Telehealth monitor to measure physical activity and pressure relief maneuver performance in wheelchair users

ABSTRACT

This study demonstrated the feasibility of a device for monitoring pressure relief maneuvers and physical activity for wheelchair users. The device counts the number of wheel pushes based on wheelchair acceleration and measures pressure relief maneuvers using a seat sensor consisting of three force sensing resistors (FSRs). To establish the feasibility of the seat sensor for the detection of pressure relief maneuvers, 10 wheelchair users and 10 non-disabled controls completed a series of wheelchair depression raises, forward trunk leans, and lateral trunk leans. The seat sensor was placed underneath the user’s seat cushion. To establish the feasibility of wheel push counting, 10 full-time wheelchair users navigated a flat 50-m outdoor track and a 100-m outdoor obstacle course during self-propulsion (e.g., wheel pushes) and during assisted-propulsion (e.g., no wheel pushes). Of the 240 performed pressure relief, 225 were properly classified by the seat sensor (accuracy: 94%, sensitivity: 96%, specificity: 80%). Sensitivity was highest for depression raises (98%) and lowest for front lean maneuvers (80%). The wheelchair activity monitor measured 2,112 pushes during the self-propulsion trials compared to 2,162 pushes measured with the instrumented push-rim (97.7%). During assisted-propulsion trials, there were 477 incorrectly identified pushes (8.0 per trial).

KEYWORDS:

• accelerometer
• activity monitor
• pressure relief
• wheelchair

Acknowledgments

The authors gratefully acknowledge the work of Ms. Ariane Calendar, Mr. Yuan Hui Cao, Dr. Bor-rong Chen, Mr. Robert Gonsiewski, Mr. Daniel Kendrix, and Mr. Junyu Zhu who contributed to the development of the device tested in this study.

Funding

This work was supported by a grant from the National Center for Medical Rehabilitation Research at the National Institute for Child Health and Human Development (1R43HD076524) and a grant from the National Institute on Disability and Rehabilitation Research (H133N110018).

Additional information

Funding

This work was supported by a grant from the National Center for Medical Rehabilitation Research at the National Institute for Child Health and Human Development (1R43HD076524) and a grant from the National Institute on Disability and Rehabilitation Research (H133N110018).