Anatomy of provocative tests for impingement syndrome of the shoulder.

The purpose of this study was to describe the extra- and intra-articular anatomic relationships present during the Neer and Hawkins tests. Nine fresh-frozen cadaveric shoulders were positioned in the impingement position described by Neer (n = 5) or that described by Hawkins (n = 4), embedded in polyurethane, and studied with the use of a cross-sectional technique. All shoulders placed in the Neer position demonstrated soft tissue contact with the medial acromion and contact between the articular surface of the rotator cuff tendons and the anterosuperior glenoid rim. Shoulders placed in the Hawkins position demonstrated consistent contact between soft tissues and the coracoacromial ligament. In all Hawkins positioned shoulders, contact between the articular surface of the rotator cuff tendons and the anterosuperior glenoid was observed. The subscapularis tendon was deformed by the coracoid in 1 of the Hawkins positioned specimens. Although factors inherent to human subjects such as edema and muscle tone may influence the anatomy, these provocative tests for subacromial impingement appear to elicit contact consistent with impingement.