Rotator Cuff

The rotator cuff is a group of four muscles and their tendons that act to stabilize the shoulder.


The rotator cuff muscles are important in shoulder movements and in maintaining glenohumeral joint (shoulder joint) stability.[2] These muscles arise from the scapula and connect to the head of the humerus, forming a cuff at the shoulder joint. They hold the head of the humerus in the small and shallow glenoid fossa of the scapula. The glenohumeral joint has been analogously described as a golf ball (head of the humerus) sitting on a golf tee (glenoid fossa).[3]

During abduction of the arm, moving it outward and away from the trunk, the rotator cuff compresses the glenohumeral joint, a term known as concavity compression, in order to allow the large deltoid muscle to further elevate the arm. In other words, without the rotator cuff, the humeral head would ride up partially out of the glenoid fossa, lessening the efficiency of the deltoid muscle. The anterior and posterior directions of the glenoid fossa are more susceptible to shear force perturbations as the glenoid fossa is not as deep relative to the superior and inferior directions. The rotator cuff’s contributions to concavity compression and stability vary according to their stiffness and the direction of the force they apply upon the joint.



Causes & Treatment

Rotator cuff pain and dysfunction is commonly caused by the subscapularis not doing its job effectively, and resultant compensation by surrounding anatomy. Through Active Release Techniques, Graston and sometimes manipulation, our objective is to correct the biomechanics of the shoulder joint. This is commonly accomplised by restoring proper function to the subscapularis. The subscapularis works to keep the humeral head back and down (posterior and inferior) in the ball and socket joint of the shoulder. When there is damage and dysfunction of the subscapularis, the humeral head goes up and forward (superior and anterior), this leads to impingement of the supraspinatis tendon as the arm is raised.

This is followed by a flexibility and strength and stabilization program.

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Tendinosis versus Tendinitis

Active Release Techniques

Graston Technique