Subacromial decompression is an operation on your shoulder that treats a shoulder impingement condition, where you feel pain when you raise your arm. It’s usually done through keyhole surgery (arthroscopy). You might also hear subacromial decompression referred to as ‘acromioplasty’.
What is shoulder impingement?
Shoulder impingement is a common type of shoulder pain. You have a group of muscles called the ‘rotator cuff’ which surround and support your shoulder. The tendons for these muscles lie in a narrow space between the top of your arm bone and the bone at the top of your shoulder blade. Shoulder impingement is the name given to the pain you feel if the tendons within this space become damaged. Doctors aren’t certain why this happens, but it may be due to several causes, perhaps acting together. These may include:
your tendons becoming swollen or torn from overuse (for instance, doing sports) or ‘wear and tear’ as you get older the shape of the bone at the top of your shoulder blade (the acromion), causing it to rub against your tendons getting bony growths (spurs) on the acromion as you get older
If you have shoulder impingement, you’ll feel pain when you raise your arm. You may have some muscle wasting of the affected arm, and your arm movements may be restricted.
How is subacromial decompression done?
Subacromial decompression is done as a keyhole procedure using an arthroscope. During decompression surgery, a surgeon removes bone tissue to increase the subacromial space, located between the shoulder’s ball-and-socket and the bone above it, called the acromion.
Decompression surgery can involve one or both of these procedures:
Shaving down the acromion bone in a process called acromioplasty. Shaving down the acromion underside relieves shoulder impingement symptoms by reducing pressure on the rotator cuff and bursa.
Removing bone spurs (called osteophytes) that have developed on the shoulder’s bones. These bone spurs can rub uncomfortably against the rotator cuff and the subacromial bursa.