The Subscapularis is 1 of the 4 rotator cuff muscles, that together have a role of keeping the head of the Humerus within the Glenoid Cavity. The Subscapularis is actually the LARGEST and most POWERFUL of the 4 rotator cuff (Keating JF, JBJB, BR.. 1993).
This muscle originates on the subscapular fossa of the scapula and inserts onto the lesser tuberosity of the humerus, which creates movement at the shoulder/gleno-humeral joint into internal rotation and horizontal adduction.
The tightness of the Subscapularis is often the culprit of limited external rotation as and may result in shoulder impingement. This is often due to the modern lifestyle that many of us live in with our shoulders in an internally rotated position while working at a computer or driving for hours at a time.
To properly release this tissue:
-Start in a sidelying position and allow the scapula/shoulder blade to abduct/protract.
-First you may need to feel around with your fingers to find the area’s of restriction or trigger points within this muscle.
-Once you have found these go ahead and tack it down using a lacrosse ball while the Subscapularis is in a shortened position. You will then take this muscle through its range of motion by going into external rotation.
-You can repeat for a couple minutes or until you feel as if the tissue has released.
To make sure if this is effective always do a test-retest and see if your shoulder external rotation has improved.
“Shoulder impingement in tennis/raquetballplayers treated with subscapularis myofascial treatments” by: Reuben Ingber showed that trigger point and therapeuic stretching of the Subscapularis has shown to reduce shoulder impingement.