According to NASM’s Essentials of Corrective Exercise Training the dynamic stabilizers of the “glenohumeral joint is dependent on the musculature that surrounds the joint, including the rotator cuff and scapular stabilizers.”
The key muscles associated with the shoulder are:
4. Teres major and minor
6. Pectoralis major and minor
7. Latissimus dorsi
10. Levator scapulae
The static stabilizers “include such structures as the glenoid labrum and the glenohumeral joint capsule consisting of two major ligaments, the middle and inferior glenohumeral ligaments.
The scientific sources the NASM utilize in support of what is written in their text are:
1. Terry G, Chopp T, Functional anatomy of the shoulder. J Athl Train 2000:35:248-55
2. Moore KL. Clinically Oriented Anatomy, 3rd ed. Baltimore, MD; Williams & Wilkins; 1992.
It’s important to understand static stability of the glenohumeral joint as opposed to dynamic stability of the glenohumeral joint.
Static stability of the glenohumeral joint occurs when one is “standing at rest with the arms at the side and the head of the humerus remains stable against the glenoid fossa.”
This is important as an individual’s posture can have an effect on static stability of the glenohumeral joint.
Thank you for such a thought-provoking question.
good to be of your opinion. I respect opinions. What does the science say?
The question asked what are the primary static stabilizers where it didn’t address dislocations
“Teaching The Science Behind The Movement”
I am of the opinion that it would be faulty to assume that only muscles such as the rotator cuff muscles and the pectorals are responsible for stabilization of the glenohumeral joint. Ligaments are also involved.
As an example, if a person dislocated their shoulder, the coracohumeral, coracoacromial or the capsular ligaments might be compromised. If this happens glenohumeral joint stability is compromised.