Engineering Commons^™

Biomechanical Analysis Of Open-Skull High-Rate Traumatic Brain Injury Using Finite Element Mouse Brain Model, Lihong Lu

Electronic Thesis and Dissertation Repository

To better understand traumatic brain injury (TBI), it is necessary to correlate with injuries, which are observed from in vivo laboratory experiments, to brain mechanical responses, which can so far be best predicted by finite element (FE) models. Firstly, a previously validated FE model was improved to investigate the effect of repeated impacts and lateral movements on brain responses to ensure the accuracy and reproducibility of controlled cortical impact (CCI) across different labs. Then, a new FE mouse brain model with the detailed three-dimensional (3D), non-linear vasculature was developed to study how the vasculature affected brain response in CCI and …

A Heterogeneous Patient-Specific Biomechanical Model Of The Lung For Tumor Motion Compensation And Effective Lung Radiation Therapy Planning, Parya Jafari

Electronic Thesis and Dissertation Repository

Radiation therapy is a main component of treatment for many lung cancer patients. However, the respiratory motion can cause inaccuracies in radiation delivery that can lead to treatment complications. In addition, the radiation-induced damage to healthy tissue limits the effectiveness of radiation treatment. Motion management methods have been developed to increase the accuracy of radiation delivery, and functional avoidance treatment planning has emerged to help reduce the chances of radiation-induced toxicity. In this work, we have developed biomechanical model-based techniques for tumor motion estimation, as well as lung functional imaging. The proposed biomechanical model accurately estimates lung and tumor motion/deformation …

In Vitro Biomechanical Analyses Of The Pcl And Medial Ligaments Of The Human Knee, Alireza Moslemian

Electronic Thesis and Dissertation Repository

Previous studies have shown that surgical treatments of PCL injuries are not successful in all cases and there is room for improvement. The effectiveness of an isolated PCL reconstruction, in the setting of what actually is a multi-ligament injury, may be inadequate, and therefore the biomechanical contribution of other ligaments in a PCL-deficient knee need to be better understood.

A new apparatus was used to analyze the effect of medial ligaments transection on the kinematics of the PCL-deficient knee during simulated clinical tests and activities of daily living. We observed that the anterior translation of the medial side of the …

A Novel Method For In Vivo Evaluation Of Finger Kinematics For Analysis Of Activities Of Daily Living, Ahmed M. Tanashi

Electronic Thesis and Dissertation Repository

This thesis examines the development of a six degrees of freedom finger coordinate system that employs electromagnetic tracking to measure finger kinematics. Secondarily, this thesis validated the in vivo finger coordinate system, and is then used to examine range of motion in the fingers in patients with hand osteoarthritis. Lastly, this thesis examines the range of motion of individuals with and without hand arthritis during various activities of daily living, performed with and with joint protection program principles. This study presents a foundation for finger kinematic evaluation and describes a methodology that will be used for larger studies to be …

The Effect Of Radial Head Hemiarthroplasty Stem Fit On Radiocapitellar Contact Mechanics: Is Loose Fit Better Than Rigidly Fixed?, Jakub Szmit, Graham J.W. King, James A. Johnson, G. Daniel G. Langohr

Western Research Forum

Background/Methods: Radial head hemiarthroplasty is commonly employed to manage comminuted displaced fractures. With regards to implant fixation, current designs vary with some prostheses aiming to achieve a tight 'fixed' fit, and others utilizing a smooth stem with an over reamed 'loose' fit. The purpose of the present study was to evaluate the effect of radial head hemiarthroplasty stem fit on radiocapitellar contact using a finite element model which simulated both fixed (size-for-size) and loose (1, 2 & 3mm over reamed) stem fits.

Hypothesis: It was hypothesized that a loose stem fit would improve radiocapitellar contact mechanics, with increased contact area …

Investigating The Effect Of Stiffness In Hemiarthroplasty Implants, Carolyn Berkmortel, Daniel Langohr, Graham King, James Johnson

Western Research Forum

Background: Hemiarthroplasty is an attractive alternative to total arthroplasty because it conserves tissue, allows for quicker recovery, and has a lower cost. However, likely due to the high stiffness of the implant, hemiarthroplasties often lead to accelerated wear of the opposing native cartilage.

Hypothesis and Methods: The purpose of this study was to investigate the maximum contact stress on the capitellum for different currently available biomaterials in radial head hemiarthroplasty and compare them to the native radial head. A finite element model was developed in ABAQUS (Dassault Systèmes Simulia Corp., RI, USA). An axial load of 100N was applied to …

Investigating Grip Range Of Motion And Force Exerted By Individuals With And Without Hand Arthritis During Functional Tasks And While Swinging A Golf Club, Sara Frances Holland

Electronic Thesis and Dissertation Repository

Hand arthritis is the leading cause of disability in individuals over the age of 50; resulting in dysfunction and pain, making activities of daily living and recreational activities such as golf difficult. Few studies have been conducted on the biomechanical response of individuals with hand arthritis when performing functional activities. This research quantified hand grip movements and strength differences seen in individuals with hand arthritis. Using a video-based motion capture system (Dartfish), a grip limitation of 17.2% (maximum flexion), and 12.7% (maximum extension) was discovered. A wireless finger force measurement system (FingerTPS), was used to show that larger diameter, softer …

Graduate Keynote. Golf Grip Force Evaluation In Individuals With And Without Hand Arthritis Using A New Wearable Sensor Technology, Sara Frances Holland, Emily Lalone, Louis M. Ferreira, James P. Dickey

Western Research Forum

BACKGROUND

Hand osteoarthritis (H-OA) is the most common type of osteoarthritis largely affecting individuals over 45. H-OA involves pain, loss of grip strength and limiting participation in recreational activities such as golf. Currently, a number of ‘arthritic’ grips are designed using joint protection principles to ‘reduce hand forces and tight gripping’. However, no comprehensive examinations in their effectiveness have been conducted.

HYPOTHESIS

The purpose of this study is to systematically analyse the hand forces produced from various golf grips and arthritis grips at the distal-phalanges of the hand-grip interface in individuals with and without hand arthritis using new wearable sensor …