RADIOGRAPHIC DIAGNOSIS OF ACROMIOCLAVICULAR JOINT SEPARATION WITHOUT WEIGHT-BEARING - IMPORTANCE OF INTERNAL-ROTATION OF THE ARM

In recent years, we have diagnosed grade III separations of the acromi oclavicular joint in three patients on the basis of findings on antero posterior radiographs obtained with the patient upright with the arm i n internal rotation without weights. Each of the patients came to the emergency department with shoulder pain but with no clinical evidence of acromioclavicular separation. In each case, the anteroposterior vie w obtained with the arm in internal rotation was diagnostic. To clarif y why this separation occurs with internal rotation, we dissected cada vers and correlated surgical and radiographic findings.