Clinical Validation and Outcome Measures From Bend Ease: A Novel, Sensor-Based Digital Measurement Tool for Assessing At-Home Morning Stiffness and Spinal Range of Motion in Axial Spondyloarthritis.
Publication Title
Rheumatol Ther
Document Type
Article
Publication Date
4-1-2025
Keywords
washington; swedish
Abstract
INTRODUCTION: To evaluate the accuracy, reliability, and usability of Bend Ease, a novel smartphone-based digital health technology (DHT), which objectively self-measures spinal range of motion (SRoM) and remotely assesses morning stiffness.
METHODS: This phase 1 study involved healthy volunteers (HV) and patients with axial spondyloarthritis (axSpA). Participants used Bend Ease by placing a phone against their chest during a forward-flexion bend, and the application collected and processed accelerometry data to measure bend angle in both clinical and at-home settings. Bend Ease measurements were compared to the video-based method (gold standard) and functional ability questionnaires.
RESULTS: The study included 30 HV and 30 patients with axSpA. Bend Ease accurately measured forward-flexion bend angles, demonstrating strong correlation (r = 0.74) and concordance (ρ
CONCLUSIONS: Bend Ease is an accurate, reliable, and user-friendly tool for assessing SRoM. As the first DHT to objectively evaluate morning stiffness upon waking, Bend Ease provides valuable assessments of spinal mobility when it is most impaired.
Area of Special Interest
Neurosciences (Brain & Spine)
Area of Special Interest
Orthopedics & Sports Medicine
Specialty/Research Institute
Rheumatology
Specialty/Research Institute
Orthopedics
DOI
10.1007/s40744-025-00746-w
