For a good long while, the 1972 JBJS article titled “Anterior Acromioplasty for the Chronic Impingement Syndrome in the Shoulder” by Charles S. Neer II completely changed the treatment approach for patients with shoulder disability. Impingement of the rotator cuff beneath the coracoacromial arch was recognized at that time as the cause of chronic shoulder disability, and complete acromionectomy and lateral acromionectomy at various levels had been advocated for the condition. However, disappointment with the results, such as postoperative deltoid weakness, stimulated Neer to publish this study, based on his experiences with patients from 1965 to1970. The paper describes relevant anatomical findings and then discusses the indications, technique, and preliminary results of anterior acromioplasty.
Neer first dissected 100 cadaveric scapulae from donors who had been in their sixth decade or older at the time of death, and he noted spurs and excrescences on the undersurface along the anterior-inferior rim of the acromion in many shoulders that also had rotator cuff derangement. Without exception, the anterior lip and undersurface of the anterior third of the acromion were involved. He concluded that this part of the acromion rubbed against the supraspinatus when the arm was abducted and caused the rotator cuff to tear over time.
Neer later resected this part of the acromion in fifty shoulders in forty-six patients. When he reexamined twenty-nine of the shoulders between nine months and five years after surgery, he found symptomatic relief in a large percentage of patients. A recent PubMed search identified 471 publications about acromioplasty, the majority of which reference this paper and 50 of which specifically mention Neer by name. Neer’s basic surgical principles are still followed, although this surgery today is performed arthroscopically.
Neer reserved this surgical procedure for patients with long-term disability from chronic bursitis and partial tears of the supraspinatus tendon, or those with complete tears of the supraspinatus associated with tears of varying degree of the adjacent rotator cuff. He emphasized that patients with incomplete tears should not have surgery until the stiffness of the shoulder resolved, and the disability had to persist for at least nine months before surgery was performed. Many patients not included in his series were suspected of having impingement but responded well to conservative treatment.
Neer’s anatomical approach to the challenge of chronic shoulder pain provides readers with photographs of cadaveric shoulders combined with drawings illustrating the pathogenesis and the surgical procedure. Neer described the results well and in a subsequent discussion concluded that “it is a rare cuff tear that cannot be repaired through this simple approach.” The paper lacked a control group and a detailed description of the rehabilitation protocol, but these shortcomings have been remedied by more recent published research.
Neer’s hypothesis that impingement caused most rotator cuff tears does not appear to have withstood the test of time, however. Arthroscopy and magnetic resonance imaging arthrography have elucidated many other conditions that cause shoulder pain that were previously misdiagnosed as impingement. Consequently, the liberal use of acromioplasty to treat “impingement” is being replaced by a trend toward making an anatomic diagnosis, such as a partial or complete tear of the rotator cuff, and performing aggressive rehabilitation prior to corrective surgery.
Lars Engebretsen, MD, PhD
JBJS Deputy Editor