If rest, medications and physical therapy do not relieve shoulder pain, subacromial injections of a local anesthetic and a cortisone preparation are recommended. These injections are administered to treat various painful conditions of the shoulder, which may develop due to overuse of the joint, injury or aging. The treatment involves the injection of a mixture of anti-inflammatory medication and anesthesia into the area between the acromion, the area of the scapula that forms the highest point of the shoulder, and the head of the humerus. A subacromial injection may be administered at the front, side or rear of the shoulder. Subacromial injections can be very successful in reducing pain and swelling and restoring a fuller range of motion to the shoulder.
How is a shoulder subacromial injection administered?
Physicians have the patient either stand or sit. The physician identifies the injection space by examining it. Once the physician identifies the subacromial space, they inject a syringe filled with corticosteroid and a local anesthetic into the joint space. The solution should enter the subacromial space without much resistance. The physician may then reposition the needle in the case of any resistance. Using an ultrasonographic technique can enhance the accuracy of the subacromial injection. It may take two to seven days for the steroid medication to provide pain relief.
This technique offers temporary relief of pain and inflammation. Shoulder pain that does not respond to subacromial injections needs to be treated with surgery.
Most patients will experience significant pain relief after a subacromial injection. However, those patients whose severe shoulder pain does not respond to subacromial injections may eventually need to consider undergoing surgery.