You don’t typically think of the lats as being shoulder stabilizers, but the latissimus dorsi tendon has fibers that attach directly to the posterior shoulder capsule which keep the capsule taught during shoulder rotation.
The biceps long head also provides an important stabilizing function during the first 50 degrees of arm elevation and external rotation by keeping the humeral head pushed back into the glenoid.
While these “uncommon” shoulder stabilizers play important roles, the subscapularis is well known in its role as the primary dynamic stabilizer to prevent anterior/superior migration of the humeral head that can result in impingement or worse a rotator cuff tear.
My friend Eric Cressey recently touched on another important aspect of the role of the subscapularis in his blog not to long ago that may of interest to strength athletes and powerlifters.
Bill
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