Shoulder Pain is common and can result from injury (blunt trauma, over extension, dislocation, overuse syndrome, subacromial impingement syndrome representing a spectrum of pathologies, ranging from subacromial bursitis to rotator cuff tendinopathy and full-thickness rotator cuff tear. and various disease conditions (osteoarthritis, rheumatoid arthritis, psoriatic arthritis, and other conditions.
Kelle B & Kozanoglu E (2014), Low-level laser and local corticosteroid injection in the treatment of subacromial impingement syndrome: a controlled clinical trial, Clin. Rehabil. 28(8):762-71.
Abrisham J, et al. (2011), Additive effects of low-level laser therapy with exercise on subacromial syndrome: a randomized, double-blind, controlled trial, Clin. Rheumatol. 30:1341-46.
England S, et al. (1989), Low power laser therapy of shoulder tendonitis, Scand. J. Rheumatol. 18:427-31.
In a controlled clinical trial, Kelle and Kozanoglu (2014) examined the effect of LLLT on pain intensity, shoulder function, and quality of life in 150 patients who were diagnosed with subacromial impingement syndrome. The patients were evaluated four times during the study period: pre-treatment, post-treatment, three months after the first visit, and six months after the first visit with the same investigator evaluating patients at all visits. Pain intensity at rest and pain intensity during activity were evaluated using a visual analog scale (“VAS”) of 0-100. Shoulder function was measured using the University of California at Los Angeles (“UCLA”) rating score, and quality of life was evaluated using the Nottingham Health Profile (“NHP”) scale. The primary outcome measures of the study were pain at rest and pain during activity; secondary outcomes were shoulder functional status and quality of life. Additionally, pain during activity and pain at rest were significantly different between the LLLT group and the sham group at three months and six months after the first visit. Ultimately, the study authors found that LLLT provided significant pain relief and functional improvement in patients with subacromial impingement syndrome.
Abrisham et al. (2011) evaluated the additive effects of LLLT with exercise in comparison to exercise therapy alone in 80 subjects with subacromial syndrome, The study evaluated pain and shoulder range of motion. Pain assessments were based on VAS, while shoulder range of motion was evaluated by a blinded physician. VAS scores between the groups differed significantly (p = 0.00), demonstrating significant pain reduction in the LLLT group as compared to the sham control group. In addition, a significant post-treatment improvement was observed for all active and passive movement in the LLLT group (p = 0.00). Additionally, none of the participants reported any adverse reaction or side effects. Therefore, the study demonstrated that LLLT increased improvement in pain and range of motion in subjects with subacromial syndrome.
England et al. (1989) examined the effect of LLLT on shoulder pain, stiffness, restriction, and function in thirty subjects with supraspinatus or bicipital tendonitis. The England study found that all subjects in the active LLLT group showed improvement in both objective and subjective indices. When the active LLLT was compared to the dummy laser therapy, the study found significant improvement for all of the assessment methods used (p < 0.05). Additionally, as compared to the drug treatment, active LLLT produced statistically-significant changes in objective shoulder movement including active shoulder extension (p < 0.02), flexion (p < 0.01), and abduction (p < 0.005). At the conclusion of the study, all subjects treated with the dummy laser therapy were given the opportunity to cross over to the active LLLT, and all who did so improved.
The Kelle B & Kozanoglu, England, and Abrisham studies as well as others in the scientific literature provide reliable scientific evidence that LLLT has a beneficial effect in those with shoulder pain syndromes.