Biomedical Engineering and Bioengineering Commons^™

Predicting The Progression Of Diabetes Mellitus Using Dynamic Plantar Pressure Parameters, Mathew Sunil Varre

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: Diabetic peripheral neuropathy is one of the common complications of type-2 diabetes mellitus (DM). Changes in the intrinsic plantar tissue coupled with repetitive mechanical loads and loss of sensation may lead to foot related complications (skin break down, ulcerations, and amputations) in persons with neuropathy if left untreated. The purpose of this dissertation was to stratify individuals with pre-diabetes, diabetes with and without neuropathy using dynamic plantar pressure parameters during walking, using machine learning algorithms.Methods: Plantar pressure data was collected from one hundred participants during walking with pressure measuring insoles fixed between the feet and thin socks. Simultaneously high-definition …

Utilizing Neural Networks And Wearables To Quantify Hip Joint Angles And Moments During Walking And Stair Ascent, Megan V. Mccabe

ENGS 88 Honors Thesis (AB Students)

Wearable sensors were leveraged to develop two methods for computing hip joint angles and moments during walking and stair ascent that are more portable than the gold standard. The Insole-Standard (I-S) approach replaced force plates with force-measuring insoles and achieved results that match the curvature of results from similar studies. Peaks in I-S kinetic results are high due to error induced by applying the ground reaction force to the talus. The Wearable-ANN (W-A) approach combines wearables with artificial neural networks to compute the same results. Compared against the I-S, the W-A approach performs well (average rRMSE = 18%, R^{2 …}

Walking Kinematics In Young Children With Limb Loss Using Early Versus Traditional Prosthetic Knee Prescription Protocols, Mark Daniel Geil, Zahra Safaeepour, Brian Giavedoni, Colleen Coulter

Faculty and Research Publications

The traditional treatment protocol for young children with congenital or acquired amputations at or proximal to the knee prescribes a prosthesis without a working knee joint, based in part on the assumption that a child learning to walk cannot properly utilize a passively flexing prosthetic knee component. An alternative to this Traditional Knee (TK) protocol is an “Early Knee” (EK) protocol, which prescribes an articulating prosthetic knee in the child’s first prosthesis, during development of crawling and transitioning into and out of upright positions. To date, no study has compared samples of children with limb loss at or proximal to …

Predictive Simulation Of Human Movement And Applications To Assistive Device Design And Control, Vinh Nguyen

Doctoral Dissertations

Predictive simulation based on dynamic optimization using musculoskeletal models is a powerful approach for studying biomechanics of human gait. Predictive simulation can be used for a variety of applications from designing assistive devices to testing theories of motor controls. However, one of the challenges in formulating the predictive dynamic optimization problem is that the cost function, which represents the underlying goal of the walking task (e.g., minimal energy consumption) is generally unknown and is assumed a priori. While different studies used different cost functions, the qualities of the gaits with those cost functions were often not provided. Therefore, this dissertation …

Ideomotion Gait Training Thigh Prompt, Kristin Schmidt, Elizabeth Peterson, Dalton Jennings

Biomedical Engineering

This document serves as our project report at its completion for developing thigh prompts to be used with the LiftWalker. In this document we outline our project from its beginning to end. We describe our process from understanding the background and our customer requirements, transforming these customer requirements into engineering specifications, performing the stage gate process, developing and evolving the design, testing the design, and finally drawing conclusions and making recommendations for the future.

Walking Biomechanics And Energetics Of Individuals With A Visual Impairment: A Preliminary Report, Hunter J. Bennett, Kevin A. Valenzuela, Kristina Fleenor, Steven Morrison, Justin A. Haegele

Human Movement Sciences Faculty Publications

Purpose.

Although walking gait in sighted populations is well researched, few studies have investigated persons with visual impairments (VIs). Given the lack of physical activity in people with VIs, it is possible that reduced efficiency in walking could adversely affect activity. The purposes of this preliminary study were to (1) examine the biomechanics and energetics utilized during independent and guided walking in subjects with VIs, and (2) compare gait biomechanics between people with VIs and sighted controls.

Methods.

Three-dimensional motion capture and force platforms were used during independent and guided walking at self-selected speeds. Joint angles, moments, external work, and …

Gait Rehabilitation Using Functional Electrical Stimulation Induces Changes In Ankle Muscle Coordination In Stroke Survivors: A Preliminary Study, Jessica L. Allen, Lena H. Ting, Trisha M. Kesar

Faculty & Staff Scholarship

No abstract provided.

Assessing The Validity Of Pressure-Measuring Insoles In Quantifying Gait Variables, Jessica Deberardinis, Janet S. Dufek, Mohamed B. Trabia, Daniel E. Lidstone

Integrated Health Sciences Faculty Publications

Introduction Pressure-measuring insoles can provide a portable alternative to existing gait analysis tools. However, there is disagreement among researchers on their accuracy and the appropriate calibration methods. The purposes of this study were to (1) determine the validity of pressure-measuring insoles for calculating stance time and support-phase impulse during walking using two calibration procedures, and (2) examine the effect of insole size on the results. Methods Data were collected from 39 participants (23.5 ± 3.24 yrs, 66.7 ± 17.5 kg, 1.64 ± 0.09 m), each wearing appropriately sized insoles as they walked over two consecutive force platforms. Two calibration methods …

Cortical Oscillations During A Lateral Balance Perturbation While Walking, Joseph Lee

Dissertations (1934 -)

The role of sensory systems in the cortical control of dynamic balance was examined using electroencephalography (EEG) recordings during balance perturbations while walking. Specifically, we examined the impact of sensory deficits on cortical oscillations using vibratory stimuli to suppress sensory feedback and by comparing cortical oscillations during balance perturbations while walking in people with sensory deficits associated with cervical myelopathy and neurologically intact controls. Balance during walking provides a rich framework for investigating cortical control using EEG during a functionally relevant task. While this approach is promising, substantial technical challenges remain in recording and processing EEG in the noisy, artifact …

Functional Comparison Of Conventional Afos With The Dynamic Response Afo, Mitchell Ruble

Master's Theses (2009 -)

Ankle foot orthoses (AFOs) are commonly prescribed to provide stability and foot clearance for patients with weakened or injured musculature. The Dynamic Response AFO (DRAFO) was designed to improve proprioception at heel strike. The design includes a rigid outer shell with a cut out heel and a soft inner lining; it is typically aligned in plantarflexion and may incorporate external heel wedges. The objective of this study was to investigate the effects of the DRAFO design features and contrast its biomechanical function with that of conventional locked and articulating AFOs. The research hypotheses were: 1) DRAFO-assisted gait parameters (e.g. ankle …

Stroke-Related Effects On Maximal Dynamic Hip Flexor Fatigability And Functional Implications, Henry Kuhnen, Megan M. Rybar, Tanya Onushko, Ryan E. Doyel, Sandra K. Hunter, Brian D. Schmit, Allison Hyngstrom

Exercise Science Faculty Research and Publications

Introduction: Stroke-related changes in maximal dynamic hip flexor muscle fatigability may be more relevant functionally than isometric hip flexor fatigability. Methods: Ten chronic stroke survivors performed 5 sets of 30 hip flexion maximal dynamic voluntary contractions (MDVC). A maximal isometric voluntary contraction (MIVC) was performed before and after completion of the dynamic contractions. Both the paretic and nonparetic legs were tested. Results: Reduction in hip flexion MDVC torque in the paretic leg (44.7%) was larger than the nonparetic leg (31.7%). The paretic leg had a larger reduction in rectus femoris EMG (28.9%) between the first and last …

Robotic Resistance/Assistance Training Improves Locomotor Function In Individuals Poststroke: A Randomized Controlled Study, Ming Wu, Jill M. Landry, Janis Kim, Brian D. Schmit, Sheng-Che Yen, Jillian Macdonald

Biomedical Engineering Faculty Research and Publications

Objective

To determine whether providing a controlled resistance versus assistance to the paretic leg at the ankle during treadmill training will improve walking function in individuals poststroke.

Design

Repeated assessment of the same patients with parallel design and randomized controlled study between 2 groups.

Setting

Research units of rehabilitation hospitals.

Participants

Patients (N=30) with chronic stroke.

Intervention

Subjects were stratified based on self-selected walking speed and were randomly assigned to the resistance or assistance training group. For the resistance group, a controlled resistance load was applied to the paretic leg at the ankle to resist leg swing during treadmill walking. …

Dynamic Balance Control During Treadmill Walking In Chronic Stroke Survivors, Eric Richard Walker

Dissertations (1934 -)

Maintaining dynamic balance is an important component of walking function that is likely impaired in chronic stroke survivors, evidenced by an increased prevalence of falls. Dynamic balance control requires maintaining the center of mass (COM) within the base of support during movement. During walking, dynamic balance control is achieved largely by modifying foot placement to adjust the base of support. However, chronic stroke survivors have difficulty with both precision control of foot placement, as well as reduced control of COM movement. The objective of this dissertation was to characterize dynamic balance control strategies during walking in chronic stroke survivors. Additionally, …

Supraspinal Control Of Unilateral Locomotor Performance: An Fmri Study Using A Custom Pedaling Device, Brett Arand

Master's Theses (2009 -)

This study aimed to develop a novel unilateral pedaling device, validate its function, and use it in an fMRI study of bilateral vs. unilateral locomotor control. The new device is MRI compatible and allows for conventional coupled bilateral pedaling, along with decoupled unilateral pedaling. It was designed with an assistance mechanism to simulate the presence of the non-contributing leg while pedaling unilaterally. During coupled bilateral pedaling, the two legs work in unison: while one leg is extending in the downstroke, it provides support to lift the other leg back up as it is flexing in the upstroke. The device uses …

The Use Of A Pylon Mounted Transducer For Investigating The Gait Of Transtibial Amputees, Justin Robert Brink

UNLV Theses, Dissertations, Professional Papers, and Capstones

Two areas of research interest in the design and use of lower limb prosthetic devices are how foot performance varies with design and how prosthesis alignment affects gait. The current study addressed both of these areas through the use of the JR3 triaxial transducer mounted at the base of the socket. The transducer is an innovative form of instrumentation that measures forces and moments at the end of the socket. Traditional measurement of gait uses a force plate buried in the floor of a gait laboratory. The study established that the transducer offers a viable means of instrumentation for amputee …

Development Of A Muscle Force Optimization Algorithm To Improve Center Of Pressure During Simulated Walking, Lawrence Dean Noble

ETD Archive

The Universal Musculoskeletal Simulator (UMS) was developed at the Cleveland Clinic to facilitate general purpose orthopaedic research that allows investigators to study the in vitro forces applied to bones, tendons and ligaments during simulated exercise of cadaver joint systems. In its original state, the UMS hardware consisted of a rotopod (a specialized hexapod robot), a single rotary tendon actuator and custom LabVIEW software for coordinated control and operation of the system. The focus of this work was to 1) enhance the UMS with a multi-tendon actuator system, 2) develop a muscle force optimization algorithm and evaluate it with a static …

Relationship Between Arch Height And Midfoot Joint Pressures During Gait, Dong Gil Lee

ETD Archive

A foot arch is a multi-segmented curved structure which acts as a spring during locomotion. It is well known that ligaments are important components contributing to this spring-like property of the arch. In addition, intrinsic and extrinsic foot muscles contribute to arch support. According to the windlass foot model, arch height and midfoot joint orientation change during gait. However, it is not known whether altered joint configurations result in increased joint stress during gait. If so, it is possible for there to be a "vicious cycle" in which joint stress increases as the arch height diminishes, which may then lead …