What happens when you tear your rotator cuff?

Functional loss: The rotator cuff typically tears at the insertion where it attaches to the humerus bone (ball part of the ball and socket). Since it stabilizes the shoulder, a tear doesn't allow the large muscles of the shoulder (deltoids) to function correctly and indirectly causes weakness and pain. A rotator cuff tear does not heal itself and usually requires surgery to reattach the tendon to the bone.

Tearing can : Be in different forms. There are full thickness tears which mean that there is a hole in the tendon all the way through. There are also partial thickness tears where some percentage of the thickness of the tendon is injured. This can be 25%, 50%, 75% or any percentage. Sometimes these can be debilitating even if only a small percent torn. Thank you!