Comparison of Early Results Between Single and Quadruple Injection of Corticosteroid-local Anesthetic in Patients with Subacromial Impingement

Abstract

Introduction: Subacromial impingement syndrome (SAS) is a painful condition of the shoulder that affects daily activities. The objective of this study was to compare the results of single and quadruple injection (with addition of three other possible trigger points) in patients with SAS. Methods: Sixty-eight patients with the diagnosis of SAS were randomized into two groups. The first group received a single posterior subacromial injection of 1 mL 3 mg Betamethasone (BM) + 9 mL 5 mg 0.5% Bupivacaine (BC). The second group received three extra injections in addition to the posterior subacromial injection; 1 mL BM + 9 mL BC around suprascapular nerve, 1 mL BM + 4 mL BC into the glenohumeral joint and 1 mL BM + 4 mL BC around the bicipital groove. Visual analog scale (VAS) scores, American Shoulder and Elbow Society (ASES) scores and range of motion of the patients were recorded just before the injection and at 3rd, 12th and 24th weeks. Independent samples t-test was used to compare the results of the two groups statistically. Results: Range of motion and ASES scores were found to be higher in the quadruple injection group at all follow-up intervals (p<0.05). VAS scores were statistically better at the third and twelfth week for the quadruple injection group, however the difference between the two groups was statistically insignificant at the sixth month (p=0.42). Conclusion: Quadruple injection resulted in increased range of motion and better functional scores at follow-up intervals up to six months in patients with subacromial impingement.