Usually the echogenicity compared to the deltoid muscle is homogeneous intensified without dorsal echo extinction. Variability with reduced or intensified  echo has also been found in healthy tendons. Bilateral comparison is very helpful when distinguishing and setting boundaries between physiological variants and a possible pathological finding. Degenerative changes at the rotator cuff often are found on both sides of the body.  Consequently, unilateral differences rather point to a pathological source and bilateral changes rather to a physiological variation. 
The geometry of the bony articulation is inherently unstable. The rotator cuff is a dynamic stabilizer and the capsulolabral tissues are considered static stabilizers. With the arm at 90 degrees abduction, the anterior band of the inferior gleno-humeral ligament complex is the primary static stabilizer to anterior translation. The middle (MGHL) resists anterior translation at 45 degrees of abduction. The superior (SGHL) resists inferior translation with the arm at one's side.
O'Brien et al. describe the functional anatomy of the inferior gleno-humeral complex based on a series of cadaveric dissections. They note that its orientation and design support the functional concept of this single structure as an important anterior and posterior stabilizer of the shoulder joint. The Burra paper is a review of acute upper extremity instability in athletes.
Glenohumeral ligaments (superior, middle and inferior) – Consists of three bands, which runs with the joint capsule from the glenoid fossa to the anatomical neck of the humerus. They act to stabilise the anterior aspect of the joint.