Biomechanics Commons^™

Mri-Based Estimation Of The Hip Joint Center In Infants Using Two Sphere-Fitting Methods, Victoria Melendez

Discovery Day - Daytona Beach

Accurate estimation of the hip joint center (HJC) is critical for biomechanical modeling and clinical assessment. Common methods include predictive methods (e.g., regression equations) and functional methods such as sphere-fitting. In infants, femoral head-based methods are often limited due to incomplete ossification of the anatomy and poor visualization in computed tomography (CT) images. This study evaluates an alternative approach using MRI-based sphere fitting of the ossified acetabular rim, comparing its accuracy to traditional femoral head-based methods. MRI scans of three male infants (ages 10.7- 12.7 months) were used to manually place landmarks on the ossified acetabulum and the cartilaginous boundary …

The Osteocyte-Osteoblast Network Requires Dynamic Mechanical Loading For Key Functions, Kevin Kowalski

Discovery Day - Daytona Beach

Spaceflight investigations have demonstrated that reduction in gravity-induced loading regimes is detrimental to maintenance Earth-normal bone and marrow. Mechanistically, however, there are still gaps in knowledge about how the reduction in gravity influences the different niches within the tissue. For example, cortical bone is a stable semi-solid structure that allows for only minor deformations before failure, while marrow is a viscous hydrogel-like material that can resist significant fluidic and compressive forces. We hypothesize that maintenance of different niches within the bone microenvironment are dependent on different loading regimes, and that the collective impact if gravity-induced loading needs to be considered …

Limb Differences In Hamstring-To-Quadricep Ratio Across Velocities In Collegiate Women’S Soccer Athletes, Nicole Waldo Johnson, Lauren Sanders, Kyle L. Sunderland

2025 Student Academic Showcase

Purpose: This study examined differences in the hamstring-to-quadriceps strength ratio (H:Q) between dominant and non-dominant legs in collegiate women soccer athletes. Methods: Eleven NCAA Division I female soccer players participated; one was excluded due to equipment malfunction. Following a standardized warm-up, athletes completed unilateral isokinetic knee extension and flexion on an isokinetic dynamometer at 60°/s, 180°/s, and 300°/s. For each leg and velocity, athletes performed three submaximal trials followed by five maximal effort repetitions, with 60 seconds of rest between velocities. A two-way repeated measures ANOVA was conducted to assess differences in H:Q ratios between the limbs across velocities. Results: …

Seasonal Improvements In Lower-Body Power In Collegiate Women’S Ice Hockey Athletes, Molly K. Henderson, Olivia J. Grabianowski, Quinn M. Mclaren, Kyle Sunderland

2025 Student Academic Showcase

The purpose of this study was to examine changes in lower-body power from pre- to post-season in a women’s ice hockey team using broad jump (BJ) and countermovement jump (CMJ) assessments. Fifteen NCAA Division I athletes completed BJ and CMJ tests within a month prior to the competitive season and within a month following the final game. All tests were conducted at a consistent time of day and began with a standardized warmup, followed by the CMJ testing using dual force plates and BJ on a marked flat surface. CMJ metrics included in the analysis were jump height, relative peak …

Lower Body Gait Variability As A Distinguishing Feature In Humans, Tyler M. Wiles, Seung Kyeom Kim, Nick Stergiou, Aaron D. Likens

UNO Student Research and Creative Activity Fair

Most humans have a fingerprint that is unique and persists throughout life. The same may be true for gait. Each person is unique physiologically and biomechanically, and has experienced a unique progression of life including injuries, habits, hobbies, or lifestyles that all contribute to navigating the world. Those individualized experiences, whether intended or not, are potentially on display in gait. We hypothesized that there are gait characteristics intrinsic and unique to everyone, so that everyone has a unique “gaitprint”, similar to humans possessing unique fingerprints. To test our hypothesis, we recruited thirty healthy young adults between the ages 19-35 as …

Postural Perturbations Change The Adaptive Response To Control, Brian Schlattmann

UNO Student Research and Creative Activity Fair

Dexterity involves cohesive and functional coordination that extends throughout the body. Successful task completion while standing hinges on synchronizing various anatomical components, ensuring postural stability across the 2D support surface. Canonical approaches account for postural sway only along the anatomical anteroposterior (AP) and mediolateral (ML) axes....

Functional Outcomes Of Noninvasive Sensory Feedback In Upper Limb Prostheses: A Meta-Analysis, Libby Caldwell

UNO Student Research and Creative Activity Fair

Noninvasive sensory feedback applies vibration or pressure to the residual limb and is thought to improve the functionality of upper limb prostheses. However, the efficacy of this approach has not been sufficiently investigated, particularly regarding actual amputee efficacy. The purpose of this study was to evaluate the functional benefits of noninvasive sensory feedback in upper limb prostheses through a meta-analysis. Electronic databases (MEDLINE, Web of Science, and PubMed) were searched up to October 2022 using the following search terms: (prosthesis OR prosthetic) AND (hand OR arm OR forearm OR transradial OR “upper limb” OR “upper extremity) AND (tactile OR haptic …

Walking With A Load On Wheels: Potential Effects Of Bidirectional Springs On Walking Economy, Hiva Razavi, Philippe Malcolm

UNO Student Research and Creative Activity Fair

Walking with a Load on Wheels: Potential Effects of Bidirectional Springs on Walking Economy

Have you ever noticed how your arms alternatively flex and extend when pushing a heavy shopping cart? Accelerating and decelerating heavy masses, such as a shopping cart, can require much effort. During walking, we alternatively accelerate and decelerate our Center of Mass (COM) in every gait cycle, which can require even more effort if we accelerate and decelerate a load while walking. Theoretically, this effort can be reduced by timing the acceleration and deceleration of the load's mass opposite to the individual's COM. Previous studies have …

Negative Impact Of Aging On Gait Autocorrelation: A Mixed-Effects Analysis Of Stride Interval Dynamics, Theodore Deligiannis, Tyler M. Wiles, Seung Kyeom Kim, Nikolaos Stergiou, Aaron Likens

UNO Student Research and Creative Activity Fair

NEGATIVE IMPACT OF AGING ON GAIT AUTOCORRELATION: A MIXED-EFFECTS ANALYSIS OF STRIDE INTERVAL DYNAMICS

Theodore A. Deligiannis^1*, Tyler M. Wiles¹, Seung Kyeom Kim¹, Nick Stergiou^1,2, Aaron D. Likens¹

¹Department of Biomechanics, University of Nebraska at Omaha

*Corresponding author’s email: [email protected]

Presentation preference: Podium

Traditional gait metrics, like speed, cadence, coordination, as well as non-linear measures, appear related to Timed Up and Go (TUG). Timed Up and Go is a clinical measurement related to physical, socioeconomic, and psychological parameters, as well as overall health. TUG can be used as a health …

Inter-Joint Variability And Age-Related Changes In Human Walking, Mehrnoush Haghighatnejad, Tyler Wiles, Seung Kyeom Kim, Aaron Likens, Nicholas Stergiou

UNO Student Research and Creative Activity Fair

Inter-Joint Variability and Age-Related Changes in Human Walking

Mehrnoush Haghighatnejad¹*, Tyler M. Wiles¹, Seung Kyeom Kim¹, Nick Stergiou^1,2, Aaron D. Likens¹

¹Department of Biomechanics, University of Nebraska at Omaha

²Department of Physical Education and Sport Science, Aristotle University, Thessaloniki, Greece

*Corresponding author’s email: [email protected]

Presentation Preference: Poster

Humans routinely perform a variety of activities such as walking, running, driving, and typing, all of which require coordination among different body joints. For instance, walking and running involve rhythmic movements of the arms and legs. The involvement of the upper …

Accelerometry-Based Analysis Of Postural Sway In Parkinson's Disease Patients With Levodopa-Induced Dyskinesia, Chandler Brock

UNO Student Research and Creative Activity Fair

Parkinson’s disease (PD) is a progressive neurodegenerative disorder, with patient numbers projected to double to 12 million in the next 20 years. Levodopa-induced dyskinesia (LID) is a major problem associated with the long-term use of levodopa for symptomatic treatment of PD. These involuntary movements can become disabling and may interfere with quality of life. Our prior research showed that PD w/ LID were less stable while standing (i.e., increased postural sway) and had a higher incidence of falls. The aim of this study is to determine if postural sway properties are altered by LID via decomposing the sway signal. We …

Walking Easier By Attaching A Spring-Mass To The Body: A Preliminary Simulation, Hiva Razavi, Philippe Malcolm

UNO Student Research and Creative Activity Fair

When carrying or pushing a load, more force is needed to accelerate and decelerate the additional mass, increasing Ground Reaction Force (GRF). However, this can be reduced by synchronizing the object's movement with the individual's Center of Mass (COM) using antiphase acceleration and deceleration. Past studies have shown this can decrease muscle work and metabolic costs. This study aimed to determine optimal spring parameters to minimize horizontal GRF (GRFh) when pushing a cart by connecting the human to the cart with a spring and damper system.

Three walking conditions were simulated in MATLAB: 1) Normal walking; 2) Walking with a …

Attenuated Skeletal Muscle Metabolism Explains Blunted Reactive Hyperemia After Prolonged Sitting, Cody Anderson, Elizabeth Pekas, Michael Allen, Song-Young Park

UNO Student Research and Creative Activity Fair

Introduction: Although reduced post-occlusive reactive hyperemia (PORH) after prolonged sitting (PS) has been reported as impaired microvascular function, no specific mechanism(s) have been elucidated. One potential mechanism, independent of microvascular function, is that an altered muscle metabolic rate (MMR) may change the magnitude of PORH by modifying the oxygen deficit achieved during cuff-induced arterial occlusions. We speculated that if MMR changes during PS, this may invalidate current inferences about microvascular function during PS. Objective: Therefore, the objective of this study was to examine if peripheral leg MMR changes during PS and to ascertain whether the change in the oxygen deficit …

The Effect Of Exoskeleton Footwear On Joint Angular Motion During Walking In Patients With Peripheral Artery Disease, Zahra Salamifar, Farahnaz Fallahtafti, Iraklis I. Pipinos, Jason M. Johanning, Sara Myers

UNO Student Research and Creative Activity Fair

Gait, Lower Extremity, Peripheral Artery Disease, Joint Angle, Exoskeleton Footwear, Exoskeleton, Assistive Device, Walking.

The Effects Of Demographics And Risk Factors On The Morphological Characteristics Of Human Femoropopliteal Arteries, Sayed Ahmadreza Razian, Majid Jadidi, Alexey Kamenskiy

UNO Student Research and Creative Activity Fair

Background: Disease of the lower extremity arteries (Peripheral Arterial Disease, PAD) is associated with high morbidity and mortality. During disease development, the arteries adapt by changing their diameter, wall thickness, and residual deformations, but the effects of demographics and risk factors on this process are not clear.

Methods: Superficial femoral arteries from 736 subjects (505 male, 231 female, 12 to 99 years old, average age 51±17.8 years) and the associated demographic and risk factor variables were used to construct machine learning (ML) regression models that predicted morphological characteristics (diameter, wall thickness, and longitudinal opening angle resulting from the …

Impact Forces And Patterns Of Axonal Injury Differ Between Two Models Of Tbi, Edward Lai, David M Devilbiss

Rowan-Virtua Research Day

Traumatic brain injury (TBI) affects approximately 3.8 million Americans a year and results in complex neuropathological and neurocognitive sequelae. Animal models of TBI attempt to replicate the impact forces and pathology of injury in humans. However, in these models, the forces generated at the time of impact are poorly understood. Nonetheless, a variety of shear and strain forces generated at the time of impact can produce diffuse axonal injury. Injury to axons and neurons across a variety of brain regions resulting from axonal injury underlies the cognitive and behavioral impairments observed after TBI. Three critical brain regions, the corpus callosum …

The Optimal Relationship Between Actuator Stiffness And Actuation Timing For A Passive Ankle Exoskeleton: An Opensim Simulation, Cody Anderson, Hafizur Rahman, Sara Myers

UNO Student Research and Creative Activity Fair

Introduction

The passive ankle exoskeleton developed by Collins et al. (2015) reduced the metabolic cost of walking with an actuation-timing of ~16% of stance [1]; however, other actuation timings have not been extensively investigated. Therefore, the purpose of this study was to determine the optimal relationship between actuator-stiffness and actuation-timing for a passive ankle exoskeleton by using musculoskeletal modeling.

Methods

Kinematics and ground reaction forces were recorded while a healthy-young male walked on overground force-plates, and these data were exported to a musculoskeletal modeling software (OpenSim) for simulation. A passive ankle exoskeleton model was designed and integrated with a default …

Ankle Foot Orthoses Improves Ground Reaction Forces In Patients With Peripheral Artery Disease, Zahra Salamifar, Farah Fallahtafti, Iraklis Pipinos, Jason Johanning, Hafizur Rahman, Mahdi Hassan, Sara Myers

UNO Student Research and Creative Activity Fair

Peripheral artery disease (PAD) is caused by atherosclerotic blockage of the arteries in the legs. Globally, over 236 million people suffer from PAD. Intermittent claudication is the most common PAD symptom that includes muscle pain, cramping, and/or aching induced by physical activities and relieved with rest. PAD impacts gait patterns: specifically, rapid ankle plantar flexion after heel contact, which decreases optimal energy transfer. An ankle-foot orthosis (AFO) is an assistive device that improves gait in patients with neurological conditions. AFOs could help patients with PAD to improve walking kinetics. The purpose of this study was to determine the impact of …

Design And Development Of Software With A Graphical User Interface To Display And Convert Multiple Microscopic Histology Images, Sayed Ahmadreza Razian, Majid Jadidi, Alexey Kamenskiy

UNO Student Research and Creative Activity Fair

Histological images are widely used to assess the microscopic anatomy of biological tissues. Recent advancements in image analysis allow the identification of structural features on histological sections that can help advance medical device development, brain and cancer research, drug discovery, vascular mechanobiology, and many other fields. Histological slide scanners create images in SVS and TIFF formats that were designed to archive image blocks and high-resolution textual information. Because these formats were primarily intended for storage, they are often not compatible with conventional image analysis software and require conversion before they can be used in research. We have developed a user-friendly …

Chair Rise Kinetics And Correlates Of Performance In Young And Older Males, Tyler Smith

Symposium of Student Scholars

Purpose: To compare chair rise kinetics in young (YM) and older (OM) males, and determine correlates of chair rise performance. METHODS: YM (n=15, age =20.7±2.2 yrs) and OM (n=15, age=71.6±3.9yrs) performed three trials of a single chair rise as quickly as possible on a force plate and the vertical ground reaction force (VGRF) signal was analyzed. Peak VGRF (PF), as well as peak (100 ms rolling average), early (minimum VGRF to 50% PF), late (50% PF to PF), and overall (minimum VGRF to PF) rate of force development (RFD; Δforce/Δtime) were calculated based on phases of the task. Power and …

The Effect Of Lumbar Support On Holding Shoulder Electromyography And Trunk Kinematics In Collegiate Violinists, Lauren Elizabeth Lee, Kevin Enstrom, Michael T. Soucy

Seaver College Research And Scholarly Achievement Symposium

Instrument-specific holding mechanics in violinists likely contribute to a high incidence of playing related musculoskeletal disorders (PRMDs). The inclusion of a lumbar support while playing may alleviate potential risks for PRMDs. PURPOSE: To investigate the effects of lumbar support on left holding shoulder musculature electromyography (EMG) activity and thigh, trunk, and hip kinematics. METHODS: Eleven (6 F; 5 M) collegiate musicians (19.5±1.3 years, 1.71±0.1 m, 68.1±7.7 kg, playing experience: 10.0±3.9 years, weekly playing time: 14.1±8.2 hours) gave voluntary informed consent and performed Prelude from Suite No. 1 in G Major (JS Bach, BWV 1007) with and without a lumbar support. …

Efficacy Of The Opensim Simulator As A Tool To Detect Changes In Gait: A Peripheral Artery Disease Model, Cody Anderson, Hafiz Rahman, Irakis Pipinos, Jason Johanning, Sara Myers

UNO Student Research and Creative Activity Fair

INTRODUCTION

Peripheral Artery Disease (PAD) is characterized by atherosclerotic plaques in the leg arteries. A common treatment for PAD is supervised exercise training [1]. However, gait is not fully restored following supervised exercise training (SET). Musculoskeletal simulation may provide insight into how muscle activation changes following SET contributed to persistent gait alterations.

METHODS

Kinematic and kinetic data from overground walking of patients with PAD (n=12), before and after a 6-month exercise intervention, was used as input for musculoskeletal modeling (OpenSim). The subjects in our sample were subdivided based on the location of ischemic muscle pain, as reported on the San …

A Systematic Review: Long Range Correlations In Running Gait, Mr. Taylor Wilson

UNO Student Research and Creative Activity Fair

Long range correlations (LRCs) are apparent in human walking and running gait and are indicative of a healthy system. A systematic review (SR) was completed to determine the typical LRC patterns in running. 20 articles were included in the SR. LRCs in running gait tend to be similar to the LRCs in walking gait, with fatigue contributing to a negative effect on the LRCs.

This SR could have implications on training guidelines for coaches and physical therapy methods to increase the LRCs in running gait for healthier functioning. More research is needed to determine how LRCs depend on running surface …

Development Of A Modular Activity-Specific Upper Limb Prosthesis, Rahul Raj

UNO Student Research and Creative Activity Fair

The use of activity-specific upper-limb prosthesis helps children with upper-limb loss to engage in functional and recreational activities, such as music and sports. The purpose of this study was to develop a modular activity-specific prosthesis and develop a remote-fitting procedure. We evaluated patient satisfaction after using the device for 8 weeks and evaluated anthropometric and range of motion (ROM) measurements of the residual limb after use of the prosthesis. We enrolled 7 children with unilateral trans-radial amputations between 7 and 12 years of age. The modular activity- specific prosthesis was specifically designed for playing musical instruments and sports. A survey …

How Stair Negotiation Affects Knee Joint Contact Forces In Individuals Post-Total Knee Arthroplasty, Todd Leutzinger

UNO Student Research and Creative Activity Fair

This study investigates how walking up and down stairs affects knee joint contact forces in individuals post-total knee arthroplasty compared to overground level walking and healthy controls.

Developing And Testing Of Low-Cost 3d Printed Prostheses To Restore And Improve Function Of Children With Congenital Or Traumatic Amputations, Rahul Raj, Christopher Copeland, Claudia Cortes Reyes, Kaitlin Fraser, David Salazar

UNO Student Research and Creative Activity Fair

The purpose of this investigation was to provide technical considerations and clinical evidence of the possible benefits and obstacles in the use of upper-limb 3D printed prostheses in paediatric populations. This information is crucial for clinicians interested in exploring the use of 3D printed prostheses for their patients. In the present study, children with congenital digit reductions (n=5); absent digits (one traumatic and four congenital) (n=5) and with upper-limb reductions (n=9). The perceived functionality of upper-limbs before the use of the prosthesis and after 4 months of use. In addition, gross dexterity, anthropometric measurements, active range of motion, and strength …

Determining The Optimal Tension For An Ankle-Foot Assistive Device, Cody Anderson

UNO Student Research and Creative Activity Fair

Introduction

Peripheral artery disease (PAD) is caused by atherosclerosis, a buildup of cholesterol and fatty acid deposits, which blocks blood flow to the arms, legs, and feet. Ankle assistive devices have recently been implemented in various clinical population to improve walking ability. Our group has developed an ankle assistive device to improve walking ability in patients with PAD. This study tested our newly developed assistive device with several tension assistance levels and their effect on metabolic cost.

Methodology

Ten healthy subjects were recruited for this study. A spring was attached to the posterior side of the device parallel to the …

The Effect Of Sensory Input On The Temporal Structure Of Center Of Pressure In Stroke Survivors, Samantha Chong

UNO Student Research and Creative Activity Fair

Stroke is the leading cause of disability that affects 17 million people worldwide. Patients post-stroke suffer from maintaining balance because the brain may not be able to receive or process visual, vestibular and proprioceptive sensory information: all of which contribute towards maintaining stability. Information provided by vision is important for spatial orientation, as it develops an environmental perspective. Proprioception is detected through the stretching of tendons and surrounding tissue and is able to help the brain determine spatial location. The vestibular system provides a sense of balance detecting rotations and linear accelerations through the vestibulo-ocular reflex. The vestibular system is …

The Effects Of Caffeine Ingestion On The Hemostatic Response To Simulated Firefighting Activities, Sierra Wassell

Showcase of Graduate Student Scholarship and Creative Activities

The leading cause of death among firefighters is sudden cardiac event, and it is acknowledged that most ischemic events are due to an occlusive thrombus formation. In addition, due to the demanding job requirements and shift work, firefighters are commonly known to overuse caffeine as an ergogenic aid. The purposes of this study were to examine the potential effects of caffeine on the hemostatic response to simulated firefighting activity.

The Perception Of Head Impacts Sustained By Collegiate Baseball Catchers: A Pilot Study, Caleb Johnston

Student Scholar Showcase

Repetitive subconcussive head impacts have been studied in a variety of contact sports and have been found to impair performance in football, soccer, hockey, and lacrosse athletes. To our knowledge no one has investigated the frequency of head impacts in the sport of collegiate baseball. To date, athlete perceived number of head impacts and actual head impacts recorded during participation have not been compared. A sample of 3 baseball catchers from one National Collegiate Athletic Association (NCAA) Division III baseball team were studied.Our results indicated perceived game impacts did not differ from actual game impacts (t₂=1.76, P=.23; …