It’s impossible to say for certain in the absence of randomized controlled trials. However, in patients whose impingement symptoms don’t improve after 3 to 6 months, arthroscopic subacromial decompression (ASD) is associated with modest (about 10%) long-term improvement in pain and function compared with open acromioplasty or baseline (strength of recommendation [SOR]: B, cohort studies).
Patients older than 57 years may do better with surgery than physical therapy (SOR: B, single cohort study).
EVIDENCE SUMMARY
Six cohort studies found that patients who underwent ASD for subacromial impingement had improved pain and function scores at 4.5 to 12 years after surgery (TABLE1-7). Weaknesses of the overall data set include use of heterogeneous outcome measures across studies, lack of sham surgical controls, and lack of blinding.
ASD improves pain and function slightly more than other treatments
One prospective and one retrospective cohort trial compared ASD with another intervention. In the prospective trial, ASD was associated with a 10% better combined pain and function score than open acromioplasty at 12 years.1 In the retrospective trial, ASD was also associated with a 10% better combined pain and function score than prolonged physical therapy in patients older than 57 years (the median age of study participants) but not patients younger than 57 years.2