Could a Feedback Device Help Manage Work-related Shoulder Disorders?

Work-related shoulder pain is a common problem with significant socio-economic repercussions. The impact of these disorders on workers is considerable, particularly in terms of pain, disability and reduced quality of life. Several occupational factors may explain the onset of these disorders, such as changes in the work environment, physical demands, psychosocial factors specific to the occupational context and the age of workers. The lack of quantitative measurement tools to assess the physical demands of work over an extended period of time is sorely felt. Recently, our team developed a wearable feedback device, similar to a watch worn on the arm, which measures shoulder movements and muscle activity, transforming this real-time data into clinical indicators. These indicators provide immediate feedback to workers, enabling them to better understand the physical demands of their tasks and adapt accordingly. If this device proves effective in reducing physical demands, it could become a valuable tool for guiding workplace assessments and interventions. However, this device has not yet been tested on workers with shoulder pain. For this reason, a two-part pilot study is needed to understand user needs, assess ease of use and the feasibility of implementing the device. The first component will consist of a pilot clinical trial involving 42 workers suffering from shoulder pain, divided into two groups: one group will use the feedback device for 2 weeks, while the other group will continue to work without intervention. The second phase will analyze the experience of participants who have used the device.

The objectives of this pilot study are (a) to evaluate the feasibility of implementing the SWL in the workplace and conducting a large-scale randomized clinical trial (RCT) by assessing recruitment success, intervention adherence, acceptability of the technology, the research team's capacity to refine the SWL, and (b) to explore the SWL capacity to reduce disability, pain, work limitations, and physical work demands while increasing pain self-efficacy among workers with WRSDs.

Eligibility Criteria:
Inclusion Criteria:

1. Adult (≧ 18 years) employed full-time (minimum of 35 hours per week).
2. Experiencing work-related shoulder disorders (WRSDs), with minimal score of 14 points on the for the abbreviated version of the Disability of the Arm Shoulder and Hand questionnaire (QuickDASH), stemming from a diagnosis of rotator cuff-related shoulder pain (RCRSP), shoulder osteoarthritis (SOA) or rheumatoid arthritis (RA) involving the shoulder.
3. Symptoms persisting for more than 6 weeks.

Diagnosis-specific criteria:

1. RCRSP: presence of a painful arc in flexion or abduction, a positive Neer sign or Hawkins-Kennedy Test, and pain with resisted humeral external rotation or abduction, or a positive Jobe Test;
2. SOA: diagnosis based on clinical findings (e.g., activity-related pain, reduced range of motion particularly external rotation and function, worsening night/rest pain) and radiologic findings (e.g., osteophytes, joint space narrowing, subchondral sclerosis, cyst formations, and humeral head deformities);
3. RA involving the shoulder: confirmed diagnosis according to the American College of Rheumatology criteria.

Both SOA and RA diagnoses will be confirmed by a physician.

Exclusion Criteria:

1. clinical signs of a massive rotator cuff tear (e.g., pseudoparesis or pseudoparalysis, passive elevation intact but active limited to \<90°, without neurologic deficit);
2. acute traumatic rotator cuff tears, fractures, adhesive capsulitis (characterized by night pain, pain with sudden or unexpected movements, global loss of active and passive range of motion), or shoulder instability (evidenced by a combination of orthopaedic tests such as apprehension and relocation tests, Jerk, Kim and posterior tests, along with and clinical signs like neuromuscular function impairment, history of instability, lesion mechanisms, worries that their shoulder could dislocate during activities);
3. distal neurovascular symptoms (e.g., thoracic outlet syndrome, venous thromboembolism);
4. previous shoulder surgery;
5. corticosteroid injection administered within the past 3 months;
6. absenteeism from work.