Excessive anterior or insufficient posterior glide of the of the humeral head is noted during shoulder motions.  This syndrome may be associated with laxity of the anterior structures and stiffness or shortness of the posterior structures of the GH joint.  The subscapularis is frequently lengthened or weak and the posterior deltoid dominates over infraspinatus and teres minor muscles.  The muscles that attach further from the axis of rotation (e.g., pectoralis major, latissimus, teres major) dominate over the subscapularis. (Sahrmann, 2002)