The primary objective of this study was to investigate the usage of Pushrim Activated Power Assist Wheelchairs (PAPAW) among individuals with cervical level spinal cord injuries (tetraplegia) in real-life environments. Fifteen full-time manual wheelchair users with tetraplegia completed a four-week trial including a two-week own wheelchair trial and a two-week PAPAW trial where both the PAPAW provided and personal wheelchairs were tracked. The order of wheelchair use was randomized. Throughout the study period both the PAPAW and participants personal chairs were equipped with a data logging device, which collects time stamps at each wheel rotation. The PAPAWs used in this study were equipped with the JWII (Yamaha Motor Corporation). Participants were asked to daily complete a take home questionnaire with questions regarding type of wheelchair used, places visited, methods of transporting the wheelchair, obstacles preventing travel outside the home, and satisfaction and dissatisfaction with the PAPAW. At the end of each two-week trial, the Psychosocial Impact of Assistive Devices (PIADS) survey was conducted to assess the effects of the PAPAW and the personal chair on users competence, adaptability, and self-esteem. Data logging device analyzed variables included the average daily distance traveled, average speed and the actual daily driving time. Results from this phase showed that participants used the PAPAW significantly more than their personal wheelchairs in the two-week PAPAW trial, indicating that PAPAWs might improve functional independence as well as community participation of individuals with tetraplegia. Overall benefits of the PAPAW reported by participants included easy propulsion, increased independence, and good performance in difficult terrains, increased quality of life, faster speed, and decreased upper-limb pain. Limitations reported included difficult drive wheels disassembling and transportation.

75 subjects, 52 HIV+ and 23 HIV- but considering themselves to be at risk for HIV, completed a psychosocial interview based on the Structured Clinical Interview for DSM-IV (SCID), the Patients Assessment of Own Functioning (PAOF) questionnaire, and a battery of neuropsychological tests. Subjects were then categorized into one of three clinical impairment groups and one of three self-reported impairment groups. Based upon the differences between their clinical impairment group and self-reported impairment group, subjects were classified as being aware, having limited awareness, or having poor awareness. Factors correlated with deficits in awareness included age and performance on the Digit Symbol test and a test of simple reaction time. In addition, those with more severe cognitive impairment were less aware than those who were normal or borderline. A one-way ANOVA suggested that the poor awareness group differed significantly from both the aware and limited awareness groups on the Digit Symbol test and the Rey Figure Immediate and Delayed Recall. The aware and limited awareness groups were not significantly different for any factor. Overall, poor awareness was associated with poorer test performance. In those with HIV/AIDS, age was inversely related to self-awareness, with those who were older and impaired demonstrating better awareness than those who were younger and impaired. This research has implications for understanding poor awareness in HIV/AIDS and for creating appropriate and effective rehabilitation plans.

The Pediatric Adjustable Lightweight Modular (PALM) wheelchair project consisted of three design iterations, full-scale working prototypes, durability testing and user evaluation, and technology transfer activities. User input was crucial to developing design requirements. A handful of concepts developed for this design are novel in the wheelchair market and potentially beneficial to pediatric wheelchair users and their caregivers. Some of the concepts could be applied to other wheelchair designs in the future, including adult tilt-in-space wheelchairs and seating for both adults and children. The PALMs primary construction consists of modular plastic injection molded components and straight tubes. This feature allows it to be easily customized on site by a therapist who can swap components and make adjustments. The modular design also allows it to be packed more compactly thereby decreasing manufacturing and shipping costs. Second, the tilt-in-space mechanism utilizes a unique four-bar linkage design that decreases the need for small moving parts such as rollers and spring loaded mechanisms used in other tilt-in-space center-of-gravity chairs. Third, the PALMs modular design allows for greater flexibility in the configuration of the wheelchair and adaptation to different-sized bodies. Fourth, the PALM is highly adjustable and selectable: The seat depth, seat width, back rest height, back rest angle, leg rest angle, footrest angle, seat-to-floor height, and axle position are all adjustable. Finally, the PALM converts from an attendant-style wheelchair to a self-propelled wheelchair. These features create a variety of characteristics that clearly distinguish the PALM from other currently available pediatric wheelchairs.

Computers provide an interface to the world for many individuals with disabilities and without effective computer access, quality of life may be severely diminished. As a result of this dependence, optimal human computer interaction (HCI) between a user and their computer is of paramount importance. Optimal HCI for individuals with disabilities relies on both the existence of products which provide the desired functionality and the selection of appropriate products and training methods for a given individual. From a product availability standpoint, optimal HCI often depends on modeling techniques used during the development process to evaluate a design, assess usability and predict performance. Computer access evaluations are often too brief in duration and depend on the products present at the site of the evaluation. Models could assist clinicians in dealing with the problems of limited time with clients, limited products for the client to trial, and the seemingly unlimited system configurations available with many potential solutions. Current HCI modeling techniques have been developed and applied to the performance of able-bodied individuals. Research concerning modeling performance for individuals with disabilities has been limited. This study explores HCI as it applies to both able-bodied and individuals with disabilities. Eleven participants (5 able-bodied / 6 with disabilities) were recruited and asked to transcribe sentences presented by a text entry interface supporting word prediction with the use of an on-screen keyboard while time stamped keystroke and eye fixation data was collected. Data was examined to identify sequences of behavior, performance changes based on experience, and performance differences between able-bodied and participants with disabilities. The feasibility of creating models based on the collected data was explored. A modeling technique must support selection from multiple sequences of behavior to perform a particular type of action and variation in execution time for primitive operations in addition to handling errors. The primary contributions made by this study were knowledge gained relative to the design of the test bench and experimental protocol.

The underlying risk factors for female anterior cruciate ligament (ACL) injuries are likely multifactorial. Poor neuromuscular and biomechanical control of the lower limb appears to be a primary contributor to the female ACL injury mechanism. Neuromuscular and biomechanical characteristics of the hip may significantly contribute to lower extremity function, since hip position and motion has been found to influence knee position and loads. Afferent proprioceptive signals from mechanoreceptors in the ACL play a vital role in dynamic joint stability of the knee. The same principle is valid for maintaining dynamic stability of the hip, however there has been limited research examining proprioception of the hip. Prior to investigating the contribution of hip proprioception to knee injuries, the reliability and precision of the desired hip proprioception methods must be established. The goal of this study was to establish the intersession and intrasession reliability and precision of threshold to detect passive motion, force sense and active joint position sense tests of the hip in healthy individuals. The results of this study indicate that a reliable and precise method of measuring hip threshold to detect passive motion (TTDPM) has been established. Further investigation is warranted to develop reliable and precise measurement methods for force sense (FS) and active joint position sense (JPS) measurements of the hip.

Pressure ulcers have long been an important healthcare issue in both acute and long-term care settings. Temperature is one of the extrinsic causative factors for this multi-factorial disease not yet fully explored. Previous animal studies revealed that skin cooling reduced the severity of ulceration compared to non-cooling. Cooling is also used widely in plastic surgery and organ transplants for tissue preservation. However, the underlying protective mechanism of local cooling remains unclear. Our studys objective was to measure the effect of cooling on tissues response to pressure using skin perfusion response on human subjects. Reactive hyperemia is a normal protective physiological response occurring after vessel occlusion. Laser Doppler flowmetrey was used to measure cutaneous perfusion. We hypothesized that local cooling would reduce a rigid indenter induced post-ischemic reactive hyperemic response. Ten young healthy non-smokers were recruited into the study. A repeated measures design was used where all subjects were subjected to pressure with cooling to 25°C and pressure without cooling test sessions. Each test session contained five levels of pressure control: light contact (10 minutes), 60 mmHg (30 minutes), light contact (20 minutes), 150 mmHg (3 minutes), light contact (10 minutes). The cooling intervention was performed during the period of 60mmHg contact pressure. Our results showed a significantly attenuated peak perfusion response after 60mmHg (p=0.019) but not after 150mmHg (p=0.241) of pressure for the cooling session compared to the non-cooling. This study suggests that local cooling may protect skin from the harmful effects of prolonged pressure in this young healthy population. The study protocol would be modified to investigate populations at risk of pressure ulcers.

Currently, about 13% of the population ages 21-64 have a disability in the United States and approximately 1.7 million of people use a wheelchair for their mobility needs. Additionally, over 100,000 individuals in the United States use an electric-powered wheelchairs and the use of power wheelchairs has been associated with increased opportunities to participate in society for individuals with mobility disabilities. While assistive devices have facilitated participation, barriers still exist. Approximately 30% of individuals with disabilities reported facing difficulties in accessing transportation compared to 10% of individuals without disabilities and transportation was reported as the most significant barrier related to their work environment. Furthermore, the national employment rate for individuals with disabilities age 21-64 is roughly 38% while the rate of individuals without disabilities is about 80%. The main objective of this study was to collect data from individuals who use power wheelchairs or scooters. Data were collected and analyzed on variables of transportation barriers, employment, community integration, and health related quality of life. One hundred and two individuals consented to participate in this study. Significant correlations were found between health related quality of life and community integration scores (Community Integration Questionnaire). Individuals who are employed have a significantly better HRQoL than individuals who are unemployed. No significant differences were found on the basis of self-reported transportation difficulties. Employment rates for persons who use power wheelchairs are related to the individuals health related quality of life. While previous research has shown that independent transportation is essential to employment for persons with disabilities, this study has shown that individuals who do not experience self-reported transportation difficulties have no difference in employment rates than individuals who experience transportation difficulties.

A series of commercially available titanium ultralight wheelchairs were tested using ANSI/RESNA testing procedures, and their durability was compared with previously tested aluminum ultralight wheelchairs and light-weight wheelchairs. Three of each of the following titanium wheelchairs were tested: Invacare-TopEnd, Invacare-A4, Quickie-Ti, and TiLite-ZRA. The Quickie-Ti wheelchairs had the most forward and rearward center of gravity adjustability. All of the titanium wheelchairs passed the forward braking effectiveness test, but two chairs of each model tipped backward before the platform inclining to 7 degree in the rearward braking effectiveness test. All titanium wheelchairs passed the impact strength tests, but two failed in the static strength tests: two Invacare-TopEnd wheelchairs and one Invacare-A4 wheelchair failed due to deformation of the armrest mounting plates, and the handgrips of the TiLite-ZRA wheelchairs slid off the push handles. Two Invacare-A4 and one Invacare-TopEnd successfully completed the double drum and curb drop tests, but the remaining 9 wheelchairs failed prematurely. No significant differences were found in the number of the equivalent cycles or the value among the four models. The titanium ultralight wheelchairs had less equivalent cycles and value than the aluminum ultralight wheelchairs that were tested in a previous study. The failure modes in the static strength tests and the fatigue tests were consistent within the model, and revealed important design issues for each model. Our results suggest that manufacturers need to perform more careful analyses before commercializing new products.

People with Cerebral Palsy (CP) have difficulty using computer pointing devices due to unintentional movement in their upper extremities. Fifty percent of people with CP have impaired arm-hand function which limits their ability to interface with pointing devices and effectively control cursor movement on the computer screen. This thesis involves two studies which utilize an Isometric Joystick in order to access the computer and complete target acquisition tasks. The first study titled Quantification of Cursor Movement of People with Athetoid and Spastic Cerebral Palsy to Improve Target Acquisition, aims to guide real-time digital filter development for people with athetoid and spastic CP for target acquisition tasks. By investigating the cursor movement measures throughout the target acquisition trajectory we gained a better insight as to when and how to compensate for unintentional movement in people with CP. Results showed that both people with athetoid CP and spastic CP have more difficulty hovering over the target than they did moving to the target, indicating that filter development should focus on the hovering portion of the target acquisition task in order to improve target acquisition time. The second study titled Customized Control for People with Athetosis and Dystonia to Improve Computer Access, aims to develop a method to prescribe appropriate switch/scanning control for people with athetosis and dystonia as well as to determine if customized switch/scanning control is more effective in completing icon selection tasks than the proportional isometric control. Results of this study suggest that switch/scanning control could be useful in moving on the most direct path to the target as shown by a significantly smaller percent distance error for customized control as compared to proportional isometric control (F(1,6) = 361.2, p < 0.01).

Current assistive technology (AT) provision efforts in less-resourced environments rely on heuristic methods to monitor and improve service provision, instead of evidence-based practice (EBP) which has become standard in well-resourced regions. To introduce EBP methods, and evaluate the impact of technology on the lives of people with disabilities, we collaborated with clinicians at the Indian Spinal Injuries Centre (ISIC). Two studies were conducted using ISIC quality assurance data collected with our assistance. Based on our experience at ISIC, a third study was performed to investigate the challenges to international AT research, and develop strategies to overcome these challenges. The first study was conducted with individuals receiving new AT from ISIC. The data consisted of a baseline PART survey and 6-month and 12-month follow-ups taken with a majority (92%) outpatient population. Thirteen clients completed all three questionnaires. Results showed trends toward increased community participation and life satisfaction over the 12-month period. ISIC is planning to expand its implementation of the PART survey, perhaps online. The second study was conducted with individuals (69% inpatient) who received new wheelchairs from ISIC. The Wheelchair Skills Test and QUEST were administered before and after personal wheelchair provision. Seven clients completed a full set of pre- and post-tests. Trends toward increased skill completion rates, increased skill attempt rates, and slightly increased safety scores were found. QUEST scores increased in the post-test, bringing scores close to values reported in literature. The third study, conducted using a three-round Delphi method online, involved the participation of 13 experts in AT and rehabilitation research with experience working in low- and middle-income countries. During the first questionnaire round, participants were asked to identify domains of research that they considered the most challenging. In the second round, they were asked to rank and categorize the challenges as being either ethical or logistical, and also to suggest strategies to address them. In the final round, participants were asked to critique each strategy on its efficacy. Topics discussed included local collaboration, appropriate tools and techniques, translation, retention, compensation, and funding. Verifying the efficacy of suggested strategies could be the subject of future research.