Optimal dose of intra-articular corticosteroids for adhesive capsulitis: a randomized, triple-blind, placebo-controlled trial.

BACKGROUND

Intra-articular corticosteroid injection is a commonly used therapy for adhesive capsulitis, but there are only few studies that compare the efficacy of corticosteroids according to different doses.

PURPOSE

To determine whether intra-articular injections with a high-dose corticosteroid improves pain and function in patients with adhesive capsulitis better than a low dose or a placebo.

STUDY DESIGN

Randomized controlled clinical trial; Level of evidence, 1.

METHODS

Participants (n = 53) with primary adhesive capsulitis in the freezing stage were randomly assigned to receive ultrasound-guided intra-articular injections with 40 mg triamcinolone acetonide (high-dose group, n = 20), 20 mg triamcinolone acetonide (low-dose group, n = 20), or placebo (n = 13). After a single injection, participants were all instructed to carry out a home exercise program. The outcome measures included the Shoulder Pain and Disability Index (SPADI), visual analog scale (VAS) for average shoulder pain level, and passive range of motion including flexion, abduction, extension, external rotation, and internal rotation before treatment and at weeks 1, 3, 6, and 12 after treatment.

RESULTS

There were no significant differences in demographic and clinical characteristics at baseline between the 3 groups. Repeated-measures analysis of variance and post hoc tests showed improvement in SPADI and VAS scores and in flexion, abduction, and internal rotation especially for the low- and high-dose groups compared with the placebo. Yet, no significant difference was found between the 2 different corticosteroid dose groups.

CONCLUSION

We assessed the efficacy of corticosteroid injections according to 2 different doses that are most widely used in intra-articular injections for adhesive capsulitis. This study shows that there were no significant differences between the high- and low-dose corticosteroid groups, indicating the preferred use of a low dose in the initial stage.