High Intensity Versus Low Level Laser Therapy in Treatment of Patients With Subacromial Impingement Syndrome: A Randomized, Double-blind, Controlled Trial.

Shoulder pain is the third most common musculoskeletal problem after lumbar and neck diseases in clinical practice, and the most common cause of shoulder pain is subacromial impingement syndrome. The main goal of treatment is to reduce pain and to solve the mechanical problem that causes functional impairment. Low-level laser treatment is an increasingly used treatment modality in the treatment of subacromial impingement syndrome as in many musculoskeletal diseases, as it promotes cell proliferation and tissue regeneration by its anti-inflammatory and photobiostimulation properties. Also, High-intensity laser therapy is a treatment method that is gaining popularity in the recent years. These ultra-short impulses effect a deep action in the biological tissue (3-4 cm), with a homogeneous distribution of the light source in the irradiated soft tissue, but without excessive thermal enhancements. It reduces pain and edema with photomechanic effects in deep tissues. As far as the investigators know, there are no studies comparing these two treatment modalities in subacromial impingement syndrome yet. This study was planned to compare the efficacy of High-intensity laser therapy and low-intensity laser therapy in treatment of patients with subacromial impingement syndrome.