Does a positive neer impingement sign reflect rotator cuff contact with the acromion?

BACKGROUND One possible cause of shoulder pain is rotator cuff contact with the superior glenoid (cuff-glenoid contact) with the arm in flexion, as occurs during a Neer impingement sign. It has been assumed that the pain with a Neer impingement sign on physical examination of the shoulder was secondary to the rotator cuff making contact with the anterior and lateral acromion. QUESTIONS/PURPOSES We determined if the arm position where pain occurs with a Neer impingement sign would correlate with the position where the rotator cuff made contact with the superior glenoid, as determined by arthroscopic evaluation. PATIENTS AND METHODS We prospectively studied 398 consecutive patients with a positive Neer impingement sign during office examination and used a handheld goniometer to measure (in degrees of flexion) the arm position in which impingement pain occurred. During subsequent arthroscopy, the arm was moved into a similar position, and we measured the arm's position in flexion at the point the rotator cuff made contact with the superior glenoid using a handheld goniometer. We compared the degrees of flexion at which pain occurred preoperatively and at which there was cuff-glenoid contact. RESULTS Among the 398 patients, 302 (76%) had arthroscopically documented cuff-glenoid contact, whereas 96 did not. For the 302 patients with a positive Neer sign preoperatively and with arthroscopically documented cuff-glenoid contact, the average preoperative impingement pain position was 120.1°±26.7°, similar to that of the average intraoperative cuff-glenoid contact position of 120.6°±14.7°. CONCLUSIONS Our data suggest pain associated with a positive Neer sign more often relates to contact of the rotator cuff with the superior glenoid than to contact between the rotator cuff and acromion. LEVEL OF EVIDENCE Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.