder And Elbow Dynamics Influenced By The Shoe-Surface Interface In Youth And Adolescent Baseball Pitchers, Jacob Richard Gdovin

Electronic Theses and Dissertations

From 1994-2006, 1.5 million baseball injuries were treated within emergency departments across the United States while the upper extremity was the second most commonly injured body part. Although it has been determined that pitch count, pitch type and pitching mechanics are the main contributors to upper extremity pain in baseball pitchers, footwear has not been considered a potential factor. Therefore, the purpose of this study was to determine how baseball-specific footwear [turf shoes (ts) and molded cleats (mc)] affects the shoulder and elbow dynamics of youth and adolescent pitchers during an overhead pitch on various surface inclinations [flat ground (fg) …

Spine Lifting Biomechanics Between Varying Occupational Activity Levels And Recreational Physical Activity Levels, Caitlin Rose Francis

Electronic Theses and Dissertations

Background: Moderate to vigorous physical activity as the optimum movement patterns for health have continued to be the dominant focus of health and fitness research. Yet, emerging evidence of deleterious, adverse health effects of prolonged inactivity, independent of regular physical activity, presents a new element to establishing the ideal model of movement patterns for health. The musculoskeletal trunk of the body becomes unbalanced as a result of prolonged inactivity, and a biomechanical analysis can help to identify high-risk loading behavior associated with these unbalances. Moreover, poor spine biomechanics can indicate a need for adjustment to present recommendations for optimum movement …

The Effect Of Various Body Positions On Performance Of The Isometric Mid-Thigh Pull, George K. Beckham

Electronic Theses and Dissertations

The purpose of this dissertation was to evaluate the effects of changing body position on the execution of the isometric mid-thigh pull (IMTP). Furthermore, while there is evidence to suggest that there is an effect of familiarization on performance of maximal strength tests, there has been no known research evaluating the effect of learning on the IMTP. The effect of familiarization was assessed by evaluating changes in variables obtained from the IMTP. Subjects did not statistically improve over the five IMTP testing sessions, regardless of the body position used, or if subjects had previous experience with weightlifting derivatives. This may …

Biomechanics Of Slips In Alternative Footwear, Harish Chander

Electronic Theses and Dissertations

Injuries in the workplace pose a significant burden to the health of human beings as well as financial or economic losses to occupational organizations. Slips, trips and an induced loss of balance have been identified as the major causative factor for workplace injuries involving falls (Courtney et al, 2001; Redfern et al, 2001). The bureau of labor statistics reported 15% of a total of 4,693 workplace fatalities and a total of 299,090 cases of non-fatal workplace injuries that were due to slips, trips and falls (BLS, 2011). The purpose of the study was to analyze the biomechanics of human locomotion …

Net Impulse And Net Impulse Characteristics In Vertical Jumping, Satoshi Mizuguchi

Electronic Theses and Dissertations

The purpose of this dissertation was to explore the potential use of net impulse and its characteristics in vertical jumping to monitor athletes' performance status and responses/adaptations to interventions. Five variables were proposed as net impulse characteristics: net impulse height and width, rate of force development, shape factor, and net impulse proportion. The following were then examined: 1) test-retest reliability of a new approach to identify net impulse in a force-time curve and of net impulse characteristics and criterion validity of the new approach; 2) effective measures of net impulse characteristics; 3) relationships between training-induced changes in its characteristics and …

Impacts On Balance When Walking In Occupational Footwear, Harish Chander

Electronic Theses and Dissertations

Hazards and challenges present in the workplace pose a number of potential risks for injuries and illness. Nearly 3.1 million nonfatal workplace injuries and illness were reported in 2010 (BLS, 2010). The probability of falls has been related to balance decrements. Further, an important point of distinction is 45% of all falls have been attributed to inappropriate footwear (Menant et al. 2008) Previous studies have shown decrements in balance as a result of different footwear (Menant et al. 2008) and after an increased workload over a specific period of time (Yaggie & McGregor, 2002; Gribble & Hertel, 2004). Occupational footwear …