A new study carried out by US researchers has found that NSAID injections are better than corticosteroid injections for relieving shoulder pain. A single injection of the nonsteroidal anti-inflammatory drug (NSAID) ketorolac demonstrated superior pain-relieving qualities compared to corticosteroid injections when treating patients with shoulder impingement syndrome. The study was a double-blind, randomized research project and the paper was recently presented to attendees of the American Orthopaedic Society for Sports Medicine (AOSSM) 2011 Annual Meeting.
Shoulder pain can be caused by a number of conditions, some acute, some chronic, and is often accompanied by neck pain and upper back pain, particularly in conditions such as spinal stenosis, degenerative disc disease and pinched nerves, or even brachial plexus injury. This study looked specifically at subacromial impingement syndrome however, a condition involving trapped tendons when the arm is elevated or the shoulder rotated internally, and which possibly leads to rotator cuff tear if unaddressed. Further problems may also develop, such as impingement of the infraspinatus tendon and biceps tendonitis.
Subacromial impingement syndrome can also be caused by arthritis, with osteophyte growth implicated in some cases. Removal of the osteophytes may be necessary to address the problem, where it is mechanical rather than simply inflammatory in nature. The condition is, however, normally treated with corticosteroid injections and possible physical therapy. Unfortunately, such injections come with a risk of tendon rupture, adverse changes in articular cartilage, and the atrophy of subcutaneous tissue (thinning of the tissue under the skin). During the study, forty-eight patients with isolated external shoulder impingement syndrome were assigned to a group receiving either 6cc of 1% lidocaine with epinephrine and 40mg triamcinolone (the corticosteroid group), or a group receiving the same dose of lidocaine (without the epinephrine) and 60mg ketorolac (the NSAID group). Both groups improved after four weeks in terms of pain and mobility but the NSAID group had a mean improvement of 7.15 compared with 2.13 on the University of California– Los Angeles Shoulder Assessment Score.
NSAID Shots for Shoulder Pain – Risks and Benefits
In addition, the group receiving NSAID shots for shoulder pain had an increase in strength on forward flexion, whereas the steroid group showed a marginal decrease in strength. Patients in the NSAID group were also more satisfied with their treatment than those receiving steroid shots. The researchers observed that, whilst both groups had initial improvements, only the NSAID group showed significant effects over a longer period of time. Using NSAID injections is preferable to using corticosteroid injections as they do not have the same side-effects of tissue loss, and cartilage damage and may be given more frequently, whereas corticosteroid shots are limited in terms of frequency. There are some potential disadvantages to NSAID shots for shoulder pain however, including complications in patients with kidney dysfunction, and possible bleeding. Taking oral NSAIDs alongside NSAID injections is also advised against, and those with gastric ulcers are not candidates for this treatment as it may exacerbate their condition.
The effect of the NSAID shots at relieving shoulder pain is thought due to the anti-inflammatory action they provide and ketorolac injections have been popular in sports medicine for many years for their ability to reduce pain. Although the study is unlikely to result in a switch from corticosteroid treatment for shoulder pain, or indeed neck pain, it does offer an alternative, particularly in cases where the steroid injections have failed to provide shoulder pain relief.
American Orthopaedic Society for Sports Medicine (AOSSM) 2011 Annual Meeting: Abstract 34. Presented July 10, 2011.