Symptoms that suggest a rotator cuff tendinopathy include pain with arm motion overhead, pain at night, and a positive impingement sign (pain during a particular arc of shoulder motion). A common treatment for this problem is a steroid injection into the acromial bursa. The antiinflammatory properties of the steroid medication are designed to reduce swelling and thereby decrease the size of the bursa. An inflamed bursa can be painful but can also take up space in the shoulder causing impingement (pinching) of the rotator cuff tendons.
In a recent study from the University of California, one surgeon found that injecting the shoulder from the front and side (anterior and lateral routes) gave better results than injecting from the back (posterior). This was especially true for women. It turns out that the posterior route was the least accurate when injecting the subacromial bursa in females.
One possible reason for this difference between men and women may be the downward-sloping angle of the acromion. Age did not seem to be a contributing factor. In this study, 75 shoulders were injected in 35 men and 40 women from 24 to 76 years of age. So there was a broad range of ages to compare. The main difference was really gender (male versus female).
When patients fail to get pain relief from a steroid injection for rotator cuff syndrome, it may not be because the injection failed. It could be the injection never reached its intended destination if the surgeon failed to accurately inject the bursa. Pain relief with successful steroid injection is expected to occur within the first hour after injection. A second reason pain relief may not occur is an incorrect diagnosis (the problem may not be a rotator cuff tendinopathy).