Blind or ultrasound-guided corticosteroid injections and short-term response in subacromial impingement syndrome: a randomized, double-blind, prospective study.

Objective: The aim of this study was to compare the accuracy of blind vs. ultrasonography-guided corticosteroid injections in subacromial impingement syndrome and determine the correlation between accuracy of the injection location and clinical outcome.

Design: Forty-six patients with subacromial impingement syndrome were randomized for ultrasonography-guided (group 1, n = 23) and blind corticosteroid injections (group 2, n = 23). Magnetic resonance imaging analysis was performed immediately after the injection. Changes in shoulder range of motion, pain, and shoulder function were recorded. All patients were assessed before the injection and 6 wks after the injection.

Results: Accurate injections were performed in 15 (65%) group 1 patients and in 16 (70%) group 2 patients. There was no statistically significant difference in the injection location accuracy between the two groups (P > 0.05). At the end of the sixth week, regardless of whether the injected mixture was found in the subacromial region or not, all of the patients showed improvements in all of the parameters evaluated (P < 0.05).

Conclusions: Blind injections performed in the subacromial region by experienced individuals were reliably accurate and could therefore be given in daily routines. Corticosteroid injections in the subacromial region were very effective in improving the pain and functional status of patients with subacromial impingement syndrome during the short-term follow-up.