Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis

Background: A corticosteroid injection in the glenohumeral joint conducted blindly is technically demanding with a low rate of accuracy despite satisfactory clinical outcomes in the treatment for adhesive capsulitis. This study prospectively compared the clinical outcomes of patients with idiopathic adhesive capsulitis treated by a single corticosteroid injection in different locations of the shoulder. Materials and methods: We randomly assigned 191 patients with adhesive capsulitis to 1 of 4 groups based on corticosteroid injection location: group I, subacromial; group II, intra-articular; group III, intra-articular combined with subacromial space; and group IV, medication. Pain relief and patient satisfaction were assessed with a visual analog scale and functional outcomes were evaluated with the American Shoulder and Elbow Surgeons score up to 24 weeks after treatment. Results: Patients treated with corticosteroids achieved faster pain relief and had greater satisfaction levels than patients in group IV during the 16 weeks after treatment. However, no significant difference in pain scores was observed among the 4 groups at 24-week follow-up visits (P = .670). Shoulder motion and function improved in all groups at final follow-up. However, shoulder motion in the injection groups recovered faster than that in group IV. At 24 weeks after treatment, no significant differences in shoulder motion or functional outcomes were found among the 4 groups (P = .117). Conclusions: The efficacy of a single corticosteroid injection was not found to be related to the site of injection. However, a single corticosteroid injection provided faster pain relief, a higher level of patient satisfaction, and an earlier improvement in shoulder motion and function than medication in patients with adhesive capsulitis.