Describe the rotator cuff: <--this is a picture showing the muscles
The rotator cuff is comprised of four muscles attached the the scapula. The actions are best described when compared to pitching a baseball...
subscapularis (wind up for a pitch)
origin: subscapular fossa of the scapula
insertion: lesser tubercle of the humerus
action: medially rotates arm
supraspinatus (start to execute the pitch)
origin: supraspinous fossa of the scapula
insertion: greater tubercle of the humerus
action: abducts arm
teres minor (help to slow down the pitching arm upon completion of the pitch)
origin: upper dorsal lateral border of the scapula (superior to teres major origin)
insertion: greater tubercle of the humerus
infraspinatus (help to slow down the pitching arm upon completion of the pitch)
origin: infraspinous fossa of the scapula
insertion: greater tubercle of the humerus
action: adducts and laterally rotates arm
Collectively, these four muscles stabilize the glenohumeral joint.
(For more information - read the clinical view on page 360 of the textbook, McKinley & O'Loughlin, Human Anatomy, 2nd edition)
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment