Q: What are the Symptoms of Subacromial Impingement Syndrome?

A: The Symptoms of Subacromial Impingement Syndrome are shoulder pain during active elevation of the arm (usually reported at the anterior or lateral side of the shoulder). The onset is more of a gradual, degenerative process rather than due to an injury or strong external force. Therefore, patients have difficulty determining the exact time of when the shoulder pain began. 

Classification of the Impingement Syndrome

•First stage:

o   Moderate pain during exercise overhead

o   No loss of strength

o   No limitation in movement

o   Involves edema and/or hemorrhage.

o   This stage most commonly occurs in patients less than 25 years of age, but can be older 

o   Frequently associated with an overuse injury.

o   Generally, at this stage the syndrome is reversible.

•Second stage:

o   Pain during Activities of Daily Living; especially during the night time

o   Loss of mobility

o   Stage II is more advanced than Stage I and tends to occur in patients 25 to 40 years of age.

o   Progressive Deterioration of the tissues of the rotator cuff

•Third stage:

o   Strong restriction in movement due to calcifications

o   Loss of muscle strength

o   Stage III occurs in patients over 40-50 years of age and

o   Frequently involves a tendon rupture or tear.

o   Mechanical Dysfunction from the culmination of fibrosis and tendinosis that has been present for many years.

Neer CS 2d. Anterior acromioplasty for the chronic impingement syndrome in the shoulder: a preliminary report. J Bone Joint Surg [Am] 1972;54:41-50.