Shoulder Impingement – The most common reason for shoulder pain

If you’ve ever had shoulder pain or discomfort, you’re not alone. Many people – especially older adults – suffer from shoulder problems. There are many causes, but impingement is one of the most common. Impingement occurs when the rotator cuff is pinched by a part of the shoulder blade (scapula) as the arm is lifted. I’m sure you’ve heard the term “rotator cuff” before. The rotator cuff is a group of four muscles – the supraspinatus, the infraspinatus, the subscapularis, and the teres minor. Unlike your hip joint which is a “ball and socket”, the shoulder has no such structure. Instead, these four muscles cover the “ball” of the shoulder (head of the humerus, which is a bone in the upper arm). These muscles work in tandem to lift and rotate the shoulder. And here’s where the trouble starts. The acromion is the front edge of the shoulder blade. It sits over the front of the humeral head. As the arm is lifted, the acromion rubs or “impinges” on the surface of the supraspinatus muscle of the rotator cuff group. This causes pain and limits movement. Repetitive movement (or “pushing through the pain”) will often result in bursitis (inflammation of the bursa overlying the rotator cuff). Tendonitis (inflammation of the tendon) of the rotator cuff tendons may also result. In some circumstances, repetitive impingement may result in a partial tear of the rotator cuff. If you are experiencing these symptoms, you need to talk to your doctor.

Risk Factors/Prevention

Impingement is common in both young athletes and middle-aged people. Young athletes who use their arms overhead for swimming, baseball and tennis are particularly vulnerable. Also, those who perform repetitive lifting or overhead activities using the arm such as paper hanging, construction or painting are also susceptible to impingement pain. Finally, pain may also develop as the result of minor trauma or spontaneously with no apparent cause. In older patients, it may occur as a result of poor posture – especially in women with osteoporosis.

Symptoms Of Shoulder Impingement

Luckily, beginning symptoms may be mild. However, patients frequently do not seek treatment at this early stage because the pain has not yet reached a level where it is severe. In fact, you may first be aware of minor pain that’s present both with activity and at rest. You may also have pain radiating from the front of the shoulder to the side of the arm. Or you may notice sudden pain with lifting and reaching movement. All of these symptoms could be a sign of shoulder impingement. Impingement commonly causes local swelling and tenderness in the front of the shoulder, pain and stiffness when you attempt to lift your arm and pain when you lower your arm from an elevated position. As the problem progresses, you may have pain at night. Strength and motion will be diminished. You may have difficulty with activities that place the arm behind the back, such as buttoning or zippering. And in advanced cases, loss of motion may progress to a “frozen shoulder.” In acute bursitis, the shoulder may be severely tender, with all movement limited and painful.

Diagnosis

To diagnose shoulder impingement, an orthopaedic surgeon reviews the symptoms and physically examines the shoulder. He or she may need X-rays. A special X-ray will sometimes show a small bone spur on the front edge of the acromion. At that point, the doctor may request further imaging studies, such as an MRI (magnetic resonance imaging). These can show fluid or inflammation in the bursa and rotator cuff. In some cases, partial tearing of the rotator cuff will be identified.

Treatment Options

Initial treatment is conservative. The doctor may suggest that you rest and avoid overhead activities. He or she might prescribe a course of oral nonsteroidal anti-inflammatory medication. Many patients benefit from injection of local anesthetic and a cortisone preparation to the affected area. The doctor might also recommend a program of supervised physical therapy. For instance, stretching exercises can help improve range of motion in a stiff shoulder. Also, posture re-education might be taught. Scapular strengthening exercises may also be performed. Treatment may take several weeks to months. Many patients experience a gradual improvement and return to function.

Treatment Options: Surgical

When conservative treatment does not relieve pain, the doctor may recommend surgery. The goal of surgery is to remove the impingement and create more space for the rotator cuff. This allows the humeral head to move freely in the subacromial space and to lift the arm without pain. The most common surgical treatment is subacromial decompression or anterior acromioplasty. This may be performed by either arthroscopic or open techniques. In an arthroscopic procedure, two or three small puncture wounds are made. The joint is then examined through a fiberoptic scope connected to a television camera. Finally, small instruments are used to remove bone and soft tissue. Open surgery requires placement of a small incision in the front of the shoulder. This allows for direct visualization of the acromion and rotator cuff. In most cases the front (anterior) edge of the acromion is removed along with some of the bursal tissue. The surgeon may also treat other conditions present in the shoulder at the time of impingement surgery. These can include acromioclavicular arthritis, biceps tendonitis or a partial rotator cuff tear.

Rehabilitation

After surgery, the arm may be placed in a sling for a short period of time. This allows for early healing. As soon as the patient is comfortable, the sling can be removed and exercise and use of the arm can begin. The surgeon will most likely refer a patient to physical therapy for rehab. Based on your needs and the findings at surgery will determine a particular physical therapy protocol. This will include exercises to regain range of motion of the shoulder and strength of the arm. It may take two to four months to achieve full range of motion and complete relief of pain. Yes, shoulder impingement can be a painful condition. However, like most ailments, if caught early, many treatment options can be effective at alleviating the pain associated with this very common condition.