Shoulder impingement, also called subacromial pain syndrome, is irritation of the rotator cuff tendons and the bursa as they pass beneath the acromion, the bony roof of the shoulder. Reaching overhead narrows that space and pinches the tissue, which produces pain.
It is one of the most common causes of shoulder pain and often responds well to rehabilitation that restores the balance and mechanics of the rotator cuff and shoulder blade. Impingement can also be an early stage on the way to a rotator cuff tear, so it is evaluated with that in mind.
Symptoms
Common complaints include:
- Pain reaching overhead or out to the side, a 'painful arc'
- Pain sleeping on the shoulder or reaching behind the back
- Aching down the outside of the upper arm
- Weakness or pain lifting the arm
How it is diagnosed
Impingement is largely a clinical diagnosis, based on the pattern of pain and specific tests that reproduce it. X-rays show the shape of the bony arch, and an MRI or ultrasound is used when a rotator cuff tear is suspected, since that changes the plan.
Most impingement improves without surgery. Dr. Lee emphasizes a structured rotator-cuff and shoulder-blade rehabilitation program, activity modification, and, when needed, a corticosteroid injection into the subacromial space, which can both relieve pain and help confirm the diagnosis. Those that have a partial tear of the rotator cuff however should not get a corticosteroid shot, and instead may consider PRP.
Surgery is reserved for impingement that does not settle after a genuine course of rehabilitation. An arthroscopic subacromial decompression makes more room for the cuff, and any associated problem, such as a cuff tear, is addressed at the same time. First, though, Dr. Lee makes sure there is not an unrecognized cuff tear driving the symptoms.
Non-surgical treatment
Most patients improve with:
- A structured rotator-cuff and shoulder-blade strengthening program
- Activity modification to reduce provocative overhead loading
- Anti-inflammatory measures
- A subacromial corticosteroid injection, which is also diagnostic
Surgical treatment
When impingement persists despite a genuine course of rehabilitation, an arthroscopic subacromial decompression makes more room beneath the bony arch. Any associated problem, such as a cuff tear or AC arthritis, is treated at the same time.
Recovery timeline
Recovery is usually steady with rehabilitation:
- Weeks 0 to 6Structured therapy program and activity modification. Expect gradual improvement.
- Weeks 6 to 12Progressive strengthening and a graded return to overhead activity. Often patients can be cleared for most activities including sports around 6 weeks postop.
- After surgery (when needed)Early motion, then progressive strengthening over six to twelve weeks.
What patients commonly misunderstand
Two things to get right first:
- Rule out a cuff tear first. Impingement and rotator cuff tears can feel similar. Confirming whether the cuff is torn matters, because a tear changes the treatment.
- Rehabilitation usually works. The large majority of impingement settles with a targeted strengthening program. Surgery is for the minority that does not improve after a genuine rehabilitation effort.
This page is general educational content authored by Dr. Lee. It is not a substitute for individual medical advice. Every patient's case is different, book a consultation to discuss yours.