Biomechanics Commons^™

Validation Of The Multi-Segment Foot Model With Bi-Planar Fluoroscopy, Aïda Valevicius

Electronic Thesis and Dissertation Repository

A multi-segment foot model (MSFM) is a useful tool for measuring foot joint kinematics although soft-tissue artefact is often present. Quantifying this error is needed to evaluate the accuracy of this model. This study validated the MSFM against bi-planar radiostereometric analysis (RSA) fluoroscopy. Heel-strike, mid-stance, and toe-off events during the stance phase were compared between motion capture and fluoroscopy. Rise/drop of the medial longitudinal arch showed a significant difference (p < 0.05) during toe-off, but no significant difference during heel-strike or mid-stance. Hindfoot supination/pronation and internal/external rotation, and forefoot supination/pronation motions showed no significant difference between the two techniques. The lack of significant difference will allow the MSFM to be used as a sufficiently accurate technique for measuring foot joint motions.

An Optimization Method For Estimating Joint Parameters Of The Hip And Knee, Ben Tesch

Theses and Dissertations

Biomechanics, generally speaking, concerns the application of engineeringprinciples to the study of living things. This work is concerned withhuman movement analysis, a subfield of biomechanics, where the methodsof classical mechanics are applied to human movement. This field hascontributed to the general understanding of human movement, and itstechniques are used in the diagnosis and treatment of disease. Centralto the field is the process of measuring human movement. Since classicalmechanics deals with the motion of rigid bodies, and ideal measurementsystem would be able to accurately record the exact pose --- combinedposition and orientation --- of the bones. The techniques that reachthis ideal …

Investigating The Effects Of Biochemical And Biophysical Signals On Vascular Smooth Muscle Cell Differentiation, Ruikai Chen

All Dissertations

In blood vessel engineering, an optimal bioartifical scaffold can be characterized as a 3D tubular structure with high porosity for nutrient diffusion and enough mechanical strength to sustain in vivo dynamic environment. The luminal surface of the scaffold is supposed to have a continuous layer of endothelial cell that is ideally non-immunogenic and non-thrombogenic while the media layer of the construct is assigned for the ingrowth of vascular smooth muscle cell which can provide structural integrity and contractility. While reconstructing endothelial cell layer has been at the center of interest in most polymeric vascular replacements related research, growing VSMCs has …

Role Of Sensation In Altered Phalanx Grip Force In Persons With Stroke, Leah R. Enders

Theses and Dissertations

Many individuals experience hand impairment after stroke leading to decreased ability to perform daily living activities. Previous research studies have investigated how stroke survivors' pinch grip control differs from healthy individuals, even though many individuals can only grasp with power grip after stroke. Furthermore, many stroke survivors experience tactile sensory deficit in their paretic limb in addition to motor deficit. It is currently unknown how stroke induced tactile sensory deficit affects power grip force directional control, which is important in terms of preventing object slippage and power grip normal force generation. Additionally it is unknown if power grip could be …

Practical Applications Of Biomechanical Principles In Resistance Training: Neuromuscular Factors And Relationships, Jason Lake, Paul A. Swinton, Justin Keogh

Justin Keogh

This paper is the second in our three part series examining how a variety of biomechanical principles and concepts have direct relevance to the prescription of resistance training for the general and athletic populations as well as for musculoskeletal injury rehabilitation. In this paper, we considered different neuromuscular characteristics of resistance exercise. We started by defining the causes of motion, discussing force and Newton’s second law of linear motion. This led to discussion of impulse, and how its relationship with momentum can be used to study force-time curves recorded from different ground-based resistance exercises. This enables the sports biomechanist to …

University Of Nebraska At Omaha Biomechanics Research Building Annual Report, Fall 2014, Biomechanics Research Building

Biomechanics Annual Report

This annual report features:

Letter from the Directer; COBRE Grant Press Release

Updates - Our New Building; Visitors; Moving on Up; Why Choose BRB as a Student?; Where Are They Now?; From the Bench to the Market

Projects - Neuroscience; NASA: Stimulation of the Sensory System; Motor Development; Variability Studies; Path Integration; Peripheral Artery Disease and Aging

Other Content - Beyond our Borders; Journal Club; Awards; Faculty Travels; Conferences; NE Science Fest; Campaign for Nebraska

Effects Of Yoga On Arm Volume Among Women With Breast Cancer Related Lymphedema: A Pilot Study, Mary Insana Fisher, Betsy Donahoe-Fillmore, Laura Leach, Colleen O'Malley, Cheryl Paeplow, Tess Prescott, Harold L. Merriman

Physical Therapy Faculty Publications

Lymphedema affects 3–58% of survivors of breast cancer and can result in upper extremity impairments. Exercise can be beneficial in managing lymphedema. Yoga practice has been minimally studied for its effects on breast cancer related lymphedema (BCRL). The purpose of this study was to determine the effect of yoga on arm volume, quality of life (QOL), self-reported arm function, and hand grip strength in women with BCRL. Six women with BCRL participated in modified Hatha yoga 3×/week for 8 weeks. Compression sleeves were worn during yoga sessions. Arm volume, QOL, self-reported arm function, and hand grip strength were measured at …

Locomotor Sensory Organization Test: A Novel Paradigm For The Assessment Of Sensory Contributions In Gait, Jung Hung Chien, Diderik-Jan Eikema, Mukul Mukherjee, Nicholas Stergiou

Journal Articles

Feedback based balance control requires the integration of visual, proprioceptive and vestibular input to detect the body’s movement within the environment. When the accuracy of sensory signals is compromised, the system reorganizes the relative contributions through a process of sensory recalibration, for upright postural stability to be maintained. Whereas this process has been studied extensively in standing using the Sensory Organization Test (SOT), less is known about these processes in more dynamic tasks such as locomotion. In the present study, ten healthy young adults performed the six conditions of the traditional SOT to quantify standing postural control when exposed to …

Motor Output Structure In Targeted Aiming: A Mechanistic Model, Dale Lewis, Roger Young, Jeffrey Eder, Andrew B, Slifkin

Undergraduate Research Posters 2014

Studies using a variety of experimental tasks have established that when humans repeatedly produce an action, fluctuations in action output are highest at the lowest frequencies and fluctuation magnitude (power) systematically declines as frequency increases. Such time series structure is termed pink noise. However, the appearance of pink noise seems to be limited to tasks where action is executed in the absence of task-related feedback. A few studies have demonstrated that when action was executed in the presence of task-related feedback, power was evenly distributed across all spectral frequencies—i.e., white noise was revealed. Here, participants produced cyclical aiming movements under …

Locomotor Sensory Organization Test: A Novel Paradigm For The Assessment Of Sensory Contributions In Gait, Jung Hung Chien, Diderik Jan Anthony Eikema, Mukul Mukherjee, Nikolaos Stergiou

Journal Articles

Feedback based balance control requires the integration of visual, proprioceptive and vestibular input to detect the body’s movement within the environment. When the accuracy of sensory signals is compromised, the system reorganizes the relative contributions through a process of sensory recalibration, for upright postural stability to be maintained. Whereas this process has been studied extensively in standing using the Sensory Organization Test (SOT), less is known about these processes in more dynamic tasks such as locomotion. In the present study, ten healthy young adults performed the six conditions of the traditional SOT to quantify standing postural control when exposed to …

How Sensitive Is The Deltoid Moment Arm To Joint Center Changes With Rtsa?, David Walker, Allison Kinney, Aimee Struk, Benjamin J. Fregly, Thomas Wright, Scott Banks

Mechanical and Aerospace Engineering Faculty Publications

The goal of this study was to assess the sensitivity of the deltoid muscle moment arms as a function of joint configuration for an existing RTSA subject. High variations were found for all three deltoid components. Variation over the entire abduction arc was greatest in the anterior and lateral deltoid, while the posterior deltoid moment arm was mostly sensitive to joint center changes early in the abduction arc. Moment arm changes of 10-16mm represent a significant amount of the total deltoid moment arm. This means there is an opportunity to dramatically change the deltoid moments arms through surgical placement of …

Deltoid Moment Arms During Abduction: A Subject-Specific Musculoskeletal Modeling Study In Healthy Shoulders And Shoulders With Rtsa, David Walker, Allison Kinney, Aimee Struk, Benjamin J. Fregly, Thomas Wright, Scott Banks

Mechanical and Aerospace Engineering Faculty Publications

Reverse total shoulder arthroplasty (RTSA) is increasingly used in the United States since approval by the FDA in 2003. RTSA relieves pain and restores mobility in arthritic rotator cuff deficient shoulders. Though many advantages of RTSA have been demonstrated, there still are a variety of complications (implant loosening, shoulder impingement, infection, frozen shoulder) making apparent much still is to be learned how RTSA modifies normal shoulder function. The goal of this study was to assess how RTSA affects deltoid muscle moment generating capacity post-surgery using a subjectspecific computational model driven by in vivo kinematic data.

A Novel Approach To Estimation Of Patient-Specific Muscle Strength, David Walker, Allison Kinney, Benjamin J. Fregly, Thomas Wright, Scott Banks

Mechanical and Aerospace Engineering Faculty Publications

Current modeling techniques have been used to model the Reverse Total Shoulder Arthroplasty (RTSA) to account for the geometric changes implemented after RTSA. Though these models have provided insight into the effects of geometric changes from RTSA these is still a limitation of understanding muscle function after RTSA on a patient-specific basis. The goal of this study sought to overcome this limitation by developing an approach to calibrate patient-specific muscle strength for an RTSA subject.

Gaze And Posture Coordinate Differently With The Complexity Of Visual Stimulus Motion, Joshua L. Haworth, Srikant Vallabhajosula, Nikolaos Stergiou

Journal Articles

In this study, we explored whether gaze and posture would exhibit coordination with the motion of a presented visual stimulus, specifically with regard to the complexity of the motion structure. Fourteen healthy adults viewed a set of four visual stimulus motion conditions, in both self-selected and semi-tandem stance, during which the stimulus moved horizontally across a screen, with position updated to follow a sine, chaos, surrogate, or random noise trajectory. Posture was measured using a standard force platform in self-selected and semi-tandem stance conditions while gaze was recorded using image-based eye-tracking equipment. Cross-correlation confirmed the continuous coordination of gaze with …

Lower Extremity Injury In Female Basketball Players Is Related To A Large Difference In Peak Eversion Torque Between Barefoot And Shod Conditions, Jenna M. Yentes, Max J. Kurz, Nikolaos Stergiou

Journal Articles

Background
The majority of injuries reported in female basketball players are ankle sprains and mechanisms leading to injury have been debated. Investigations into muscular imbalances in barefoot versus shod conditions and their relationship with injury severity have not been performed. The purpose of this study was to investigate the effects of wearing athletic shoes on muscular strength and its relationship to lower extremity injuries, specifically female basketball players due to the high incidence of ankle injuries in this population.

Methods
During pre-season, 11 female collegiate basketball players underwent inversion and eversion muscle strength testing using an isokinetic dynamometer in both …

Kinetic Asymmetries During Submaximal And Maximal Speed Running, Devon H. Frayne

Masters Theses

An important issue for sports scientists, coaches and athletes is an understanding of the factors within a running stride that can enhance or limit maximal running speed. Previous research has identified many sprint-related parameters as potential kinetic limiters of maximal Center of Mass velocity (Chapman and Caldwell, 1983b; Weyand et al., 2001). Bilateral asymmetry is present for many of these parameters during running; however the degree to which such asymmetries change as running speed increases is unknown. It was hypothesized that asymmetries in key sprinting parameters would be larger at maximal speed than all other tested speeds. Kinematics and kinetics …

Evaluating The Similarity In Postures Between Forklift Operators In Virtual Reality And The Workplace, Youngmin Jun

Electronic Thesis and Dissertation Repository

Forklift operators must adopt awkward postures in order to gain appropriate lines of sight; these postures are associated with musculoskeletal injuries and disorders such as low back pain and neck pain. The purpose of this thesis was to evaluate the similarity in postures between forklift operators in virtual reality simulation of forklift loading and unloading operations and a corresponding real world workplace. This evaluation will help determine whether the virtual reality system is a useful tool for performing controlled laboratory-based investigations of ergonomics issues in heavy mobile machinery. One certified forklift operator and one uncertified individual performed two cycles of …

The Effects Of Oar-Shaft Stiffness And Length On Rowing Biomechanics, Brock Laschowski

Electronic Thesis and Dissertation Repository

This work investigates the effects of oar-shaft stiffness and length on rowing biomechanics. The mechanical properties of the oar-shafts were examined using an end-loaded cantilever system, and theoretical relations were proposed between the mechanics of the oar-shafts and rowing performance. On-water experiments were subsequently conducted and rowing biomechanics measured via the PowerLine Rowing Instrumentation System. The PowerLine system measures force and oar angle on the oarlock, as well as proper boat acceleration. The convergent validity and test-retest reliability of the PowerLine force measurements were determined prior to the on-water experiments. Thereafter, rowers were tested over a set distance using oar-shafts …

Comprehensive Analysis Of Abdominal Tendon Length:Muscle Length Ratios In Human And Rat Specimens, Alexander J. Stephen

Electronic Thesis and Dissertation Repository

Introduction: This study measured and described the tendon to muscle length ratios (TMRs) of the external oblique (EO), internal oblique (IO), rectus abdominus (RA), and transverse abdominus (TrA) muscles in humans and rats. Methods: The abdominal muscles of human and rat specimens were dissected and the length of the muscle fibers from their posterior attachments to the lumbodorsal fascia or the rib cage, and the lengths of their tendons, were measured. The tendon length was divided by muscle fiber length to calculate the TMR. Results: The TMRs for the human EO, IO, and TrA muscles were significantly larger than the …

Stride Length-Speed Relationship During Body Weight Supported Running, Carmen Chona

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to determine if body weight support influences the stride length-speed relationship. Additionally, the purpose was to determine if impact characteristics of running are influenced by body weight support and speed. Subjects (n=10; 6 female, 4 male) volunteered to participate in this study. All subjects were injury free and were comfortable running on a treadmill for 30 minutes. Subjects ran on a lower body positive (LBPP, Alter-G, G-Trainer) treadmill for 4 conditions of body weight (100, 40, 30 and 20% of body weight) and 4 running speeds (100, 110, 120 and 130% of the preferred …

The Effect Of Attentional Focus Instructions On Golf Swing Performance In Recreational Golfers, Jeffrey D. Eggleston

Boise State University Theses and Dissertations

Previous research has addressed the effectiveness of attentional focus instructions in improving golf performance with a single training session. The purpose of the current study was to investigate the effect of external (EF) attentional focus instructions on recreational golfers’ performance over a distributed training period and extended retention interval. Performance was measured by club head velocity (CHV) and X-factor as both have been correlated with greater performance. The current study extends the work of An, Wulf, and Kim (2013), by increasing the training period and retention interval. It was hypothesized EF group would have greater CHV and X-factor measurements during …

Biomechanical Evaluation Of A Jackhammering Task With And Without List Assist, Blake Allen Johnson

Theses and Dissertations

The construction and utility industries have relatively high levels of hazardous tasks that impose high physical demands on a worker. For the past decade these industry sectors had one of highest incident rates for non-fatal injuries (BLS, 2013). The task of operating a jackhammer presents several risk factors that promote the high rates of injuries to this industry sector. Until the introduction of the lift assist, relatively few interventions were available to make the task of operating a jackhammer safer. However, no research has been conducted to support that this device is able to make jackhammering safer. The aim of …

The Influence Of Auditory-Motor Coupling On Fractal Dynamics In Human Gait, Nathaniel Hunt, Denise Mcgrath, Nikolaos Stergiou

Journal Articles

Humans exhibit an innate ability to synchronize their movements to music. The field of gait rehabilitation has sought to capitalize on this phenomenon by invoking patients to walk in time to rhythmic auditory cues with a view to improving pathological gait. However, the temporal structure of the auditory cue, and hence the temporal structure of the target behavior has not been sufficiently explored. This study reveals the plasticity of auditory-motor coupling in human walking in relation to ‘complex’ auditory cues. The authors demonstrate that auditory-motor coupling can be driven by different coloured auditory noise signals (e.g. white, brown), shifting the …

Evaluation Of The Functional Capabilities Of Fins And Limbs For Moving On Land: Insights Into The Invasion Of Land By Tetrapods, Sandy Kawano

All Dissertations

Transitions to novel habitats present different adaptive challenges, producing captivating examples of how functional innovations of the musculoskeletal system influence phenotypic divergence and adaptive radiations. One intriguing example is the transition from aquatic fishes to tetrapods. Recent technological advances and discoveries of critical fossils have catapulted our understanding on how fishes gave rise to terrestrial vertebrates. Considerable attention has been paid to legged locomotion on land, but given that the first tetrapods were aquatic, limbs did not evolve primarily for terrestriality. How, then, is the locomotor function of limbs different from fins? Extant amphibious fishes demonstrate that fins can be …

Effects Of Different Approach Directions And Sizes Of Selected Tennis Forehand Strokes On Knee Biomechanics, Louise Barbara Beggs

Masters Theses

Tennis is a global sport and knee injuries are prevalent, ranging from acute to chronic and minor, to severe. Different directional movements and speeds involved in tennis may lead to a higher chance of injury due to changing loading rates at the knee. This study investigates effects of diagonal and lateral forehand strokes with step or lunge on kinematics and kinetics of the knee on the dominant leg during simulated tennis play. Ten National Tennis Ranking Program (NTRP) players level 4.0 upwards were recruited for the study. A motion analysis system was used to obtain three-dimensional joint kinematics, and force …

Knee Biomechanical Characteristics Of Knee Unfriendly Movements In 42-Form Tai Ji, Chen Wen

Masters Theses

Tai Ji was one of recommended non-pharmacologic treatments for knee OA, but it is not clear that if all of the Tai Ji movements would be suitable and beneficial for knee OA patients. The purpose of this study was to examine 1) GRF and knee kinematic and kinetic characteristics of the identified knee unfriendly Tai Ji movements including lunges, pushdown, kick and pseudo-step 2) effects of high- and low-pose of these movements on those characteristics, and 3) compare biomechanical variables between the Tai Ji movements and slow waking. Seventeen volunteers performed three trials in each of eight movement conditions: high …

A Comparative Evaluation Of The Effects Of Incline On Kinematics And Muscle Function During Backward Walking, Daniel Brent Jensen

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to investigate lower extremity kinematics and muscle activation patterns in inclined backward walking (IBW) versus traditional backward walking (BW). This purpose was achieved by evaluating performance of individuals walking backward on a treadmill at inclines of 0%, 6%, 8%, 10%, and 12%. Eleven participants (24.9 ± 4.8 yrs, 71.9 ± 11.6 kg, 1.7 ± 0.09m) recruited from the UNLV student body went through a familiarization training program before any data were collected. The familiarization training, which took place across 3 different days, served to: 1) help the participants become comfortable and familiar with BW …

An Evaluation Of Kinematic Variables During Stance Phase Of A Training Endurance Run, Joshua Paul Bailey

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of the study was to evaluate kinematics of the lower extremity during the stance phase of an endurance training run. Fifteen participants (8 male, 7 female; 30.5 ± 8.4 years; 71.8 ± 11 kg; 1.73 ± 0.07 m) reported that they were currently signed up for, or planned on signing up for, an endurance race within the next six months of participation in the study (9 half marathon, 3 marathon, 1 triathlon, 2 21k trail run). All had a weekly running mileage greater than 20 miles (23.8 ±4.6 miles). Participants were required to complete the 15–kilometer training run …

The Effects Of Opedix < Sup > Tm < / Sup > Knee Support System, Philip Mathew

Theses and Dissertations

INTRODUCTION: Knee supports are often employed to decrease adductor angle and/or adductor moment and thus medial knee joint loading in persons with medial knee osteoarthritis. It is compelling that these gait alterations would also be considered beneficial in healthy individuals from a prophylactic application. While the Opedix product was designed specifically as a knee support system, in the present study lower extremity kinematic chain with emphasis on hip and knee were investigated.

PURPOSE: The purpose of this study was to test Opedix garments and describe the changes in sagittal (X), frontal (Y), and transverse (Z) planes for both kinematic and …

Analysis And Application Of Passive Gait Rehabilitation Methods, Ismet Handzic

USF Tampa Graduate Theses and Dissertations

Human gait is elegant and efficient in propelling the body forward. While a healthy human gait is symmetric, any deviation from symmetry can cause inefficiencies to the entire body. Such asymmetries may present themselves in hemiplegic patients, prosthetic users, lower limb injuries, limb height and weight discrepancies, or abnormal overground foot rolling. In this dissertation, practical passive methods to alleviate such asymmetric walking dynamics are presented. The novel concepts presented in this manuscript can all be related and applied to passive gait rehabilitation, that is, the rehabilitation of a person's gait through methods that do not require external power. One …