Anatomy and Function
Shoulder impingement is a common condition found in the adult shoulder that may result in significant shoulder pain. Shoulder impingement and bursitis is caused by pressure on the rotator cuff tendon by part of the shoulder blade (acromion) while the arm is brought overhead.

The rotator cuff is a group of four muscles that come together forming a strong tendon (cuff) that inserts on the top of the upper arm bone (humerus). The four muscles that come together to form the rotator cuff are the supraspinatus, infraspinatus, teres minor, and subscapularis. The rotator cuff has a very important function: it holds the humerus in position to allow lifting and rotating of the arm. It is especially important in overhead activities

Shoulder Impingement

The acromion is the front edge of the shoulder blade. It sits over and in front of the humeral head. As the arm is lifted, the acromion rubs, or “impinges” on, the surface of the rotator cuff. This impingement of the rotator cuff tendon against the acromion leads to inflammation of the bursa overlying the rotator cuff (bursitis) and eventually may lead to tendonitis or tear of the cuff itself. This causes pain and limits movement. Moreover, it can eventually cause tearing of the rotator cuff tendon. Frequently a prominent and impinging acromion is found in combination with a tear of the rotator cuff.

Symptoms
Shoulder impingement may manifest itself in various ways. Most commonly it starts as a minor pain that may be present with activity and occasionally at rest; however, over time it may advance to become more severe. The pain may start from the shoulder and radiate down the side of the arm. Certain activities such as lifting the arm overhead or reaching backwards are particularly painful. Impingement may frequently be seen in athletes while throwing a football or during a tennis or volleyball serve.

Eventually as impingement continues it may lead to bursitis and tendonitis that may cause shoulder swelling and tenderness. Holding the arm overhead may become increasingly difficult and painful. This may lead to an inability to fully move the shoulder in all directions and strength may also be affected. Over time if left untreated, shoulder bursitis may lead to stiffness and significant loss of motion (frozen shoulder).

Cause:
Impingement is usually a result of repetitive lifting or overhead activities that may be sport or work related. Athletes who frequently use their arms overhead such as in baseball, tennis, volleyball, and swimming are more prone to develop shoulder impingement. Workers who regularly perform overhead activities such as painting or construction are also more vulnerable to developing impingement and bursitis. However, occasionally it may also develop without particular reason, but rather may be due to an anatomic variance in the shape and size of the acromion.

Shoulder Impingement Treatment

Conservative Treatment
A series of xrays is important to evaluate for any bone spurs or arthritis that may contribute to the symptoms. Your Los Angeles orthopedic surgeon may also want to obtain an MRI of the shoulder if there is concern for a rotator cuff tear.

Upon diagnosis of shoulder impingement and bursitis, Dr. Samimi prefers to start with the most conservative treatments first. Activity modification is important including avoidance of overhead activities. Oral anti-inflammatory (NSAIDs) medications may be prescribed to help reduce pain and inflammation. Physical therapy may help increase range of motion and alleviate symptoms by strengthening and stretching the surrounding musculature. A steroid injection is also frequently used in collaboration with the above treatments. The majority of shoulder impingement will gradually improve with conservative treatment.

Shoulder Impingement Surgery

Surgery
In circumstances where conservative treatment has failed to provide adequate relief, shoulder impingement surgery may be recommended. Dr. Samimi specializes in the treatment of shoulder impingement and bursitis using minimally invasive technique of shoulder arthroscopy. By performing shoulder arthroscopy, your orthopedic surgeon can fully examine the shoulder and subacromial space to evaluate the exact source of the impingement and adequately treat it using only a few small incisions. Surgery for impingement involves trimming the prominent portion of the acromion bone and removing the inflamed bursal tissue. This allows more space for the rotator cuff to move freely and prevents further pinching of the cuff that may predispose to tearing.

What happens during the procedure?

Shoulder Impingement Surgery

Shoulder arthroscopy is a surgical procedure used to visualize, diagnose, and treat problems inside a joint. The procedure involves making a small incision in the skin and inserting a pencil-sized arthroscope into an injured or damaged joint. The arthroscope’s tiny camera and instrumentation allow Dr. Samimi to see inside the joint in a magnified and illuminated manner to accurately diagnose the extent and pattern of the impingement and bursitis and repair it.

After evaluating the shoulder joint, the surgeon places the camera in the space above the rotator cuff tendons, called the subacromial space. The surgeon can check the area above the rotator cuff, clean out inflamed or damaged tissue, and remove a bone spur (acromion spur) that may be causing impingement of the tendon.

At the end of the shoulder surgery, the incisions will be closed with stitches and covered with a dressing (bandage). Typically patients will go home the same day in a sling followed by a course of physical. The bandage will be removed and showering is allowed 2 days after surgery. The small incisions will simply be covered by a band-aid.

Dr. Samimi will take pictures of the procedure from the video monitor to show you what was found and what was done during the shoulder impingement surgery. He feels it is important for you to understand the nature of the problem and exactly what was done to fix it.

Arthroscopy is almost always performed as outpatient surgery and offers such benefits as reduced risk, fewer complications, less postoperative pain, less recovery time, and far less scarring. Using this minimally invasive procedure we perform rotator cuff repair with excellent results.

For detailed information about this condition and shoulder impingement treatments please visit:AAOS Online Service Fact Sheet – Shoulder Impingement