Even though one of the most common treatments for shoulder pain are corticosteroid injections, only a few high-quality studies to research there effectiveness and duration of action have been conducted. However, a new investigation of the two most commonly corticosteroid doses administered for shoulder pain has discovered that lower doses are just as effective as higher ones for pain reduction, duration of efficacy and improved range of motion. The results of the investigation are due to be published in the December issue of the Archives of Physical Medicine and Rehabilitation.

79 individuals with at least one month’s duration of shoulder pain were enrolled in the randomized, triple-blind, placebo-controlled clinical trial. Participants were randomly assigned to one of three groups. 27 patients received 40 mg dose of triamcinolone acetonide, 25 patients received a 20 mg dose and 27 patients received a placebo injection. All participants were followed up at two, four and eight weeks following treatment. All injections performed in the study used ultrasound guidances to insure proper placement of the treatment in the bursa.

After treatment participants were given a Shoulder Disability survey and asked to rate their degree of pain on a scale of 0 to 10. In addition, participants were asked to move their shoulders slowly until they felt pain. The researchers measured thire Active Range of Motion (AROM) in four different directions – abduction, forward flexion, external rotation of the shoulder while standing and internal rotation.

Compared with pretreatment (within-group comparisons), the researchers discovered that participants in both the high dose (40 mg) group and the low dose (20 mg) group showed the same improvement in pain, disability, and AROM, those in the placebo group showed no difference. The results showed there were no considerable differences between the high dose group and the low dose group, however, as higher doses might increase the prevalence of local and general complications, the investigators suggest a lower dose at the initial treatment stage.

Lead researcher Seung-Hyun Yoon, MD, PhD, Assistant Professor, Department of Physical Medicine and Rehabilitation, Ajou University School of Medicine, Suwon, Republic of Korea, explained:

“There has been no guidance for adequate corticosteroid doses during subacromial injection. Physicians have depended mainly on their experience for the selection of dose. This is the first study to assess the efficacy of corticosteroid according to two different doses, which are most widely used in subacromial injection for participants with periarticular shoulder disorders. Initial use of a low dose is encouraged because there was no difference in efficacy according to the dose. And the effect of corticosteroid lasted up to 8 weeks.”

Written by: Grace Rattue