Glenopolar angle

The glenopolar angle (GPA) is a measure for the rotational malalignment of the glenoid about an anteroposterior (front-to-back) axis perpendicular to the scapular plane. The glenopolar angle (GPA) is a measure for the rotational malalignment of the glenoid about an anteroposterior (front-to-back) axis perpendicular to the scapular plane. The glenopolar angle is defined as the angle between the line connecting the most cranial with the most caudal point of the glenoid cavity and the line connecting the most cranial of the glenoid cavity with the most caudal point of the scapular body.