The shoulder can lose its normal retaining structures that prevent the abnormal subluxation of the humerus and the glenoid. The shoulder joint is surrounded by a capsule which is reinforced by a thickened area known as a ligament. Stretching or tearing of these reinforcement structures allow for abnormal slippage of the arm bone (humerus) and the shoulder cup (glenoid).

Symptoms:

Patients will experience a feeling that the shoulder “is coming out of its joint” with activity. Sometimes, overhead activities such as pitching a baseball or serving in tennis will cause the arm to go numb. This is known as “dead arm syndrome.”

Diagnosis:

Evaluation usually involves a provocative physical exam and a specialized study such as MRI or CT arthrogram. An arthrogram is a test which involves injecting contrast material (dye) into a joint to better outline the internal structures. This test helps differentiate between normal anatomy and areas of injury.

Treatment:

This condition may respond to an exercise program but recurrent episodes and non-responsive joints may require surgical treatment.

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