Does The Type of Exercise Influence Outcome in Rotator Cuff Related Shoulder Pain (RCT-RCRSP)

Context : Musculoskeletal injuries lead to the second largest number of years lived with a disability, just behind mental health problems. Among those, shoulder problems are widespread and become even more common over the years. 70% of the population will experience an episode of shoulder pain during their lifetime and 30% of people over 65 years old live with daily shoulder pain. Unfortunately, the resolution of shoulder pain is often slow and incomplete and about 40 to 50% of symptomatic individuals will still experience pain one year after the onset of their painful episode. Rotator cuff related shoulder pain (RCRSP) is the most common type of injury in this region. This is a broad term that includes subacromial conflict syndrome, rotator cuff tendinopathy, and non-traumatic tears of rotator cuff tendons. There is ample evidence to suggest that physiotherapy exercises are the preferred approach as the first intervention for managing this condition, without having an impact on the quality of recovery. Unfortunately, for many patients, this approach does not lead to a significant decrease in symptoms and may result in a decrease in their quality of life. This lack of therapeutic success could be explained by a multitude of factors: psychosocial, physical, genetic, lifestyle, complex problems related to pain and lack of adherence to the exercise program. Another important element that may explain this lack of improvement is an inappropriate dosage and / or choice of prescribed exercises.

Objectives : The primary objective of this randomized clinical trial is to compare the short, medium, and long-term effects, in terms of symptoms and functional limitations, of three different options (education, strengthening, motor control) for the management of individuals with RCRSP. A secondary objective is to explore the effects of these interventions on shoulder control (acromiohumeral distance), subacromial structures (thickness of the supraspinatus and infraspinatus tendons), kinesiophobia and pain catastrophization.

Methods : 123 individuals between the ages of 18 and 75 with RCRSP for more than 3 months will be recruited and randomly assigned to one of three 12-week interventions: 1) counseling and education only; 2) scapulohumeral and scapulothoracic muscles strengthening exercises; 3) Motor control program paired with global exercises. Before being assigned to their respective group, patients will undergo an initial assessment including self-administered questionnaires on symptoms and functional limitations (QuickDASH, WORC, BPI-SF, TSK, PCS) as well as ultrasound measurements of the shoulder (acromiohumeral distance and thickness of supraspinatus and infraspinatus tendons). The questionnaires will be administered again at 3, 6, 12 and 24 weeks after the inclusion of the participants in the project and the ultrasound measurements will be re-evaluated at 12 weeks. Initial demographic data will be compared (independent t-test and square-test) to establish comparability of groups. Two-way ANOVA analyzes will be used to analyze and compare the effects of the three programs on the primary outcome (QuickDASH) and the other questionnaires (3 interventions x 5 times [0, 3, 6, 12 and 24 weeks]) as well as for the ultrasound measurements (3 interventions X 2 times [0 and 12 weeks]) (SPSS 25, proc GENLIN).

Expected results : The hypothesis is that the two exercises groups will show better results in terms of symptoms and functional limitations compared to the group consisting solely of counseling and education. The motor control program should allow a faster improvement of symptoms and functional limitations than the reinforcement program because, by improving muscular recruitment patterns and scapular kinematics, it will reduce control deficits and thus the probabilities to feel pain. Finally, all groups should show a decrease in kinesiophobia and pain catastrophization, but the exercises groups should result in a larger one, as participants will have to move their arms in ranges previously limited by pain and / or fears related to pain, or perform muscle contractions of near maximal intensity.