Biomechanics Commons^™

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.

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 …

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 …

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 …

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 …

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 …

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 …

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 …

Lateral Line Analogue Aids Vision In Successful Predator Evasion For The Brief Squid, Lolliguncula Brevis, Carly A. York, Ian K. Bartol

Biological Sciences Faculty Publications

Cephalopods have visual and mechanoreception systems that may be employed to sense and respond to an approaching predator. While vision presumably plays the dominant role, the importance of the lateral line analogue for predator evasion has not been examined in cephalopods. To test the respective roles of vision and the lateral line analogue, brief squid, Lolliguncula brevis, were observed in the presence of summer flounder, Paralichthys dentatus, under light and dark conditions with their lateral line analogue intact and ablated. Hair cell ablation was achieved through a pharmacological technique used for the first time on a cephalopod. The …

Adaptation And Prosthesis Effects On Stride-To-Stride Fluctuations In Amputee Gait, Shane R. Wurdeman, Sara A. Myers, Adam L. Jacobsen, Nikolaos Stergiou

Journal Articles

Twenty-four individuals with transtibial amputation were recruited to a randomized, crossover design study to examine stride-to-stride fluctuations of lower limb joint flexion/extension time series using the largest Lyapunov exponent (λ). Each individual wore a “more appropriate” and a “less appropriate” prosthesis design based on the subject's previous functional classification for a three week adaptation period. Results showed decreased λ for the sound ankle compared to the prosthetic ankle (F_1,23 = 13.897, p = 0.001) and a decreased λ for the “more appropriate” prosthesis (F_1,23 = 4.849, p = 0.038). There was also a significant effect for the time …

Do Right-Handed Monkeys Use The Right Cheek Pouch Before The Left?, Madhur Mangalam, Nisarg Desai, Mewa Singh

Journal Articles

There can be several factors that are likely to have played a role in the evolution of hand preference in humans and non-human primates, which the existing theories do not consider. There exists a possibility that hand preference in non-human primates evolved from the pre-existing lateralities in more elementary brain functions and behavior, or alternatively, the two coevolved. A basic example can be a hand-mouth command system that could have evolved in the context of ingestion. In the present study, we examined the relationship between lateralities in prehension and mastication processes, that is, hand and cheek pouch usage, in free-ranging …

Twenty-Four Hour Post-Exercise Hypotension Following Concurrent Cardiovascular And Resistance Exercise, Whitley J. Stone

Masters Theses & Specialist Projects

Despite pharmacological advances, exercise remains a cost effective preventative for cardiovascular disease (CVD) by acutely and chronically lowering systolic blood pressure (SBP). Although numerous studies have investigated aerobic and resistance training’s role in eliciting an acute SBP response termed post-exercise hypotension (PEH), few researchers have investigated how performing both cardiovascular and weight training in a single session (concurrent training) or how different prescriptions for order of exercise modality will elicit this PEH response; no known studies have attempted altering the order of exercise types within each session. This study seeks to determine if the order of exercise type will affect …

Sitting And Looking: The Development Of Stability And Visual Exploration, Regina T. Harbourne, Bridget O. Ryalls, Nikolaos Stergiou

Journal Articles

This longitudinal study focused on the interaction of developing sitting postural control with look time, which served as a measure for cognitive processing. Twenty-eight typically developing infants and 16 infants with motor delays were evaluated using center-of-pressure measures to assess stability of sitting postural control and videography to assess look time at objects, at three progressive stages of sitting development. Results indicated that look time decreased significantly in conjunction with a significant increase in postural stability in both groups as sitting progressed to independence. Infants with motor delays showed significantly longer looks when compared to typical infants at the middle …

The Effects Of Apoe Knock Out On Skeletal Muscle Regeneration: A Look Into Markers Of Protein Synthesis And Satellite Cell Function, Joshua Eden Ragland

Graduate Theses and Dissertations

ApoE helps regulate serum cholesterol levels by adding in transport of cholesterol into the cells, as well as, to the liver. ApoE knockout mice (ApoE KO) present a model that demonstrates the effects of hypercholesterolemia. Damage to muscle stimulates a complex regenerative response. The effects of high cholesterol on this regenerative response are not known. PURPOSE: To determine if skeletal muscle regeneration is altered in apoE KO mice by measuring protein synthesis regulator IGF-1, Akt, mTOR, and p70S6K, cell cycle regulator cyclin D1, and myogenic regulatory factors myoD and myogenin. METHODS: Female C57/BL6 (WT) and apoE KO were assigned to …

Biomechanical Analysis Of Gait Kinetics Resulting From Use Of A Vacuum Socket On A Transtibial Prosthesis, Maria De Lourdes Ramos Gonzalez

Honors College Theses

The technology and design of lower limb prosthetics have evolved greatly since their introduction. The current study proposed to compare the effects of a conventional pin socket attachment and a vacuum socket attachment for a transtibial amputee. Whereas traditional measurements of gait utilize force plates and camera systems, this study made use of a small tri-axial load cell located at the base of the socket to measure the forces and moments exerted during a regular gait cycle. The hypothesis tested stated that a vacuum pump socket attachment, when compared to a non-vacuum (pin) socket, will have a significant effect on …

Effects Of An In-Season Resistance Training Program On Lower Extremity Power Output In Collegiate Basketball Players, Kevin Lee King

Graduate Theses and Dissertations

The purpose of this study was to evaluate changes in muscle power performance in a horizontal (forward movement), vertical, and lateral directions in collegiate basketball players due to the presence of an in-season resistance training program (ISRTP). Four basketball teams were recruited for this study. Two women's basketball teams and two men's basketball teams participated with one team in each gender participating in an ISRTP and one team not participating in an ISRTP. Fifty-three collegiate basketball players (Females= 29, Males= 24) were successfully recruited for this project. Subjects were assessed for lower extremity muscle power and muscle strength at pre-season, …

Asymmetric Unilateral Transfemoral Prosthetic Simulator, Tyagi Ramakrishnan

USF Tampa Graduate Theses and Dissertations

amputation, which includes reduced force generation at the knee and ankle, reduced control of the leg, and different mass properties relative to their intact leg. The physical change in the prosthetic leg leads to gait asymmetries that include spatial, temporal, or force differences. This altered gait can lead to an increase in energy consumption and pain due to compensating forces and torques. The asymmetric prosthesis demonstrated in this research aims to find a balance between the different types of asymmetries to provide a gait that is more symmetric and to make it overall easier for an amputee to walk.

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The Effects Of A Foot-Toe Orthosis On Dynamic Balance And Hallux Valgus Angle, Adam Richard Kelly

Theses and Dissertations

Context: Decreased balance has been identified as a risk factor for lower extremity injury in several populations. Previous literature has investigated the effects of using orthotics, textured insoles and textured surfaces on balance. However, no research exists on the effects of a foot-toe orthosis on dynamic balance. Objective: To determine the effects of a foot-toe orthosis on dynamic balance and hallux valgus angle. Design: A randomized controlled trial. Setting: Athletic Training research laboratory. Participants: Sixty-three healthy and recreationally active collegiate students. (age: 21.59±1.49yrs, height 172.48±8.99cm, mass 73.86kg±15.64kg) Interventions: Participants were randomly allocated to one of three groups that received either …