The aim of this graduation project was to develop an ergonomic support tool to prevent work-related musculoskeletal disorders (WRMDs) among sonographers, particularly shoulder strain during ultrasound procedures. The project began with an examination of the clinical context, ergonomic challenges and physical demands of sonographic work. Through observations, interviews and electromyography (EMG) testing, key factors were identified, including prolonged shoulder abduction and high muscle activity, particularly in the supraspinatus.

This research resulted in the development of Lofius, a supporting device designed to reduce shoulder load while allowing full range of motion. The tool was adapted for use in the departments of paediatrics and gynaecology, to accommodate the different procedures performed in each department. Prototypes were developed and tested with healthcare professionals, resulting in a design incorporating a hinge and sliding system to provide flexible, ergonomic support. Surface EMG testing showed that using Lofius correlates with reduced supraspinatus activity, which is important during long ultrasounds, demonstrating its potential to reduce fatigue and prevent injury.

This study concludes that Lofius is a promising starting point for addressing WRMDs in sonography. However, several limitations were acknowledged, including limited clinical testing and inconsistencies in the setup during EMG assessments. Future development should include extended clinical trials, design adjustments for improved support and infection prevention, and exploration of additional force-assistive solutions. Lofius meets the key design requirements identified through user-centred research, providing targeted support during sonography and addressing the most critical risk factor: sustained shoulder abduction.