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 should er dislocation and instability Using orthographic projection, we evaluated the Hill-Sachs lesion in 30 shoulders in 27 patients with recurrent anterio r shoulder instability. This produced a clear and undistorted view of the p osterolateral notch. For orthographic imaging, the patient was placed supin e with the arm in 135 degrees of flexion and 15 degrees of internal rotatio n. 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 shall ow Hill-Sachs lesion was indicative of a greater degree of anterior instabi lity of the shoulder.