Biomedical Engineering and Bioengineering Commons^™

A Multimodal Approach To Investigate Brain Reorganization After Spinal Cord Injury Using Functional Magnetic Resonance Imaging And Functional Near-Infrared Spectroscopy, Keerthana Deepti Karunakaran

Dissertations

Traumatic Spinal Cord Injury (SCI) results in structural and functional neurological changes at both the brain and the level of the spinal cord. Anatomical studies indicate decreased grey matter volume in sensorimotor and non-sensorimotor regions of the cortex following SCI; whereas, neurophysiological findings mostly report altered functional activity in the sensorimotor nodes of the cortex, subcortex, and cerebellum. Therefore, it is currently unknown whether tissue atrophy observed in non-motor related areas has any concomitant functional consequences. Furthermore, the neural underpinnings of adaptive neuroplasticity after SCI is not well-defined in the current literature. Hence, this dissertation is a pioneer study investigating …

Hand Control Of Bipedal Balance In Quiet Standing: Implementations For Lower Extremity Exoskeleton, Ala’A Al-Rashdan

Dissertations

Maintaining stable posture is important for humans, even though it is challenging because of our bipedal structure. One of the main balance related disorders is paraplegia due to spinal cord injury. People with a complete spinal cord injury have motor and sensory impairment that greatly reduces the ability to move their lower extremities. In recent years, lower extremity exoskeletons that apply torques generated by motors to the joints of the person have helped to them stand and walk.

This research is a part of an extended project to build a new exoskeleton for use by individuals with paraplegia due to …

Construction And Assessment Of A Computer Graphics-Based Model For Wheelchair Propulsion, Brooke Marie Odle

Dissertations

Upper limb overuse injuries are common in manual wheelchair using persons with spinal cord injury (SCI), especially those with tetraplegia. Biomechanical analyses involving kinetics, kinematics, and muscle mechanics provide an opportunity to identify modifiable risk factors associated with wheelchair propulsion and upper limb overuse injuries that may be used toward developing prevention and treatment interventions. However, these analyses are limited because they cannot estimate muscle forces in vivo. Patient-specific computer graphics-based models have enhanced biomechanical analyses by determining in vivo estimates of shoulder muscle and joint contact forces. Current models do not include deep shoulder muscles. Also, patient-specific models …

Alterations In Brain Connectivity After Spinal Cord Injury Using Functional Mri, Yamin Ahmed Noor

Theses

Every year, approximately 50 people per million of inhabitants are inflicted by Spinal Cord Injury (SCI). The long-term impairment of the SCI patients has led researchers to investigate different rehabilitation and treatment efforts that require careful observations to be made on reliable markers. Presently, a number of neuropsychological assessments are used for SCI rehabilitation and research purposes. However, there is a need for the discovery of sensitive biomarkers that can be used to characterize SCI. Altered functional connectivity in the brain has been observed in a number of neurological patient populations. Hence, it was hypothesized that such alterations in brain …

Assessing Trainer Hand Forces For Manual Body Weight Supported Walking, Manish Raval

Theses

Spinal cord injuries occur in approximately 12,000 to 15,000 people per year in the U.S. About 10,000 of these people are permanently paralyzed. Most spinal cord traumas occur in young, healthy individuals. Males between 15 and 35 years old are most commonly affected.

Recently new approaches to facilitate walking recovery for individuals after a spinal cord injury, have been directed towards a therapy known as Locomotor Training (LT) that implements repetitive stepping on a treadmill using body weight support. A major intent of LT research is to investigate the effect of an extended period of LT on bilateral muscle activation …

Design Of Three-Dimensional Axon Stretch Growth Device, Fayekah Assanah

Theses

Spinal Cord Injury (SCI) causes destruction and degeneration of axons in the white matter of the spinal cord, resulting in functional loss and paralysis. A successful treatment of SCI requires axons to regenerate across damaged regions. Current studies focus on identifying mechanisms to promote axon regeneration in lesions and have yet to be successful in preventing nerve degeneration due to scar tissue formation. Establishing axonal bridges over long distances of SCI lesions remains a challenge, resulting in poor functional recovery. Instead of relying on promoting axon regeneration into lesions, Pfister et al. has developed a transplantable nervous tissue construct spanned …

The Extraction Of Type 1 Collagen And The Fabrication Of Multi-Filament Embedded Hydrogels For Guided Nerve Regeneration, Mevan Lakmal Siriwardane

Theses

Each year, there are approximately 11,000 new cases of spinal cord injury (SCI) in the United States [2]. There have been some success in pre-clinical studies to induce axonal generation, but the reconnection of axons over large distances remains the greatest challenge. Since the development of nerve conduit to facilitate general axonal regeneration, the primary focus has changed to directing the regeneration of axons while also promoting their outgrowth over very extensive lesions to ensure functional recovery of transected nerves during in vitro experiments by using natural materials such as type I collagen, which is the largest constituent of the …