Impingement Could Be to Blame for Shoulder Pain

Speaking from a biased opinion, the shoulder may be the most complex and interesting joint in the entire body. What most people consider the shoulder joint is actually made up of three joints, as well as a special joint called an articulation between the shoulder and the chest wall. It's the complex interaction between these joints that gives the shoulder and upper extremity its combination of incredible power, fine motor control and extreme range of motion. All this complexity and motion comes at a price though. Shoulder pain is second only to back pain as a presenting complaint for musculoskeletal care. Most of us will likely have an episode of shoulder pain at some point that will need either treatment or will require us to miss work! The personal and economic impact of shoulder pain and conditions is tremendous. Impingement syndrome inflammation related to the fraying of the rotator cuff is one of the most common conditions I treat in my practice.

What is Impingement?

The story of shoulder pain starts and ends with four small stabilizer muscles we collectively term the rotator cuff. As a shoulder specialist, more than 80 percent of the conditions I treat relate to this critical structure. The rotator cuff consists of four tendons that merge together to form a cuff of tissue that surrounds and stabilizes the joint. Its primary function is to stabilize the ball and socket joint through the entire range of motion. Anatomically, it's located in a tight space between the collar bone, top of the shoulder blade and the ball of the ball-and-socket joint. This space is tight enough that there's often significant fraying or rubbing on the surface of the tendon. This is called impingement. In normal situations, there is a small sac or bursa filled with fluid that sits between the bone and the tendons, lubricating them and preventing tendon damage. Unfortunately, as we age, this space tends to get tighter. Natural aging produces bone growths (called bone spurs) that encroach into the space. The impingement can worsen to the point it begins to produce pain and tendon damage. Inflammation to the bursae (bursitis) commonly occurs and can become quite painful. This collection of problems is what we term “impingement syndrome.” It's also commonly called bursitis or tendinitis.

What is Really Going On?

The primary problem in impingement syndrome is related to inflammation. As the bursa swells and loses its lubricating function, the tendon begins to fray and motion becomes painful. Initially, patients experience pain only with certain movements, usually overhead. As the problem progresses they may begin to have pain with all movements. Night pain is a common problem and is often the symptom that brings people to medical attention.

Treatment Options

In its early stages, impingement responds well to over-the-counter treatments such as ibuprofen or Naprosyn. A simple exercise program (called shoulder conditioning) can improve mechanics and reduce swelling. Early impingement in younger patients responds well enough that these simple measures may cure the problem more than 80 percent will get better. However, patients who experience a bout of impingement are more likely to have subsequent problems.

Steroid Injections

Cortisone deserves its own section because it can be somewhat controversial. Cortisone is a potent steroid that has been in general use for decades. It can be given orally, by injection directly to the joint or through an I.V. and is used to treat a variety of medical conditions. In the orthopedic world, it's most often given by way of injection. Cortisone is a powerful anti-inflammatory and reduces tissue swelling and irritation. In the case of the shoulder, it can reduce swelling in the bursa and rotator cuff tendons, and open the space around the tendons to allow more natural motion. In the right setting, a shot of cortisone can be curative! With impingement, for example, 85 percent of patients under age 50 will have at least one year of relief after a single injection. But cortisone can have side effects as well. Infections occur infrequently, but can be quite difficult to manage. Tissue damage and worsening of degenerative conditions is also seen, but usually after repeated dosage over a relatively short time period. The best source of advice about appropriate use of cortisone is your physician.

Surgical Care

Up to 15 percent of patients will fail to respond to conservative management. When pain and disability persist despite appropriate care, outpatient surgery can cure or improve the problem. The surgery is done using the arthroscope. Through keyhole incisions, excess bone, bone spurs and bursa can be removed freeing the space around the rotator cuff for normal motion. In addition, tendon damage can be addressed and more normal anatomy restored. Most patients experience significant relief and can be back to normal activities in 6-10 weeks.

• Michael Daines, MD, is a board-certified orthopedic surgeon and fellowship-trained shoulder specialist practicing at West Idaho Orthopedics and Sports Medicine and West Valley Medical Center in Caldwell. To learn more about Dr. Daines or any West Valley provider, visit westvalleyisbetter.com.