Evaluating the Functionality and Usability of Two Novel Wheelchair Anti-Rollback Devices for Ramp Ascent in Manual Wheelchair Users With Spinal Cord Injury

Background: Difficulty ascending ramps and inclines with a manual wheelchair adversely affects the everyday mobility and overall quality of life of manual wheelchair users. Currently, various anti-rollback devices are available to assist manual wheelchair users to ascend ramps and inclines. However, these devices have 2 main shortcomings: restriction to backward motion limiting recovery from an overturning wheelchair, which is a safety concern; and difficulty in engaging/disengaging the device while on the ramp. Objective: To evaluate the functionality and usability of 2 novel wheelchair anti-rollback devices developed to address these shortcomings (prototypes Wheel and Brake). Design: Cross-sectional. Setting: Rehabilitation research facility. Participants: Twelve adult participants with chronic spinal cord injury. Methods: Participants completed training and tested with both the wheelchair anti-rollback devices on a 7.3-m-long ramp. Main Outcome Measurements: Number of stops, perceived physical exertion, pain, and ease of use of these devices as participants maneuvered their wheelchairs up a 7.3-m ramp were assessed. Participants also evaluated their satisfaction with the usability of both the devices using the Quebec User Evaluation of Satisfaction With Assistive Technology (QUEST 2.0). Results: Both prototypes evaluated overcame the limitations of the existing anti-rollback devices. Nonparametric statistical tests showed that participants rated both prototypes similarly for the overall functional and usability aspects. However, the participants' satisfactory rating were higher for the prototype Brake than for the prototype Wheel based on a functional aspect (ie, engaging/disengaging easiness), and higher for Wheel than for Brake, based on a usability aspect (prototype size). Conclusions: The qualitative and quantitative outcomes of this investigation, based on the usability and functional evaluations, provided useful information for the improvement in the design of both anti-rollback devices, which may allow manual wheelchair users to manage ramp ascent more safely and easily. Further evaluations with a different SCI population is recommended.