Recurrent anterior glenohumeral joint dislocation and torsion of the humerus.

Two computerized axial tomographic sections, one taken just below the coracoid process and the other about 2.5 cm proximal to the interepicondylar line, were used to determine glenoid version and humeral torsion in 19 patients with recurrent anterior glenohumeral joint dislocation and in 23 controls. Analysis of interobserver variation revealed the method to be reliable. There was no difference in glenoid version between the two groups. However, humeral torsion was greater in patients (153 degrees) than in controls (144 degrees). It appears that increased humeral torsion may predispose to glenohumeral joint dislocation.