What is shoulder impingement syndrome?

Shoulder impingement syndrome, also called rotator cuff tendonitis, occurs when the tendons or bursa in the shoulder become impinged by the bones in the shoulder.

It is often called “swimmer’s shoulder” or “thrower’s shoulder” because the movements required by these activities can cause the rotator cuff tendons to be impinged as they pass through the sub acromial space in the shoulder. Repetitive pinching in this area can cause inflammation and irritation. As the tendons get more inflamed, they can enlarge, which can further exacerbate the problem.

Shoulder impingement syndrome is a not a condition but a clinical sign for other shoulder conditions, such as bone spurs, shoulder labral tear or strain, shoulder instability, biceps tendonitis, scapula dysfunction and if left untreated, rotator cuff tear.

Types of shoulder impingement syndrome

Shoulder impingement syndrome is classified as external or internal depending on what causes the impingement.

External impingement is also divided into primary and secondary.

  • Primary shoulder impingement — caused by direct impact or a bony spur.
  • Secondary shoulder impingement — result of lack of stabilization in the shoulder joint.

Causes of shoulder impingement syndrome

Many cases of shoulder impingement syndrome occur in athletes such as swimmers, baseball players or tennis players. These athletes use repetitive, over-the-head movements.

Occupations that require over-the-head movements also can cause a shoulder impingement.

Risk factors for shoulder impingement syndrome

There are a variety of factors that can put you at higher risk for shoulder impingement syndrome. Many of these include participating in activities that require repeated overhead movements including:

  • Painting
  • Weight lifting
  • Swimming
  • Tennis 
  • Baseball

Symptoms of shoulder impingement syndrome

The most common symptom of a shoulder impingement is pain that slowly gets worse over time. The pain is located on the side and front of the shoulder joint and is most severe when you perform overhead movements.

Some patients experience pain when the arm is held out to the side and turned outwards. The pain will be persistent and may affect your everyday activities. Motions such as reaching overhead to put on your clothes can cause pain.

Diagnosis of shoulder impingement syndrome

Shoulder impingement syndrome can be diagnosed in a physical exam with your doctor.

Your provider will take a full medical history to determine what your symptoms are, what makes the symptoms most severe as well as if you have had prior shoulder injuries.

Your doctor will perform a full physical exam to evaluate the range of motion in your shoulder, determine where the pain is most severe and what positions cause the most discomfort. An x-ray may be ordered to rule out other shoulder conditions such as arthritis or discover a bone spur.

Treatment of shoulder impingement syndrome

Anti-inflammatory medications are the first-line treatment protocol for shoulder impingement syndrome. Your physician will prescribe the medications for up to eight weeks to ensure he or she fully treats the condition.

If medications do not relieve the pain associated with shoulder impingement, your doctor may recommend other nonsurgical options including:

  • Steroid injection — a cortisone injection may be necessary for more severe shoulder impingements. Cortisone is a powerful anti-inflammatory medication that can be given via injection directly into the affected area. To many cortisone shots can weaken the muscles and tendons, so use sparingly.
  • Physical therapy and rehabilitation — your doctor may recommend working with a physical therapist to develop an exercise program that will strengthen and stretch the shoulder.

If the nonsurgical treatments are not effective, your doctor may recommend a surgical procedure called subacromial decompression.

In a subacromial decompression surgery, your orthopedic surgeon will try to increase the space that is located between the shoulder’s ball-and-socket and the bone above it (acromion). Your surgeon may try one of the following procedures:

  • Acromioplasty — your surgeon will shave the acromion bone down to relieve the pressure on the rotator cuff and bursa.
  • Remove bone spurs — bone spurs rub the rotator cuff and cause impingements in the shoulder, by removing the bone spurs, you can relieve the symptoms of shoulder impingement.

Recovery from shoulder impingement syndrome

Most patients recover from shoulder impingement with rest, anti-inflammatory meds, rehabilitation and avoiding overhead movements. It is important to work with your doctor and physical therapist before returning to your everyday activities and sports.

Results from surgical interventions for shoulder impingement are mostly positive. Approximately 85% of patients return to their previous level of shoulder function. High-performing athletes do not fare as well after a decompression surgery.

Find an orthopedic doctor nearby

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