Feedback improves compliance of pressure relief activities in wheelchair users with spinal cord injury

STUDY DESIGN Prospective cross-sectional pre-post pilot study. OBJECTIVES This pilot study aimed to evaluate the potential for improving pressure relief behaviour in wheelchair users with spinal cord injury (SCI) using a novel feedback system based on textile pressure sensor technology. SETTING In- and out-patient clinic of the Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland. METHODS Nine wheelchair users with SCI (3 females, 50 ± 12 years of age, 2 tetra- and 7 paraplegics) were equipped with a feedback system (sensomative$_{wheelchair}$) for three continuous weeks. The system consists of a textile pressure mat and a mobile smartphone application that reminds participants to perform missing pressure reliefs during regular and unobserved wheelchair usage in a customized manner. Pressure reliefs were detected using a subject-specific random forest classifier. Improvements of relief quality, duration and frequency were analysed by comparing week 1 (baseline) with no feedback, i.e., only pressure data recorded, against week 2 (with feedback). Carry-over effects of improved relief behaviour were studied in week 3 (no feedback, pressure data only recorded). RESULTS All participants increased their relief frequency and performed in median 82% (IQRs: 55%-99%) of the required reliefs while using the feedback system, whereas the median relief frequency was only 11% (IQRs: 10%-31%) during the baseline condition. Every participant who did not perform reliefs of sufficient duration (based on the recommendations of the therapist) during week 1 showed a significant improvement while using the feedback system. CONCLUSION Subject-specific feedback using the novel feedback system may have the potential for improving the regularity of an individual's relief activities, and may ultimately be an instrument for reducing the risk of developing pressure ulcers