Shoulder pain is "unilateral or bilateral pain of the shoulder. It is often caused by physical activities such as work or sports participation, but may also be pathologic in origin."
A careful history is essential in diagnosis. While some shoulder pain is of gradual onset, sudden onset of pain, and the patient's activity at the time (i.e., mechanism of injury) is key information.
Two-thirds of shoulder pain is due to rotator cuff lesions. Rotator cuff strengthening and stretching should be part of athletic training programs, but the specific but simple exercises are not often done, predisposing to injury.
Shoulder impingement syndrome
Shoulder impingement syndrome is "compression of the rotator cuff tendons and subacromial bursa between the humeral head and structures that make up the coracoacromial arch and the humeral tuberosities. This condition is associated with subacromial bursitis and rotator cuff (largely supraspinatus) and bicipital tendon inflammation, with or without degenerative changes in the tendon. Pain that is most severe when the arm is abducted in an arc between 40 and 120 degrees, sometimes associated with tears in the rotator cuff, is the chief symptom."
Shoulder joint tear
Injury to the labrum, the fibrous ring that holds the head of the humerus, the upper bone of the arm, in its socket (i.e., the glenoid) in the shoulder joint, can come from repetitive motion, or specific trauma such as:
- "Falling on an outstretched arm
- A direct blow to the shoulder
- A sudden pull, such as when trying to lift a heavy object
- A violent overhead reach, such as when trying to stop a fall or slide"
- Hard throwing movements
History and physical examination
In Gerber's lift-off test, the patient is asked to place the hand against the back at the level of the waist with the elbow in 90° flexion. The examiner pulls the hand to about 5–10 cm from the back while maintaining the 90° bend in the elbow. The patient is then asked to hold the position without the examiner's help. The test is considered positive if the hand cannot be lifted off the back without feeling the pain. 
Strengthening exercises with rubbed bands may help.
Several meta-analyses have addresses intra-articular injections:
- In 2009, a review of 20 trials concluded that injections with corticosteroids and oral non-steroidal anti-inflammatory agents have similar effect.
- In 2005, a review of 7 trials concluded "Subacromial injections of corticosteroids are effective for improvement for rotator cuff tendonitis up to a 9-month period. They are also probably more effective than NSAID medication."
- In 2003, the Cochrane Collaboration reviewed 26 trials and concluded "there is little overall evidence to guide treatment".
Extracorporeal shock wave therapy
Extracorporeal shock wave therapy (ESWT) may help calcific tendonitis of the shoulder.
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- Shoulder Joint Tear (Glenoid Labrum Tear), American Academy of Orthopedic Surgeons
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