If pain medication doesn’t provide relief, doctors may recommend an injection of medication directly into the arthritic joint. Our orthopaedic and rheumatologic specialists often use ultrasound—in which high-frequency sound waves create images of the inside of the body—to guide the injection precisely into the joint, ensuring that the medication has maximum effect.
Corticosteroids are anti-inflammatory medications that may provide pain relief when injected directly into the shoulder joint. Corticosteroids reduce inflammation, which is part of the body’s immune system response and causes pain and swelling.
Typically, doctors inject a small amount of anesthetic in addition to the corticosteroids to provide short-lasting but immediate pain relief. The anesthetic wears off a few hours after the injection, at which time shoulder pain may return. The corticosteroid solution begins to work two to three days later. In some people, a corticosteroid injection provides pain relief that lasts for many months, although in others it can be less effective.
Doctors recommend no more than two or three corticosteroid injections in the shoulder joint. If used too frequently, corticosteroid use may lead to infection, discoloration at the injection site, or a weakening of the shoulder structure that increases the risk of an injury, such as a torn tendon.
Hyaluronic Acid Injection
The shoulder joint contains a small amount of a gel-like substance called synovial fluid. This fluid cushions and lubricates the joint. Synovial fluid has a component called hyaluronic acid, which helps to make it viscous, or sticky and thick. If synovial fluid thins out, it becomes less effective as a lubricator.
Doctors at NYU Langone can inject hyaluronic acid—typically produced in a laboratory—into synovial fluid in the shoulder joint to increase the fluid’s viscosity and improve the joint’s gliding motion. This improved joint function may provide pain relief that lasts for weeks or months. Doctors recommend limiting hyaluronic injections to one per year. This procedure has been found to be safe and rarely has side effects.
Hyaluronic acid injections bring relief for some people, but this technique has not been scientifically proven to have positive effects, and doctors can’t predict when an injection is going to be effective. Our doctors are continuing to explore the effectiveness of these injections.
Until they are approved by the U.S. Food and Drug Administration as a treatment for osteoarthritis of the shoulder, hyaluronic acid injections remain an experimental treatment option. Most insurance companies do not cover the cost of the procedure.
Recovery from Therapeutic Injections
Most people return home an hour or two after the injections. The site of injection may be swollen or tender for one or two days, and doctors may recommend an over-the-counter pain medication to relieve pain and reduce swelling.