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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]

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]

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]

Objective: Adolescents with acquired brain injuries are at risk for additional injuries after hospital discharge. We asked healthcare providers to identify and prioritise urgent hazards in the home setting for this population., Methods: We used a convergent mixed methods approach. Healthcare providers who do discharge planning and community re-integration for adolescent patients with brain injury were recruited from hospitals in the US Midwest. Participants completed two structured surveys, semi-structured interviews and a Hazard Prioritisation Matrix Activity. We analysed quantitative data via descriptive statistics and qualitative data via inductive thematic analysis to identify hazards, urgency, interactive themes and generate a conceptual model., Results: All participants validated four preidentified hazards in the surveys and the interviews: slippery objects on the floor, large furniture/objects in the path of travel, unattended open flames and inappropriate use of cooking appliances. 59 hazards were self-identified during the Hazard Priority Matrix Activity and assigned an urgency rating, with 12 (20.3%) urgent, 20 (33.9%) major, 19 (32.2%) moderate and 8 (13.6%) minor risks. We identified seven interactive themes about hazard factors: hazardous activities, hazardous situations, hazardous objects, hazardous others, hazardous spaces, harms and client factors. A conceptual model for home safety concerns links hazards, risks and harms., Conclusions: Adolescents with acquired brain injuries need healthcare providers to recognise unique and complex hazards in their homes that could lead to harm. Mitigating home hazards may prevent additional unintentional injury for these adolescents. More research is needed to generalise this information for this population across clinical settings., Trial Registration Number: NCT04768946., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Individuals with cognitive disabilities have challenges with personal navigation and wayfinding, especially when traveling on public transportation. The purpose of this case study is to describe the structure and implementation of the Personal Navigation for Individuals with Disabilities (PNID) education and training program, which is based on a socio-technical architecture for individuals with cognitive disabilities within a fixed-route public bus system. A case study methodology was used to describe preliminary findings of the skills, attributes, and experiences of three individuals with cognitive disabilities as it relates to transportation on fixed-route bus systems in a midsized urban setting. The three individuals completed five training activities: safety, public bus, smartphone, WayFinder App, and fixed-route bus system. The case study provided a preliminary mixed-methods overview of training travelers with cognitive disabilities to use the WayFinder system while accessing fixed-route public bus system. The insights and strategies identified through the case study demonstrate the potential opportunities for development, implementation, and sustainability of the PNID program in other midsized urban settings. The PNID program (i.e. AT service delivery process), in combination with the WayFinder system (i.e. assistive technology), has the potential to meet the unique needs of individuals with cognitive disabilities when accessing public transportation.

Objective: The purpose of this paper is to describe non-participation during the outcome measurement step of the wheeled mobility service delivery process (WMSDP) based on the Functional Mobility Assessment (FMA)-Uniform Dataset (UDS) Registry., Introduction: The WMSDP is a standard framework for the provision of wheeled mobility devices, and several factors influence the client's experience throughout the process. Patient-reported outcomes are one way to measure the client's experience as part of a quality improvement program., Methods: A retrospective descriptive study was conducted on the FMA-UDS Registry to measure the response rate during the outcome measurement step of the WMSDP and describe the reasons an individual did not complete the FMA-UDS. The FMA-UDS was examined at two time points: pre-delivery and post-delivery of the wheeled mobility device., Results: As of September 2, 2021, 10,253 cases have been entered into the FMA-UDS Registry. 2,247 cases were no longer participating pre-delivery, and an additional 3,905 cases were no longer participating post-delivery. The most common reasons for non-participation in the FMA-UDS pre-delivery and post-delivery included: equipment not delivered; provider no longer participating in the FMA-UDS; funding issues; no new equipment; client opted out; loss in contact; deceased; returned equipment; and other., Discussion: The type and frequency of non-participation in the outcome measurement step of the WMSDP is critical to understanding why individuals participate in outcome measures and provides insight into the barriers and facilitators for the implementation of quality improvement programs.

The rehabilitation engineering professions include rehabilitation engineers, rehabilitation technologists / assistive technologists and rehabilitation technicians. The purpose of this white paper is to define the rehabilitation engineering professions, describe educational pathways for the field of rehabilitation engineering, and describe the role of the rehabilitation engineering professions in a multitude of professional settings. An ad-hoc committee was convened by the Rehabilitation Engineering and Technologists (RE&T) Professional Standards Group (PSG) at the 2013 annual meeting, RESNA Conference in Seattle, Washington. The ad-hoc committee reviewed over 80 different sources in preparing the white paper, which included peer reviewed journal articles, conference proceedings, professional organization websites. Based on this review, in addition to expert opinion and stakeholder feedback, the committee developed the following definitions. Rehabilitation Engineer (RE) uses the innovative and methodical application of scientific knowledge and technology to design and develop a device, system or process, which is intended to satisfy the human needs of an individual with a disability. Rehabilitation Technologist / Assistive Technologist (RT/AT) combines scientific and engineering knowledge and methods with technical skills to complement engineering activities for an individual with a disability. Rehabilitation Technician (RTn) works with equipment, primarily assembling and testing component parts of devices or systems that have been designed by others for individuals with disabilities; usually under direct supervision of a rehabilitation engineer or rehabilitation technologist / assistive technologist. Their preferences are given to assembly, repair, or evolutionary improvements to technical equipment by learning its characteristics, rather than by studying the scientific or engineering basis for its original design.This whitepaper provides a framework for future discussions on the advancement of the rehabilitation engineering professions with the goal of improving the quality of life of individuals with disabilities through the application of science and technology.

Purpose: Complex rehabilitation technologies (CRT) support independence for individuals with disabilities by enabling mobility for function, employment, education, and independent living. CRT service delivery is evolving, with changes to funding, provider qualifications, consumer needs, and technological advances. This scoping review investigated service delivery processes for individuals with disabilities who have a mobility impairment, while specifically identifying best practices, barriers, and unique features of health delivery policies and practices., Methods: We used a framework described by Colquhoun et. al. for conducting scoping reviews, a six-step process that includes: 1) identifying the research question, 2) identifying studies, 3) selecting studies 4) data charting, 5) reporting results and 6) consultation. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) was also used for reporting results of the review., Results: Common categories were identified and organised into a hierarchical structure of four categories and 16 sub-categories. The primary categories included "policy", "consumer", "service delivery", and "wheeled mobility devices". The sub-categories described funding sources, consumer and professional populations, service delivery guidelines, and types of mobility devices. Analysis indicated the data were from 21 countries and 14 combinations of funding sources, and the articles were primarily descriptive studies., Conclusion: This scoping review identified evidence from various countries, health systems, and stakeholder. Currently, this process does not proactively address the needs of individuals with mobility disabilities. The scoping review provides the foundation for the development of a novel policy on the provision of CRT services and devices to address these needs.Implications for RehabilitationExamination of national and international service delivery practices in diverse clinical and funding environments indicate various challenges and opportunities for improvement.CRT consumers are negatively impacted by current service delivery practices, including long wait times, lack of specialised clinical expertise, and limited consumer education opportunities.More consistent and widespread research is needed within the CRT provision industry to grow evidence-based practice related to complex rehabilitation technology and individuals with disabilities.

Objective: The aims of the study were to report the demographic characteristics and functional mobility for individuals accessing an academic medical center mobility device clinic and to compare functional mobility data across demographic characteristics and mobility device type., Design: This study used a retrospective, cross-sectional design. Demographic, mobility type, and patient-reported outcome measure data for 833 clients were analyzed. The Functional Mobility Assessment was used as the patient-reported outcome measure to determine satisfaction., Results: The mean (SD) baseline Functional Mobility Assessment score was 0.59 (0.25) on a 0-1 scale. Significant differences with the Functional Mobility Assessment scores were found across the mobility device types, with scooter and power wheelchair groups reporting higher satisfaction scores than those in the cane/crutch/walker or manual wheelchair groups. Device type, sex, and age were each found to be significant predictors of satisfaction scores (P < 0.01)., Conclusions: Mobility device type is associated with satisfaction level. Mobility devices that offer higher levels of assistance are associated with increased satisfaction. The Functional Mobility Assessment, mobility device type, and demographic data provide baseline information for evaluating the effectiveness of an academic medical center mobility device clinic.

Although wheelchair users are frequently subjected to oscillatory and shock vibrations, little research has been conducted to assess the whole-body vibration exposure of wheelchair users. The purpose of this study was to determine if selected wheelchair cushions alter potentially harmful whole-body vibrations transferred to wheelchair users. Thirty-two participants, who use wheelchairs as their primary mode of mobility, contributed to this study. Four of the most commonly prescribed wheelchair cushions were selected. Participants were asked to propel their wheelchair over a simulated activities of daily living (ADL) course while acceleration and force data were recorded. A repeated measures ANOVA showed no significant differences between the different cushions for the total averaged absorbed power (p = 0.190), the 50 mm curb drop (p = 0.234), or the rumble strip (p = 0.143). A repeated measure ANOVA for the peak curb drop absorbed power revealed a significant difference in the cushions (p = 0.043). The cushions that were most effective in this testing appear to be the Invacare Pindot and the Varilite Solo. Not only did those cushions appear to have the lowest values much of the time but also they did not display the highest values. When comparing results from a similar study, absorbed power appears to be as effective in determining vibration effects in the time domain as the methods in the ISO 2631 Standard.

Although the exposure to whole-body vibrations (WBV) has been shown to be detrimental to seated humans, the effects of wheelchairs and seating systems on the transmission of vibration to an individual have not been thoroughly examined. The purpose of this study was to determine if the selected wheelchair seat cushions and back supports minimize the transmission of vibrations. Thirty-two wheelchair users traversed an activities of daily living course three times using 16 randomly selected seating systems as well as their own. Vibrations were measured using triaxial accelerometers at the seat and participant's head. The weighted fore-to-aft (Tx), vertical (Tz), and resultant (Tr) transmissibility based on the vibrational-dose-value (VDV) were used to determine if differences existed among the four seat cushions and back supports. The obstacles that seem to have the largest effect on the transmission of WBV are the single event shocks and the repeated event shocks. Comparisons between the individuals own seating system and the tested seating systems suggest that the individuals are not using the most appropriate seating system in terms of the reduction of vibration transmission.

The purpose of this study was to describe the frequency content of racing wheelchair propulsion motion data. The selection of the filter corner frequency in previous kinematic analyses of manual wheelchair propulsion was commonly based on gait literature. An estimate of the frequency separating the signal and the noise was determined to make recommendations for low-pass digital filters. The global (noncoordinate specific) cutoff frequency was 6 Hz. The directional cutoff frequencies were 5.1, 3.9, and 5.6 Hz, in the anterior-posterior, superior-inferior and medial-lateral directions, respectively. Recommendations for the corner frequencies of low-pass Butterworth digital filters based on the cutoff frequency are higher than the corner frequencies used in previous studies of manual wheelchair propulsion kinematic data. This study provides a foundation for the data reduction of manual wheelchair propulsion kinematic data that is independent of gait literature.

Objective: To compare the durability of two designs of cross-braces for folding manual wheelchairs and to determine the nature of wheelchair cross-brace failures., Design: Fatigue testing of two folding wheelchair cross-brace designs (one with a rectangular cross-section and the other with a circular cross-section). A total of 20 cross-brace pairs were tested., Results: The cross-braces with a circular cross-section endured a mean +/- SD of 100,159 +/- 45,814 cycles before experiencing a fatigue failure, whereas the cross-braces with a rectangular cross-section endured an average of 261,254 +/- 160,741 cycles. A t test showed significant differences (p = .01) in fatigue-life between cross-braces with a circular cross-section versus cross-braces with a rectangular cross-section. All 20 cross-braces experienced similar fatigue failures that would develop at the bolt hole where the two cross-braces connect to form a hinge., Conclusion: The results suggest that the rectangular cross-brace design has a longer fatigue-life than the circular cross-brace design. People should regularly inspect the cross-brace for cracks. The area around the bolt forming the hinge should be inspected carefully. If a crack is observed, the cross-brace should be replaced immediately.