Purpose:
Shoulder pain is the third most common musculoskeletal disorder, and impaired diaphragmatic function may lead to altered arthrokinematics and contribute to symptom development in patients with shoulder pain. This study aimed to investigate the effect of adding myofascial release of the diaphragm muscle to routine physiotherapy on pain, functional disability, and quality of life in these patients.
Methods:
This double-blind randomized clinical trial included 25 patients allocated into two groups: a control group (routine physiotherapy + sham diaphragm release) and an intervention group (routine physiotherapy + active diaphragm myofascial release). Both groups received six treatment sessions over two weeks. Pain intensity, functional disability, and quality of life were assessed using the Visual Analogue Scale (VAS), Shoulder Pain and Disability Index (SPADI), and Short Form-12 Health Survey (SF-12), respectively. Paired and independent t-tests were used for within- and between-group comparisons, and Cohen’s d was calculated to determine effect sizes.
Results:
Pain intensity at rest, during activity, and during night sleep, as well as SPADI scores, significantly decreased in both intervention and control groups from pre- to post-treatment (p < 0.001); however, the effect size was greater in the intervention group. The mental component score (MCS) of quality of life significantly improved in the control group (p < 0.001), with an effect size of 0.78. The physical component score (PCS) also showed a significant increase in the control group (p = 0.01), with a large effect size of 1.1.
Conclusion:
Active myofascial release of the diaphragm combined with routine physiotherapy and sham manual contact can effectively reduce pain and disability in patients with chronic shoulder pain. However, no sufficient evidence was found to support a differential effect between active and sham diaphragm release on pain and disability outcomes. In the present study, the sham-contact group demonstrated greater improvements in quality of life.