Comparision of ultrasound therapy of various durations in the treatment of subacromial impingement syndrome.

[Purpose] A prospective, randomized, single-blind study was performed in order to compare the efficacy of ultrasound treatments of various durations for patients with subacromial impingement syndrome. [Subjects and Methods] One hundred patients who had been diagnosed with subacromial impingement syndrome by clinical examination and magnetic resonance imaging were included in this study. Patients were randomly divided into two groups of fifty patients per group. The first group received 15 sessions of therapeutic ultrasound (4 minutes), superficial heat and transcutaneous electrical stimulation therapy combined with exercise. The second group received the same treatment except that each of the 15 ultrasound sessions were eight minutes in length. The patients were evaluated before and after the treatment. A visual analog scale (VAS) was used to assess pain, the University of California at Los Angeles (UCLA) and Constant Scale were used to assess shoulder function and the Beck Depression Inventory (BDI) was used to quantify depressive symptoms. [Results] There were no statistically significant differences between the groups in age, time since the onset of pain, sex, education and depression levels prior to the treatment. The post-treatment evaluation of patients VAS, UCLA, Constant, and BDI scores showed statistically significant within group improvements. When the two groups were compared, we found no statistically significant differences in the Constant activities of daily living, Constant external rotation, Constant force and BDI scores. However, the second group scored better than the first group in all the remaining parameters. [Conclusion] Ultrasound therapy was found to have beneficial effects on pain and functional status in the treatment of subacromial impingement syndrome. Eight minutes of ultrasound treatment was shown to be more effective than 4 minutes of ultrasound treatment.