Rotator Cuff Muscles

Rotator Cuff Muscles and Bursitis.

What muscles are the rotator cuff muscles?
And why are so important?
What happens when the rotator cuff muscles are out of balance?
What is Shoulder Bursitis?

Firstly,  we look in too which 4 muscles are the rotator cuff muscles.

Subscapularis
Origin	Subscapular fossa of scapula.
Insertion	Lesser tubercle of humerus.
Action	Arm internal rotation; Stabilizes humeral head in the glenoid cavity.
Infraspinatus
Origin	Infraspinous fossa of the scapula.
Insertion	Greater tubercle of the humerus.
Action	Arm external rotation; Stabilize the humeral head in the glenoid cavity.
Teres Minor
Origin	The inferior lateral border of the scapula.
Insertion	Greater Tubercle of Humerus.
Action	Arm external rotation, arm adduction; Stabilizes humeral head in the glenoid cavity.
Supraspinatus
Origin	Supraspinous fossa of scapula.
Insertion	Greater tubercle of the humerus.
Action	Arm abduction; Stabilization of the humeral head in the glenoid cavity.

Now, that we are more aware of the rotator cuff muscles’ anatomy, we can look into their functionalities.

So, the rotator cuff muscles’ functionality is to hold the humerus bond in place in the glenoid cavity.

Furthermore, if it was not for those groups of muscles when our arm goes into abduction, the humorous head would pop out of the shoulder joint.

Indeed, for abduction, we refer to the arm movement, where the arm goes away from the body laterally.

As listed above, all those muscles originate from different areas of the scapula.

As per result, muscle as Infraspinatus and Subscapolaris are responsible for balancing the scapula along the sagittal plane.

For instance, if the Infraspinatus is overtaking in force the Subscapularis, the scapula would result in a winged position.

Consequently, this would affect other muscles that insert onto the scapula, for example, Rhomboids, Lat Dorsi etc…

Regarding the injuries, as I already mentioned in the blog post “functional test”, the rotator cuff muscles can easily be injured.

This is due to the acromion clavicular joint anatomy.

Indeed the space between the humeral head and the acromion is quite narrow and hosts what we call Bursa.

If this post is talking to you, and you are in need of a massage, book your next session by clicking here.

So, a Bursa is a soft bag, that seats between the bonds, allowing tendons to run through the joint without being exposed to pinch between bonds, and keep the bonds separated, avoiding frictions.

As per result, by putting the Bursa under repetitive stress, it tends to swallow and get inflamed.

Consequently, the tendons that run below the bursa can get squeezed, creating shoulder bursitis, or shoulder impingement.