Showing posts with label Arm Movements. Show all posts
Showing posts with label Arm Movements. Show all posts

Monday, April 23, 2018

Rotator Cuff

  Patients are sometimes confused about this, and wrongly think of it as part of their bones. 
But the rotator cuff consists of four MUSCLES that attach from the front, back, and side of the shoulder blade, and grip the head of the humerus (the bone in the upper arm) like a hand would grip a baseball.
These muscles stabilize the humeral head, or “knob” at the upper end of the bone, near the shoulder. They also act on the humerus to cause different movements, such as when we lift our arm out and up (abduction), turn our arm in (internal rotation) or out (external rotation).
The tendons attaching these muscles to bones act as mechanical “blockers” to excessive movements, helping to keep movements of the arm at the shoulder within normal range.
If the arm is taken beyond these normal limits of movement, tears in the tendons or muscles of the rotator cuff often happen.