Ortho-Monitorizer: A portable device for quantitative monitoring of temperature and pressure in a 3D-printed upper limb orthosis.

Abstract

Background: Adherence to wrist-hand orthoses in patients with musculoskeletal conditions, such as Carpal Tunnel Syndrome, is crucial for effective rehabilitation. However, objective methods for monitoring wear time and pressure distribution remain limited.

Purpose: This study presents the Ortho-Monitorizer, a portable 3D-printed sensor-integrated device designed to provide real-time, quantitative monitoring of temperature and pressure in upper limb orthoses. The objective is to evaluate the system's feasibility in detecting patient adherence and identifying critical pressure points.

Study design: A descriptive and cross-sectional study was conducted to develop and validate the device, including sensor integration and data acquisition.

Methods: Using a 3D scanner and Fusion 360 software, the orthoses were customized and printed in thermoplastic polyurethane. Data from healthy participants (n = 55) and patients with Carpal Tunnel Syndrome (n = 2) were collected through the Ortho-Monitorizer's application, using six sensors (three temperature and three pressure sensors) placed at clinically relevant anatomical points. Data were acquired over five hand positions, and normal reference values were established.

Results: Mean temperature values ranged between 29.5^∘C and 32.5^∘C, while pressure values varied from 0.00 MPa to 0.08 MPa across different hand positions. One CTS patient exhibited pressure values above normal thresholds in specific positions, correlating with discomfort and numbness reports. The device achieved a System Usability Scale (SUS) score of 86.8% (healthy participants) and 92.5% (CTS patients), indicating high usability and acceptance.

Conclusions: The Ortho-Monitorizer provides a non-invasive, objective method for monitoring patient adherence to orthotic treatments. By offering real-time tracking of critical parameters, it enhances clinical decision-making and patient outcomes. Future research should explore wireless integration and long-term clinical validation to further optimize its applicability.