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Comfortable propulsion and support, light weight, and small dimensions are important features that help preserve upper-limb integrity of manual wheelchair users and improve accessibility. The titanium wheelchair is a product developed in response to these goals, but none of the test results of titanium wheelchairs had been disclosed before this study was performed. We hypothesized that these titanium wheelchairs would be in compliance with American National Standards Institute (ANSI)/Rehabilitation Engineering and Assistive Technology Society of North America (RESNA) standards. We tested 12 ultralight titanium rigid-frame wheelchairs (4 models) using ANSI/RESNA testing procedures and compared the test results with previously tested ultralight and lightweight aluminum wheelchairs. All wheelchairs passed the forward braking effectiveness test, but eight wheelchairs tipped backward before inclining to 7 degrees in the rearward braking effectiveness test. All wheelchairs passed the impact strength tests, but six wheelchairs failed in the static strength tests. Three wheelchairs successfully completed the fatigue tests, but the remaining wheelchairs failed prematurely. This group of titanium wheelchairs had less equivalent cycles and value than the ultralight aluminum wheelchairs that were tested in a previous study. The failure modes revealed important design issues of each model. Our results suggest that manufacturers may need to perform more careful analyses before commercializing new products. [ABSTRACT FROM AUTHOR]

The objective of this study was to conduct a kinetic analysis of manual wheelchair propulsion during start-up on select indoor and outdoor surfaces. Eleven manual wheelchairs were fitted with a SMART[Wheel] and their users were asked to push on a course consisting of high- and low-pile carpet, indoor tile, interlocking concrete payers, smooth level concrete, grass, hardwood flooring, and a sidewalk with a 5-degree grade. Peak resultant force, wheel torque, mechanical effective force, and maximum resultant force rate of rise were analyzed during startup for each surface and normalized relative to their steady-state values on the smooth level concrete. Additional variables included peak velocity, distance traveled, and number of strokes in the first 5 s of the trial. We compared biomechanical data between surfaces using repeated-measures mixed models and paired comparisons with a Bonferroni adjustment. Applied resultant force (p = 0.0154), wheel torque (p < 0.0001), and mechanical effective force (p = 0.0047) were significantly different between surfaces. The kinetic values for grass, interlocking payers, and ramp ascent were typically higher compared with tile, wood, smooth level concrete, and high- and low-pile carpet. Users were found to travel shorter distances up the ramp and across grass (p < 0.0025) and had a higher stroke count on the ramp (p = 0.0124). While peak velocity was not statistically different, average velocity was slower for the ramp and grass, which indicates greater wheelchair/user deceleration between strokes. The differences noted between surfaces highlight the importance of evaluating wheelchair propulsion ability over a range of surfaces. [ABSTRACT FROM AUTHOR]

A walker that could help navigate and avoid collisions with obstacles could help reduce health costs and increase the quality of care and independence of thousands of people. This study evaluated the safety and performance of the Veterans Affairs Personal Adaptive Mobility Aid (VA-PAMAID). We performed engineering tests on the VA-PAMAID to determine safety factors, including stability, energy consumption, fatigue life, and sensor and control malfunctions. The VA-PAMAID traveled 10.9 km on a full charge and avoided obstacles while traveling at a speed of up to 1.2 m/s. No failures occurred during static stability, climatic, or fatigue testing. Some problems were encountered during obstacle climbing and sensor and control testing. The VA-PAMAID has good range, has adequate reaction time, and is structurally sound. Clinical trials are planned to compare the device to other low-technical adaptive mobility devices. [ABSTRACT FROM AUTHOR]

The primary objective of this study was to examine the kinematics and kinetics of the shoulder during wheelchair propulsion at a slow and moderate speed. Twenty-seven individuals with paraplegia propelled their wheelchairs at speeds of 0.9 m/s and 1.8 m/s while a motion analysis system captured movements of their upper limbs and SMARTWheels simultaneously recorded their pushrim kinetics. Intraclass R correlation and Cronbach's coefficient alpha statistics revealed that all shoulder parameters were stable and consistent between strokes and speeds. The shoulder exhibited a greater range of motion, and forces and moments at the shoulder were 1.2 to 2.0 times greater (p < 0.05) during the 1.8 m/s speed trial. Peak posterior forces occurred near the end of the propulsion phase, and at the same time, the shoulder was maximally flexed and minimally abducted (p > 0.1). Shoulder positioning and the associated peak shoulder loads during propulsion may be important indicators for identifying manual wheelchair users at risk for developing shoulder pain and injury. [ABSTRACT FROM AUTHOR]

Wheelchair locomotion is an important form of mobility for many individuals with spinal cord injury. However, manual wheelchair propulsion can lead to upper-limb pain and can be very inefficient. This has led investigators to apply biomechanics to the study of wheelchair use. The objectives of this study were (1) to determine the frequency content of the motion of both hands during two speeds of wheelchair propulsion, (2) to obtain the filter frequencies necessary to remove noise from wheelchair motion data, and (3) to provide signal-to-noise ratio data for wheelchair kinematics. The participants in this study were a random sample of manual wheelchair users with paraplegia caused by spinal cord injury. Subjects propelled their personal wheelchairs on a computer-controlled dynamometer at speeds of 0.9 m/s and 1.8 m/s. Motion data were collected at 60 Hz with the use of a commercial infrared marker-based system. The main outcome measures were arm motions and noise frequency spectra, filter cutoff frequencies, and signal-to-noise ratio. Our results indicate that there is no useful signal power above 6 Hz during manual wheelchair propulsion at the speeds that we analyzed. In many cases, there was no useful signal power above 4 Hz. This would indicate that the frequency content of manual wheelchair propulsion is similar to that of human gait. The mean signal-to-noise ratio varied from a high of 91 dB to a low of 21.8 dB. The signal-to-noise ratio was greatest in the x direction (along the line of progression) and lowest in the z direction (medial-lateral). Manual wheelchair propulsion kinematic data should be low-pass filtered at approximately 6 Hz for speeds at or below 1.8 m/s. The data presented in the archival literature appear to have been filtered at an appropriate frequency. [ABSTRACT FROM AUTHOR]

Little is known about how dynamic acceleration affects wheelchair-rider comfort. The current study was to test both the operation of an instrumented wheelchair by a wheelchair user over a Simulated Road Course (SRC) and the operation of the same instrumented wheelchair during normal daily activities (a field test) by test subjects. Sixteen subjects participated in the protocol. A SRC allowed collection of data from wheelchair users traversing obstacles similar to those experienced by a typical wheelchair user. The SRC consisted of eight obstacles fixed rigidly to a flat concrete surface. The field test began after the conclusion of the SRC test. Transfer functions were derived for all 16 subjects. It is clear from the results that for the SRC, the acceleration at the wheelchair frame exceeded the 8-h 'fatigue-decreased performance boundary.' A vertical acceleration resonant peak was evident for eight of the subjects. The average for these peaks, when present, was 8.1 Hz. This frequency is higher than the 4-6 Hz resonant peak presented in the literature for a seated human subject. This discrepancy could be due to different levels of trunk control between wheelchair users in this study and ambulatory subjects used in the literature. Subjects and their wheelchairs were exposed to a few, high-acceleration events rather than consistent, small-magnitude accelerations during the field test. This study indicates that vibration may be a contributing factor to fatigue among manual wheelchair users, which could lead to injury. [ABSTRACT FROM AUTHOR]

The inertia and resistance of a wheelchair dynamometer must be determined in order to compare the results of one study to another, independent of the type of device used. The purpose of this study was to describe and implement a dynamic calibration test for characterizing the electro-mechanical properties of a dynamometer. The inertia, the viscous friction, the kinetic friction, the motor back-electromotive force constant, and the motor constant were calculated using three different methods. The methodology based on a dynamic calibration test along with a nonlinear regression analysis produced the best results. The coefficient of determination comparing the dynamometer model output to the measured angular velocity and torque was 0.999 for a ramp input and 0.989 for a sinusoidal input. The inertia and resistance were determined for the rollers and the wheelchair wheels. The calculation of the electro-mechanical parameters allows for the complete description of the propulsive torque produced by an individual, given only the angular velocity and acceleration. The measurement of the electro-mechanical properties of the dynamometer as well as the wheelchair/human system provides the information necessary to simulate real-world conditions. [ABSTRACT FROM AUTHOR]

Changing seating posture can extend the amount of time a person can safely remain seated without damaging tissue or becoming fatigued. The Excelsior is an electrically powered wheelchair that utilizes sit-to-stand (STS) and sit-to-recline (STR) motions to aid in pressure relief. The motion of the wheelchair seating system must closely follow anatomical paths or ulcers may develop from the resulting shear forces. Displacement between the person and the wheelchair seating surface is one measure of these shear forces. The displacement between a Hybrid II 50th percentile anthropometric test dummy (ATD) and the seating surface of the Excelsior wheelchair was examined during STS and STR with two cushions, a Jay Active and a low-profile Roho cushion. The difference between the backrest and ATD back angles were 4.29 degrees +/- 2.13 degrees and 1.78 degrees +/- 1.73 degrees for the Roho and Jay cushions respectively during STS and 3.32 degrees +/- 4.21 degrees and 10.71 degrees +/- 6.20 degrees during STR. These were statistically significant at p<.05. During STS, shear displacement between the Hybrid II back and Excelsior backrest did not exceed 1.5 cm for either cushion. ATD thigh-to-seat displacements were 2.5 cm for the Jay and 3.0 cm for the Roho cushion. STR produced dummy thigh-to-seat displacements of 1.5 cm and 3.5 cm for the Jay and Roho cushions respectively. Shear displacement in the ATD back was about 3.5 cm for the Roho and 6 cm for the Jay. The latter displacement should be reduced; however, the other conditions are marginal or acceptable. Hysteresis was acceptable or better for all cushion/motion combinations, with the highest net displacement of about 2.5 cm. [ABSTRACT FROM AUTHOR]

Research is required to advance the understanding of issues related to the effect of physical activity on health and disease prevention among people with disabilities. This report is the result of a consensus process using selected experts in health and exercise. The purpose of the consensus conference was to identify research priorities for physical activity and health among people with disabilities. Priorities were established by 30 participants, who were selected by the principal investigators to achieve balance in the areas of engineering, epidemiology, medicine, nutrition, exercise physiology, and psychology. Experts summarized relevant data from their research and from comprehensive review of the scientific literature on the topic areas chosen for the conference. Public commentary was provided by participants in the 1996 Paralympic Congress. Panel members discussed openly all material presented to them in executive session. Commentary from open discussion periods were recorded and transcribed. Selected panelists prepared first drafts of the consensus statements for each research priority question. All of these drafts were distributed to the panelists and pertinent experts. The documents were edited by the drafting committee to obtain consensus. This research priority setting process revealed that greater emphasis must be placed on determining the risks and benefits of exercise among people with disabilities. Exercise must be studied from the perspective of disease prevention while mitigating risk for injury. Five areas were identified as focal points for future work: epidemiological studies; effects of nutrition on health and ability to exercise; cardiovascular and pulmonary health; children with disabilities; and accessibility and safety of exercise programs. As people with disabilities live longer, the need for addressing long-term health issues and risk for secondary disability must receive greater attention. As a consequence of the consensus process, specific recommendations for future research regarding the impact of exercise on the health and quality of life of persons with disabilities were defined. [ABSTRACT FROM AUTHOR]

Most of the 22 approved or developing ISO standards rely on a wheelchair test dummy, a specialized device described in ISO 7176-11. The purpose of this study was to develop a means for modifying the design of the ISO 7176-11 test dummy to be suitable for testing with higher masses. The changes are based upon published data for obese individuals. With this data, we derived equations for determining the distribution of the additional mass among the test dummy components, and the locations of the centers of mass. The results of this study provide guidelines for adding mass to the 100 kg wheelchair test dummy to accommodate testing of wheelchairs designed for obese individuals. [ABSTRACT FROM AUTHOR]

This technical note illustrates that some of the differences that have been reported regarding wheelchair propulsion may be due to the methods used to calculate key variables. Wheelchair ambulation is a very important form of locomotion that lacks a standard pushrim force and moment analysis system. We have developed tools for analyzing upper limb biomechanics during manual wheelchair propulsion. Among the tools is a system that allows the direct measurement of global coordinate forces Fx, Fy, Fz and corresponding moments. The analytical techniques presented here allow calculation of radial (Fr) and tangential (Ft) forces, the determination of point of force application (PFA), and the moment applied by the hand (Mhz). Our results show that the PFA can be calculated from kinetic data. Comparison of the PFA to the second metacarpophalangeal (MP) joint, calculated from kinematic data and used in previous studies, resulted in a 0.2 radian difference on average, with the PFA showing greater variation near the beginning and ending of the propulsion phase. Analysis of methods for calculating the applied tangential force showed that using the PFA provides a more accurate measurement of this force than the previous method of assuming negligible hand-moment contribution. The hand moment was compared using the calculated PFA and assuming the PFA was coincident with the second MP joint. Both methods provided similar results with a mean difference of 0.6 N.m. The methods presented in this paper provide a framework for analyzing wheelchair propulsion forces and moments. [ABSTRACT FROM AUTHOR]

The goal of this project was to examine the difficulties manual wheelchair users experience in office activities and ascertain whether such problems may be due to poor relationships between the equipment and the users. Sixty adult manual wheelchair users completed a questionnaire about problems encountered in office activities. Filing and writing were the most problematic activities for this group. Phase II of this study consisted of videotaping four subjects performing each activity in their personal office environments, and having them complete a second questionnaire on body-specific locations of discomfort. Videotaped postures and reports of discomfort were matched to determine the existence of poor equipment-user relationships. In filing, low back pain may have been due to bending forward to access lower drawers while seated. For writing, an inappropriate desk-wheelchair relationship that required subjects to bend forward with their arms on a surface that was too high may have caused back, shoulder, and neck discomfort. [ABSTRACT FROM AUTHOR]

The proper selection of a wheelchair requires making several critical decisions, not the least of which is what type of wheelchair is appropriate. The International Organization for Standards (ISO) continues to develop and refine wheelchair standards. Standards allow the objective comparison of products from various sources, permitting consumers or clinicians to assess wheelchairs with which they are not familiar by comparing test results. This study consisted of three components: 1) the comparison of fatigue test results with a planar ANSI/RESNA test dummy to a HERL contoured test dummy; 2) the comparison of fatigue test results for common depot versus common rehabilitation manual wheelchairs; and 3) the comparison of fatigue test results for manual rehabilitation wheelchairs with solid 8-inch casters versus those with pneumatic 8-inch casters. Rehabilitation wheelchairs lasted on average 13.2 times longer than the depot wheelchairs. Both types, tested with the standard ISO-ANSI/RESNA dummy, lasted on average 2.1 times longer than those wheelchairs tested using the contoured dummy. The three rehabilitation wheelchairs equipped with 8-inch pneumatic casters lasted on average 3.2 times longer than the 6 rehabilitation wheelchairs equipped with solid 8-inch casters. The depot wheelchairs cost about 3.4 times as much to operate per cycle or per meter than the rehabilitation wheelchairs. The rehabilitation wheelchairs tended to experience component failures, while the depot wheelchairs tended to experience frame failures. Our testing indicates that the tests in the ISO-ANSI/RESNA standards can relate design features to fatigue test results and durability. Rehabilitation wheelchairs tend to use higher quality materials and better manufacturing practices, and they provide greater mobility for wheelchair users. Purchasers and prescribers of wheelchairs should consider the life-cycle cost and not just the purchase price for wheelchairs. [ABSTRACT FROM AUTHOR]

The range of a power wheelchair depends on many factors including: battery type, battery state, wheelchair/rider weight, terrain, the efficiency of the drive train, and driving behavior. The purpose of this study was to evaluate the feasibility of three methods of estimating power wheelchair range. Another significant purpose was to compare the current draw on pavement to current draw on an International Standards Organization (ISO) Double Drum tester at one m/sec. Tests were performed on seven different power wheelchairs unloaded, and loaded with an ISO 100 kg test dummy. Each chair was configured according to the manufacturer's specifications, and tires were properly inflated. Experienced test technicians were used for the tennis court tests, and treadmill tests. An ISO 100 kg test dummy was used for the ISO Double Drum test. Energy consumption was measured over a distance of 1500 m for each of the three test conditions. The rolling surface was level in all cases. Repeated measure analysis of variance (ANOVA) revealed a significant difference (p = 0.0001) between the predicted range at maximum speed for the three tests. Post hoc analysis demonstrated a significant difference (p<0.01) in estimated range at maximum speed between the Double Drum test and the treadmill test, as well as between the Double Drum test and the tennis court test. Our results indicate no significant difference (p >0.05) between the predicted range at maximal speed between the treadmill and tennis court tests. A simple relationship does not exist between the results of range testing with the Double Drum tester and the tennis court. An alternative would be to permit the use of a treadmill for range testing as simple relationships between all pertinent treadmill and tennis court range data were found. For the Double Drum tester used, the current demand is higher than under normal usage. This presents a problem as current is related to load torque in a power wheelchair. Hence, the Double Drum tester friction must be reduced. The predicted range for the tennis court test at maximum speed ranges from a low of 23.6 km to a high of 57.7 km. The range of the power wheelchair can be improved by the use of wet lead acid batteries in place of gel lead acid batteries. [ABSTRACT FROM AUTHOR]

Rehabilitation goals following major combat-associated limb loss in World War II and the Vietnam war focused on treatment of the injury and a return to civilian life. The goal for Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) servicemembers is to restore function to the greatest possible degree and, if they desire, return them to Active Duty, by providing them with extensive rehabilitation services and a variety of prosthetic devices. Our study determines the usefulness of these diverse types of prosthetic devices for restoring functional capability and documents prosthesis use and satisfaction. We compare servicemembers and veterans with major combat-associated unilateral lower-limb loss: 178 from the Vietnam war and 172 from OIF/OEF conflicts. Of survey participants with unilateral lower-limb loss, 84% of the Vietnam group and 94% of the OIF/OEF group currently use at least one prosthetic device. Reasons for rejection varied by type of device, but common reasons were pain, prosthesis too heavy, and poor fit. Abandonment is infrequent (11% Vietnam group, 4% OIF/OEF group). Future efforts should aim to improve prosthetic-device design, decrease pain, and improve quality of life for these veterans and servicemembers. [ABSTRACT FROM AUTHOR]

The Guido is a robotic walker that provides navigation and obstacle-avoidance assistance. Engineering tests have found that the device performs adequately and presents no hazard to the user. The performance of the Guido was compared with a low-tech mobility aid, the Assistive Mobility Device (AMD) developed at the Atlanta Department of Veterans Affairs Medical Center, in trials involving older adults with visual impairments. The purpose of this study was to determine whether the Guido could increase the safety and mobility of elderly visually impaired individuals in supervised care facilities. Subjects traversed an obstacle course with the Guido and the AMD. Completion time, obstacle/wall contacts, and reorientations were compared for both devices. No significant differences were found between the devices for any of the tests. The Guido did not perform better than the AMD during the trials. Revisions to the device as well as a change in subject requirements and testing protocol may produce different results. [ABSTRACT FROM AUTHOR]

This study examined the usage of powered seating functions, including tilt-in-space, backrest recline, and seat elevation, among a group of wheelchair users during their typical daily activities. Twelve individuals who used a power wheelchair with seating functions participated in the study. They drove their own wheelchair and used the seating functions as needed in their community environment for about 2 weeks while the seating function usage was recorded with a portable device. We found that subjects occupied their wheelchair for 11.8 +/DS 3.4 hours a day (all data shown as mean +/DS standard deviation). While occupying their wheelchairs, they accessed tilt-in-space, backrest recline, and seat elevation 19 +/DS 14 times a day for 64.1% +/DS 36.8%, 12 +/DS 8 times for 76.0% +/DS 29.8%, and 4 +/DS 4 times for 22.5% +/DS 34.9%, respectively. Subjects chose to stay in tilted and reclined positions in their wheelchair for 39.3% +/DS 36.5% of their time each day. They spent little time in a fully upright position. Subjects changed their seating positions every 53.6 +/DS 47.0 minutes. Time spent in positions of different seating pressures varied among subjects. The information collected could enhance clinical practice of wheelchair provision, resulting in better compliance with clinical instructions and appropriate use of seating functions among wheelchair users. [ABSTRACT FROM AUTHOR]

Inthis pilot study, we assessed wheelchair durability and its effect on user satisfaction. Specifically, we examined the characteristics of the participants' wheelchairs, the types of maintenance and repairs completed, and whether the participants' satisfaction was affected by problems with their wheelchairs. A convenience sample of 130 participants who used wheelchairs as their primary means of mobility was recruited. Participants completed a questionnaire about their wheelchairs, the maintenance and repair history, and their satisfaction levels. Results showed that 26% of the participants had completed a wheelchair repair in the past 6 months, 16% had completed general maintenance, and 27% had completed tire repairs. Neither hours of wheelchair use nor wheelchair age affected repair or maintenance frequency. Participants were generally satisfied with their wheelchairs. Better understanding of wheelchair maintenance and repair issues will guide improvements in wheelchair design and enhance the community participation of individuals who use wheelchairs. [ABSTRACT FROM AUTHOR]

For individuals with a spinal cord injury or dysfunction (SCI/D), opportunities to exercise are limited and are usually not highly motivating experiences. Exercise programs or extracurricular activities may help increase or maintain the cardiovascular fitness level of individuals with SCI/D. The GAMEWheels system, an interface between a portable roller system and a computer, enables an individual to control a video game by propelling his or her wheelchair. The purpose of this study was to investigate whether the propulsive forces used during video play, both with and without the GAMEWheels system, were different. A secondary purpose was to examine differences in metabolic parameters during exercise under these two conditions. Ten manual wheelchair users exercised on the GAMEWheels system with and without controlling a video game. Physiological and kinetic data were collected six times during two exercise trials. Kinetic data were recorded with the SMARTWheel and used to investigate propulsion forces. No significant differences were found in the resultant force, rate of rise, or number of hand contacts with the pushrims. This study showed that propulsion pattern did not change significantly when wheelchair users exercised while playing a computer video game. Oxygen consumption, ventilation, and heart rate were significantly different (p < 0.05) between the two groups during the last three exercise intervals and cooldown. Playing a video game while exercising may help to motivate manual wheelchair users to exercise longer and regularly, something that was reported by this study's subjects; likewise, exercising while playing a video game may not be associated with higher pushrim forces and stroke frequencies. [ABSTRACT FROM AUTHOR]

Shoulder pain and rotator cuff tears are highly prevalent in individuals with paraplegia (PP). The purpose of this study was to use magnetic resonance imaging (MRI), plain radiographs, questionnaires, and physical examination to gain insight into the prevalence of shoulder disorders in individuals with PP. A total of 28 individuals with PP was recruited (mean age=35; mean year from injury=11.5). Each subject completed a questionnaire designed to identify arm pain, had a standard physical examination focusing on the shoulder, and underwent imaging studies (radiographic and MRI). Nine of the thirty-two subjects (36 percent) experienced shoulder pain in the month prior to testing. The MRI studies documented only one rotator cuff tear. Five subjects showed osteolysis of the distal clavicle by plain radiographic study. In two subjects this was seen bilaterally. Although no relationship was seen between pain and imaging abnormalities, stepwise linear regressions found a statistically significant positive relationship between imaging abnormalities and body mass index (BMI) (radiographic: beta= 0.56, p<0.01; MRI: beta=0.52, p<0.01). This study found a low prevalence of rotator cuff tears and a high prevalence of distal clavicle osteolysis in a sample of relatively young individuals with PP. Although there was only one tear identified by MRI, a number of subclinical abnormalities were seen and found to correlate with BMI. [ABSTRACT FROM AUTHOR]

Wheelchair designs based upon loads applied quasi-statically during normal mobility use are likely inadequate to handle the increased level of dynamic crash forces that may be encountered when using the wheelchair as a motor vehicle seat. The purpose of this study was to characterize the integrity of wheelchair caster assemblies under simulated crash conditions. This study utilized dynamic drop (DD) testing, with loading levels and rates adjusted to match those found previously in sled impact testing and computer crash simulations. The results verify that current caster assembly designs may not be able to withstand forces associated with a crash. Five of seven evaluated caster assemblies failed when loaded to 8,007 N, or less, at loading rates seen in sled testing. DD testing used in this study is a valuable tool that can be used in the design of transport wheelchair components. [ABSTRACT FROM AUTHOR]

Returning wounded veterans and servicemembers to their highest level of function following traumatic injury is a priority of the Departments of Defense and Veterans Affairs. We surveyed 245 veterans from the Vietnam war and 226 servicemembers and veterans from Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) conflicts with at least one major traumatic lower-limb loss to determine their use of mobility assistive technology (AT) and patterns of limb abandonment. Prosthetic device use without wheelchair use is found in 50.5% of Vietnam and 42.8% of OIF/OEF groups. Prostheses and supplementary wheelchairs are used by Vietnam (32%) and OIF/OEF (53%) groups (p < 0.01). Exclusive wheelchair use is more frequent in the Vietnam group (18%) than in the OIF/OEF group (4.0%, p < 0.01). In Vietnam participants, multivariate analysis found that multiple-limb loss (adjusted odds ratio [AOR] = 14.5; 95% confidence interval [CI] 5.5-38.5), bilateral lower-limb loss (AOR = 12.7; 95% CI 6.2-26.1), and number of comorbidities (AOR = 1.3; 95% CI 1.2-1.5) are associated with increased likelihood of wheelchair use. In OIF/OEF participants, bilateral lower-limb loss (AOR = 29.8; 95% CI 11.0-80.7), multiple-limb loss (AOR = 16.3; 95% CI 3.1-85.3), cumulative trauma disorder (AOR = 2.4; 95% CI 1.2-4.9), and number of combat injuries (AOR = 1.4; 95% CI 1.2-1.7) are associated with wheelchair use. Combined use of different types of mobility ATs promotes improved rehabilitation and ability to function. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) causes a wide variety of neurological deficits, with ambulatory impairment the most obvious cause of disability. Within 10 to 15 years of disease onset, 80% of persons with MS experience gait problems due to muscle weakness or spasticity, fatigue, and loss of balance. To facilitate mobility, persons with MS frequently use mobility assistive technology (MAT), such as canes, crutches, walkers, wheelchairs, and scooters. We systematically reviewed the published literature on MAT use among persons with MS. We used electronic reference lists such as Ovid MEDLINE and PubMed to search the literature. We located 50 articles that met the initial criteria of providing good evidence of the types of MAT devices and their benefits for individuals with MS. A limited number of articles with higher levels of evidence was found regarding benefits of MAT use specifically for persons with MS. Evidence-based literature provides the basis for the strongest method of measurable clinical performance; therefore, having a strong research study design is vital to the justification of MAT prescription and reimbursement decisions. However, a paucity of studies with higher levels of evidence-based practice exists. [ABSTRACT FROM AUTHOR]

People with disabilities such as multiple sclerosis and Parkinson's disease have difficulty operating conventional movement-sensing joysticks (MSJs) because of varying levels of tremor. We developed an isometric joystick (IJ) that has performed as well as a conventional MSJ when used by persons with upper-limb impairments in real and virtual wheelchair driving tasks. The Weighted-Frequency Fourier Linear Combiner (WFLC) filter has been used to cancel tremor effectively in microsurgery. In this study, we compared an MSJ, IJ, and IJ with the WFLC filter in individuals performing a virtual driving task. Although the WFLC filter did not improve driving performance in this study, the IJ without a filter yielded better results than the conventional MSJ and thus may be a potential alternative to the MSJ in minimizing the effects of tremor. [ABSTRACT FROM AUTHOR]

A group of 158 service members who sustained major limb amputations during the global war on terrorism were surveyed on their satisfaction with the quality of care received from the Walter Reed Army Medical Center (WRAMC) Amputee Clinic from the time of their injury to their inpatient discharge. Of these participants, 96% were male, 77% were Caucasian, 89% were enlisted personnel, and 68% had sustained lower-limb amputations. WRAMC inpatient therapy, peer visitors, overall medical care, and pain management received particularly high satisfaction ratings. Age, race, rank, and level and side of amputation had little effect on overall satisfaction ratings. Significant differences, however, were found by location of injury (Iraq vs Afghanistan, Cuba, and Africa) regarding satisfaction with care received while in Europe and with the education process at WRAMC. Study findings strongly support the rehabilitation-based, integrative care approach designed by the U.S. military to care for service members with amputations. [ABSTRACT FROM AUTHOR]

Individuals with multiple sclerosis (MS) report decreased satisfaction with their mobility devices compared with individuals with spinal cord injuries (SCIs). This study (1) investigated the demographic differences between veterans with MS (V-MS) and veterans with SCI (V-SCI) who were issued a wheelchair by the Veterans Health Administration (VHA) and (2) described differences in mobility device prescription. We merged two VHA databases to obtain demographic and wheelchair information for all V-MS and V-SCI in 2000 and 2001. Descriptive information for issued wheelchairs was available for 2,154 V-MS and V-SCI. We found that V-MS were significantly less likely to receive higher quality wheelchairs (manual or power) compared with V-SCI (p < 0.001). The disparity in VHA wheelchair prescription between these two groups indicates a need for further research regarding the assistive device prescription process in these populations. [ABSTRACT FROM AUTHOR]

Little is known about the reasoning process clinicians use when prescribing wheeled mobility equipment (WME) or about the outcomes of this process, i.e., how many devices are prescribed, to whom, how often, and at what cost. This study characterized veterans who received WME from the Veterans Health Administration. We analyzed variance in wheelchair provision based on sex, race/ethnicity, diagnosis, and age. Three years of data from the National Prosthetics Patient Database and the National Patient Care Database were merged, yielding more than 77,000 observations per fiscal year. Logistic regression analysis revealed associations between WME provision and age, sex, and race/ethnicity, when analysis was controlled for diagnosis and number of comorbidities. Hispanics (odds ratio [OR] = 1.864), African Americans (OR = 1.360), and American Indians/Asians (OR = 1.585) were more likely than Caucasians to receive standard wheelchairs. Hispanics (OR = 0.4), African Americans (OR = 0.7), and American Indians/Asians (OR = 0.4) were less likely than Caucasians to receive scooters. [ABSTRACT FROM AUTHOR]

Over 50 percent of manual wheelchair users with spinal cord injury (SCI) are likely to develop upper-limb pain and injury. The majority of studies related to pain have implicated wheelchair propulsion as a cause. This paper draws from a large multisite trial and a long-standing research program to make specific recommendations related to wheelchair propulsion that may decrease the risk of upper-limb injury. The studies include over 60 subjects over 1 yr after a traumatic SCI below the second thoracic level. Specific aspects of the propulsive stroke that may relate to injury include cadence, magnitude of force, and the pattern of the hand during the nonpropulsive part of the stroke. Lower peak forces, slower cadence, and a circular propulsive stroke in which the hand falls below the pushrim during recovery may help prevent injury. In addition, wheelchair users should use the lightest weight adjustable wheelchair possible. Future work should include interventional trials and larger studies that allow for more complex statistical models that can further detail the relationship between wheelchair propulsion, user characteristics, and upper-limb injuries. [ABSTRACT FROM AUTHOR]

Rehabilitation scientists and biomedical engineers have been investigating wheelchair propulsion biomechanics in order to prevent musculoskeletal injuries. Several studies have investigated wheelchair propulsion biomechanics; however, few have examined wheelchair propulsion stroke patterns. The purpose of this study was to characterize wheelchair propulsion stroke patterns by investigating joint accelerations, joint range of motions, wheelchair propulsion phases, and stroke efficiency. Seven experienced wheelchair users (5 males, 2 females) were filmed using a three-camera motion analysis system. Each subject pushed a standard wheelchair fitted with a force-sensing pushrim (SMARTWheel) at two speeds (1.3 and 2.2 m/s). The elbow angle was analyzed in the sagittal plane, while the shoulder joint was analyzed in the sagittal and frontal planes. Three distinctly different stroke patterns: semi-circular (SC), single looping-over-propulsion (SLOP), and double looping-over-propulsion (DLOP), were identified from the kinematic analysis. Through our analysis of these patterns, we hypothesized that SC was more biomechanically efficient than the other stroke patterns. Future studies using a larger number of subjects and strokes may reveal more significant distinctions in efficiency measures between stroke patterns. [ABSTRACT FROM AUTHOR]