Measurement of Hand Function by an Automated Device-System Validation and Usability Analysis

(1) Aim: This study aims to assess the repeatability and accuracy of a 9-axis IMU-based glove and an IR camera system, in order to determine their potential to replace traditional goniometry. (2) Background: Traditional methods for assessing hand function, such as goniometry, are time-consuming and limited by subjectivity, inter-rater variability and external factors that compromise accuracy and reliability. Recent advancements in motion capture technology and sensor-based devices offer potential improvements in efficiency and accuracy for hand rehabilitation assessment; (3) Methods: To evaluate the repeatability of an IMU-based glove and an IR camera, measurements were taken using a silicone hand model under controlled conditions, while accuracy assessments involved a volunteer without movement constraints. Bland-Altman plots were employed for visual comparison and accuracy evaluation; (4) Results: The Nuada glove exhibited high repeatability, with standard deviations below two degrees across all joints, surpassing the goniometer's accuracy threshold of five degrees. The UltraLeap system demonstrated comparable repeatability, with deviations consistently under 3.5 degrees. Accuracy assessments revealed limitations: over 50% of the Nuada glove's measurements and over 80% of UltraLeap's measurements deviated by more than five degrees compared to the goniometer. However, the Nuada glove and UltraLeap system were more consistent with each other than with the goniometer, suggesting limitations in the goniometer's reliability for modern mobility assessment; (5) Conclusions: Both devices exhibited excellent repeatability, highlighting their strong potential for clinical application. However, their accuracy compared to the goniometer requires further refinement. These findings suggest that these technologies could enhance traditional assessment methods, offering more efficient and accurate solutions for evaluating hand mobility in clinical settings.