Indications for Arthroscopic Subacromial Decompression. A Level V Evidence Clinical Guideline.

Since the introduction of acromioplasty by Neer in 1971 and arthroscopic subacromial decompression (SAD) by Ellman in 1987, the outcomes have been reported to be consistently good. Recently it was suggested that supervised physical therapy is comparable with SAD, which was contested by other studies claiming that SAD is clearly superior to nonoperative treatment. Before consideration for treatment, the diagnosis of impingement with an intact rotator cuff must be determined by clinical history, a detailed and structured clinical examination, and appropriate imaging. In favor of SAD are published long-term studies with a minimum of 10 years outlining significant functional and clinical improvement. The main factor for failure reported was workers compensation, calcific tendinopathy, and high-grade partial-thickness tears. Studies nonsupportive of SAD suffer from bias, crossover from the nonoperative group to the operative group following failure of conservative treatment, and loss of follow-up. Recently, lateral acromion resection has been suggested as a viable alternative, effectively reducing the critical shoulder angle. Following nonoperative treatment for at least 6 weeks, SAD is a viable and good surgical option for the treatment of shoulder impingement with an intact rotator cuff. Care should be taken to avoid resection of the acromioclavicular ligament. Five millimeters of lateral acromion resection is the recommended amount of resection. Patients with chronic calcific tendinitis, workers compensation, and partial-thickness tears should not be treated by SAD alone.