Radiographic evaluation of the Hill-Sachs lesion in patients with recurrent anterior shoulder instability

The Hill-Sachs lesion is an important bony sign of previous anterior shoulder dislocation and instability. Using orthographic projection, we evaluated the Hill-Sachs lesion in 30 shoulders in 27 patients with recurrent anterior shoulder instability. This produced a clear and undistorted view of the posterolateral notch. For orthographic imaging, the patient was placed supine with the arm in 135° of flexion and 15° of internal rotation. The x-ray beam was angled vertically through the humeral head. The width and depth of the posterolateral notches were measured on the orthographic radiographs. The average posterolateral notch depths were 3.9 ± 0.9 mm in the dislocation group and 2.1 ± 1.0 mm in the subluxation group. A shallow Hill-Sachs lesion was indicative of a greater degree of anterior instability of the shoulder. (J Shoulder Elbow Surg 2000;9:495-7.)