One of the most common physical complaints is shoulder pain. Your shoulder is made up of several joints combined with tendons and muscles that allow a great range of motion in your arm. Because so many different structures make up the shoulder, it is vulnerable to many various problems. The rotator cuff is a frequent source of pain in the shoulder. Subacromial impingement is the most common cause of shoulder pain and accounts for 44-65% of shoulder disorders.

Description

The rotator cuff is a common source of pain in the shoulder. Pain can be the result of:

• Tendinitis. The rotator cuff tendons can be irritated or damaged.
• Bursitis. The bursa can become inflamed and swell with more fluid causing pain.
• Impingement. When you raise your arm to shoulder height, the space between the acromion and rotator cuff narrows. The acromion can rub against (or “impinge” on) the tendon and the bursa, causing irritation and pain.

Cause

Rotator cuff pain 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. Those who do repetitive lifting or overhead activities using the arm, such as paper hanging, construction, or painting, are also susceptible.
Pain may also develop as the result of a minor injury. Sometimes, it occurs with no apparent cause.

Symptoms

Rotator cuff pain commonly causes local swelling and tenderness in the front of the shoulder. You may have pain and stiffness when you lift your arm. There may also be pain when the arm is lowered from an elevated position.
Beginning symptoms may be mild. Patients frequently do not seek treatment at an early stage. These symptoms may include:
• Minor pain that is present both with activity and at rest
• Pain radiating from the front of the shoulder to the side of the arm
• Sudden pain with lifting and reaching movements
• Athletes in overhead sports may have pain when throwing or serving a tennis ball
As the problem progresses, the symptoms increase:
• Pain at night
• Loss of strength and motion
• Difficulty doing activities that place the arm behind the back, such as buttoning or zippering
If the pain comes on suddenly, the shoulder may be severely tender. All movement may be limited and painful.

What do we know now?

 • Subacromial impingement is the first stage of rotator cuff disease which is a continuum of disease from
◦ impingement and bursitis
◦ partial to a full-thickness tear
◦ massive rotator cuff tears
◦ rotator cuff tear arthropathy
• Associated conditions
◦ hook-shaped acromion
◦ os acromiale
◦ posterior capsular contracture
◦ scapular dyskinesia
◦ tuberosity fracture malunion
◦ instability

Classification of Impingement based on possible causes.

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Medical History and Physical Examination

After discussing your symptoms and medical history, Prof Imam will examine your shoulder. He will check to see whether it is tender in any area or whether there is a deformity. To measure the range of motion of your shoulder, Prof Imam will have you move your arm in several different directions. Prof Imam or a member of the team will check for other problems with your shoulder joint. They may also examine your neck to ensure that the pain is not coming from a “pinched nerve” and rule out other conditions, such as arthritis.

Imaging Tests

X-rays. Because x-rays do not show the soft tissues of your shoulder like the rotator cuff, plain x-rays of a shoulder with rotator cuff pain are usually typical or may show a small bone spur. A special x-ray view, called an “outlet view,” sometimes will display a small bone spur on the front edge of the acromion.

Magnetic resonance imaging (MRI) and ultrasound. These studies can create better images of soft tissues like the rotator cuff tendons. They can show fluid or inflammation in the bursa and rotator cuff. In some cases, partial tearing of the rotator cuff will be seen.

Treatment

The goal of treatment is to reduce pain and restore function. In planning your treatment, Prof Imam or a team member will consider your age, activity level, and general health.

Nonsurgical Treatment

In most cases, initial treatment is nonsurgical. Although nonsurgical treatment may take several weeks to months, many patients experience a gradual improvement and return to function.

Rest. Prof Imam or a team member may suggest rest and activity modification, such as avoiding overhead activities.
Non-steroidal anti-inflammatory medicines. Drugs like ibuprofen and naproxen reduce pain and swelling.
Physical therapy. A physical therapist will initially focus on restoring normal motion to your shoulder. Stretching exercises to improve range of motion is very helpful. Suppose you have difficulty reaching behind your back. In that case, you may have developed tightness of the posterior capsule of the shoulder (capsule refers to the inner lining of the shoulder and posterior refers to the back of the shoulder). Specific stretching of the posterior capsule can be very effective in relieving pain in the shoulder.
Once your pain improves, your therapist can start you on a strengthening program for the rotator cuff muscles.
Steroid injection. An injection of a local anaesthetic and a cortisone preparation may be helpful. Cortisone is a very effective anti-inflammatory medicine. Injecting it into the bursa beneath the acromion can relieve pain.

Surgical Treatment

When nonsurgical treatment does not relieve pain, Prof Imam may recommend surgery.
The goal of surgery is to create more space for the rotator cuff. To do this, Prof Imam will remove the inflamed portion of the bursa. He may also remove part of the acromion. This is also known as a subacromial decompression. These procedures are done with an arthroscopic technique (Keyhole surgery). He may also treat other conditions present in the shoulder at the time of surgery. These can include arthritis between the clavicle (collarbone) and the acromion (acromioclavicular arthritis), inflammation of the biceps tendon (biceps tendonitis), or a partial rotator cuff tear.

Rehabilitation. After surgery, your arm may be placed in a sling for a short period. This allows for early healing. As soon as your comfort allows, Prof Imam or a team member will remove the sling to begin exercising and using the arm.
Prof Imam or a team member will provide a rehabilitation program based on your needs and the findings at surgery. This will include exercises to regain the range of motion of the shoulder and strength of the arm. It typically takes 2 to 4 months to achieve complete relief of pain, but it may take up to a year, especially when the problem has been going on for a long time.

• Summary

◦ Subacromial impingement is the most common cause of shoulder pain which occurs as a result of compression of the rotator cuff muscles by superior structures (AC joint, acromion, CA ligament) leading to inflammation and development of bursitis.
◦ Diagnosis can be made on physical examination with a positive Neer and Hawkins tests, and can be supplemented with MRI studies.
◦ Treatment is a trial of nonoperative measures including NSAIDs, physical therapy and corticosteroid injections. Arthroscopic subacromial decompression with possible acromioplasty is indicated in patients who fail conservative measures.

Shoulder Impingement - Professor M Imam