In gymnastics, females are often afflicted with lower extremity injuries during the landing phase of a backward rotating skill. The purpose of this study was to assess the efficacy of using a drop landing and backward somersault landing to compare and contrast the kinetic and kinematic differences between the two tasks in order to determine if a drop landing is a suitable representative task to analyze when examining landing injury mechanisms. Eleven female NCAA Division I gymnasts (age 19.3 ± 0.9 yrs; body height 1.66 ± 0.05 m; body mass 61.36 ± 6.02 kg) were recruited to perform drop landings and backward somersaults. Two force plates along with a 3D movement analysis system were used to collect kinetic and kinematic data. A repeated measures ANOVA was used to examine the differences in the variables with the significance level set at 0.05. There were mechanical differences and significance found between the peak vertical ground reaction forces, loading rate, kinetic and kinematic variables in the sagittal and frontal planes during the two tasks. It is evident that results may underestimate the effect of gymnastics landing impacts on risk of lower extremity injury because of the mechanical differences and significance found between the two tasks. / Access to thesis permanently restricted to Ball State community only.

There is little research specifically examining fast-pitch softball pitchers. However of the few studies completed, pitchers have been reported to exhibit a high incidence of injury. How and why these pitchers are suffering from injuries has not been elucidated.The purpose of this study was to investigate the injuries occurring to collegiate softball pitchers and factors that may influence these injuries such as demographic, pitching, training, and injury information.A cross-sectional survey of collegiate softball pitchers from Divisions I, II, and III was conducted using InQsit, a web-based survey system. Instructions on how to complete a web-based survey was sent and completed over a two-week period, by 181 Division I, II, and III collegiate softball pitchers. The survey was composed of questions addressing: 1) demographic information, 2) pitching and game data, 3) training program information, and 4) injury reporting.The results showed that demographic information, pitching and game data, and training were not statistically significant (p<0.05) in relation to injury. Among the 131 reported injuries, 36 were acute, 92 chronic, and 3 unspecified. Of the 92 chronic/overuse injuries, 10 were Grade I, 30 Grade II, 39 Grade III, and 13 Grade IV. Of the total injuries, 80 were a direct result from pitching, with 36 relating to the shoulder and 17 to the lower back. Among the injured pitchers, 109 took Non-Steroidal AntiInflammatory Drugs, 140 used modalities, 11 received surgeries, and 95 saw additional specialists. This study revealed that a high percentage (72.8%) of collegiate pitchers are suffering injuries across the nation and more research focused on this area is needed. In addition, coaches need to continue to be informed of ways they can improve the health and training programs of their pitchers. / School of Physical Education

The relationship between lesion volume in children with traumatic brain injury (TBI) and IQ scores was investigated in this study. Participants included eight children between the ages of 8-12 years with primarily right hemisphere TBIs and 16 normals who were matched based on age and gender. Archival data employing the Wechsler Intelligence Scale for Children - III (WISC-III) scores was the source of Verbal IQ (VIQ), Performance IQ (PIQ), and Full Scale IQ (FSIQ) scores. Severity of injury was determined using the Glasgow Coma Scale (GCS) which was contained in the same archival database. Lesion volume was determined utilizing National Institute of Health (NIH) Image (Version 1.76) and magnetic resonance imaging scans of the injured children. The area of the lesion was outlined, using the freehand line tool, on successive slices, summed, and multiplied by the corresponding acquisition slice gap to obtain a measure of total volume. Results indicated that lesion volume does not explain a significant portion of the variance associated with TBI. Severely injured children had lower IQs than children with mild or no injury. Additionally, children with right hemisphere injuries had significantly lower VIQ, PIQ, and FSIQ scores than normals. Qualitative analyses revealed that lesion volume appears to be related to the change in IQ scores during recovery. Typically, children with larger lesions (e.g., more severe injury) had greater functional losses and had greater gains to make; therefore, they demonstrated greater changes in IQ score as compared to less severely injured children. Predicting the area of deficit based upon lesion location yielded results congruent with chance. Results appear to reinforce the complexity of TBI; no single piece of data explains a significant portion of the variance associated with this phenomenon. Future research should strive toExamine and control for the numerous factors associated with TBI (e.g., age, lesion location, lesion volume, premorbid abilities, parental education, GCS score, gender, use of standard test battery, and many others) within a single study. Efforts to provide optimal treatment and recovery of TBI patients could be informed by such research. / Department of Counseling Psychology and Guidance Services

This study has examined the aspect of psychological care for the injured athlete at the Division 1A collegiate level. The specific areas examined were those of the mental impact of injury, services available, potential barriers, funding, and referrals. An additional aspect of this study that was examined was differences between conferences in the psychological care practices of the injured athlete. It was found that the largest barrier to successful psychological rehabilitation of the injured athlete was athlete compliance, despite support from others and available services. No significant differences were found to exist between conferences and the psychological care of the injured athlete. / School of Physical Education

Since the discovery of peripheral nerve regeneration nearly a century ago, the mechanisms that guide this regeneration have been elusive. This project aimed to describe how an axon is able to traverse the environment of the body and precisely reinnervate its target cell. Using a novel technique of combining light and electron microscopy, I observed reinnervating axons in transgenic mice to answer the questions of whether Schwann cells are an important guidance cue for the motor neuron and whether the outgrowing axon is fully developed or the process is a step-wise process of activation. The data suggests that Schwann cell contact is important for the tip of the regenerating axon to guide the axon back to its synapse on the muscle fiber. Further, it seems that the tip of the axon is not capable of synaptic transmission as it lacks active zones, suggesting that reinnervation is a step-wise process. / Department of Physiology and Health Science

Access to abstract permanently restricted to Ball State community only. / Department of Counseling Psychology and Guidance Services

Satellite cells are quiescent skeletal muscle specific stem cells that are activated in response to injury to aid in muscle repair and regeneration. The interaction of hepatocyte growth factor (HGF) with these cells is crucial for their activation. However, to date, research on the effect of HGF on skeletal muscle satellite cells has yielded conflicting data. Clarity is therefore required as to its effect on downstream myogenic processes. Furthermore, mouse and rat cell lines and primary culture have been widely used for in vitro studies to investigate the effect of HGF on skeletal muscle physiology and disease; very few studies have been carried out in primary cultured human skeletal myoblasts. As a result, we aimed to investigate and compare the effect of HGF (2, 10 and 50 ng/ml) on mouse C2C12 myoblast versus primary culture human skeletal myoblast (HSkM) proliferation, migration and differentiation. Proliferation was assessed via both cell counts and crystal violet assay, while migration was investigated using the scratch assay. Differentiation was determined via analysis of expression patterns of transcription factors implicated in myogenic commitment (i.e. Pax7, MyoD) as well expression of the structural protein Myosin Heavy Chain (MyHC). We demonstrate a dose-dependent effect of HGF on myoblast proliferation whereby an increase in proliferation was detected in response to 2 ng/ml HGF, whilst 10 ng/ml HGF resulted in a reduction in proliferation capacity of both C2C12 and HSkM myoblasts. Interestingly, the reduction in proliferation in response to 10 ng/ml HGF was accompanied by a down-regulation in Pax7 expression during differentiation of both mouse and human myoblasts. HGF also affected myoblast migration and differentiation in a dose-dependent manner that was inversely proportional to proliferation. HGF (10 ng/ml) stimulated an increase in myogenic commitment and terminal differentiation of C2C12 and HSkM myoblasts as reflected by the increased percentage MyoD positive cells, improved fusion and greater MyHC expression. C2C12 myoblast migration was also stimulated at this HGF concentration, but reduced in response to the lower HGF (2 ng/ml) dose. The decrease in proliferation following incubation with 10 ng/ml HGF, allows cells to exit proliferation into either a mode of migration or differentiation. Our data confirms the importance of HGF during myogenesis and highlights the sensitivity of satellite cells to changing HGF concentration. This has implications in the regulation of skeletal muscle wound repair. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.

Injury to the central nervous system (CNS) results in the formation of a highly inhibitory glial scar consisting mainly of chondroitin sulfate proteoglycans (CSPGs). CSPGs are comprised of a protein core with covalently attached chondroitin sulfate glycosaminoglycan (CS-GAG) side chains. CSPGs and CS-GAGs have been implicated in the regenerative failure of the CNS, though the mechanism underlying inhibition is unclear. Sulfation affects both the physical and chemical characteristics of CS-GAGs and, therefore, it has been hypothesized that certain sulfation patterns are more inhibitory than others. To investigate this hypothesis, specific chondroitin sulfate sulfotransferases (CSSTs), the enzymes responsible for CS-GAG sulfation, were knocked down in vitro using siRNA. C4ST-1, C4ST-2, and C46ST were chosen as targets for gene knockdown in this study based on their expression in neural tissue and the extent of inhibition caused by their respective CS-GAG. It was hypothesized that transfection of primary rat astrocytes with siRNAs designed to prevent the expression of C4ST-1, C4ST-2, and C46ST would decrease specific sulfation patterns of CSPGs, resulting in improved neurite extension in a neurite guidance assay. Through optimization of siRNA dose, astrocyte viability was maintained while successfully knocking down mRNA levels of C4ST-1, C4ST-2, and C46ST and significantly reducing total levels of secreted CS-GAGs. However, no increase in the incidence of neurite extension was observed using conditioned media collected from siRNA transfected astrocytes compared to non-transfected controls. These data suggest that sulfation does not contribute to CSPG-mediated neurite inhibition, though further investigation is necessary to confirm these findings. Significantly, this work has established a paradigm for investigating the role of CSPG sulfation patterns in CNS regeneration.

Access to and subsequent control of spinal cord function are critical considerations for design of optimal therapeutic strategies for SCI patients. Electrical stimulation of the spinal cord is capable of activating behaviorally-relevant populations of neurons for recovery of function, and is therefore an attractive target for potential devices. A promising method for accessing these spinal circuits is through their axons, which are organized as longitudinal columns of white matter funiculi along the cord exterior. For this thesis, I hypothesized that these funiculi can be selectively recruited via electrodes appropriately placed on the surface of the spinal cord, for functional activation of relevant motor circuitry in a chronically-transected spinal cord. My tandem design goal was to fabricate and implement a conformable multi-electrode array (MEA) that would enable this selective stimulation. To accomplish this design goal, I participated in the design, fabrication, and electromechanical testing of a conformable MEA for surface stimulation of spinal tracts. I then assessed the fundamental capability of this MEA technology to stimulate white matter tracts in a precise, controlled, and functionally-relevant manner. This was accomplished via in vitro experiments that explored the ability of this MEA to locally activate axons via single- and dual-site surface stimulation. The results from these evaluation studies suggest that spinal-cord surface stimulation with this novel MEA technology can provide discrete, minimally-damaging activation of spinal systems via their white matter tracts. To test my hypothesis that surface stimulation can be used to recruit distinct populations in the spinal cord, I performed studies that stimulated lateral funiculi in both chronically-transected and intact in vitro spinal cords. Results from these studies reveal that selective surface stimulation of white matter tracts in the ventrolateral funiculus (VLF) elicit motor outputs not elicited in intact cords. In addition, I was able to demonstrate that the spinal systems activated by this surface stimulation involve synaptic components and are responsive to spatial, temporal, and pharmacologic facilitation. Corresponding labeling of the axonal tracts projecting through the T12 VLF indicate that, after chronic transection, the remaining spinal neurons whose axons travel through the VLF include those with cell bodies in both the intermediate region and dorsal horn. These electrophysiological results show that surface-stimulating technologies used to control motor function after injury should include focal activation of interneuronal systems with axons in the ventrolateral funiculus. As a whole, these studies provide essential starting points for further use of conformable MEAs to effectively activate and control spinal cord function from the surface of the spinal cord.

"This research aimed to explore and better understand intervention protocols and their effect on lower limb control associated with anterior cruciate ligament (ACL) injury. A fundamental and unique aspect of this investigation was to establish a lab-based testing protocol that successfully mimicked actual game play. [...]This research validated a lab-based measure that best mimicked game-play to use as a pre- and post- testing measure for two common methods used in current ACL intervention strategies. In addition, further understanding of the effects of a landing training and dynamic balance training program were found." / Doctor of Philosphy