Evaluation of the effectiveness of dexamethasone iontophoresis in patients with subacromial impingement syndrome

Background: Subacromial impingement syndrome is the most common shoulder disease in individuals. There is no study evaluating the effectiveness of steroid iontophoresis in subacromial impingement syndrome. We aimed to assess the effectiveness of dexamethasone iontophoresis as treatment for impingement syndrome with respect to pain and function. Methods: Forty-six patients with subacromial impingement syndrome were recruited to the study and divided randomly into two groups (21 patients in iontophoresis group and 25 patients in control group). Demographic, clinical features and MRI findings of patients were recorded. Detailed physical examination of all patients were performed and Numerical rating scale (NRS) during rest and exercise, The Disabilities of the Arm, Shoulder and Hand (DASH) scores were recorded at baseline, week 2 and week 6. Both group received physiotherapy program for ten days. Additionally the patients in iontophoresis group recieved dexamethasone iontophoresis (1 mg dexamethasone per 1 g administered under the active electrode) with an intensity of 0.1-0.2 mA/cm(2) galvanic current for ten days. Results: No significant difference was observed between the groups in terms of gender, job status, MRI findings, painful shoulder and pain duration. Baseline range of motion, Neer, Hawkins, Yocum and painful arc tests, numerical rating scale (NRS) and DASH scores were similar between groups. A significant improvement was found in terms of the NRS (resting and exercise) and DASH scores at week 2 and week 6 in both group (p < 0.001). A significant difference was found in terms of improvement NRS (resting) and DASH scores between baseline and week 6 in iontophoresis group (p = 0.007, p = 0.011 respectively). Conclusions: Adding dexamethasone iontophoresis to physiotherapy for patients with subacromial impingement syndrome seems to provide a better clinical and functional improvement. (C) 2020 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.