Dscn0975.jpg (28401 bytes) Dscn0976.jpg (21483 bytes) Lateral view, left side

Cat information:
teres major
origin:  dorsal one third of the caudal
        border of scapula
insertion:  by a common tendon with the
        latissimus dorsi on the medial surface
        of the shaft of humerus
nerve:  subscapular (middle division)
action:  rotates arm inward, flexion of arm
        in opposition to infraspinatus, teres
        minor and the deltoids

Posterior view, left side Posterior (superficial) view of origin, right side
Anterior view of insertion, right side

Human information:
teres major
origin:  posterior surface of the inferior
       
angle of scapula on inferior third of
        scapular axillary border
insertion:  crest of lesser tubercle of
        humerus, medial to latissimus dorsi
        tendon and fused with that tendon
nerve:  lower subscapular (C5 and C6)
action:  extension, adduction, and medial
        (internal) rotation of arm

This is one of the five muscles that move the arm, but are not rotator cuff muscles.  Note that it has the same action as latissimus dorsi.  The above drawings of the origin and insertion might help visualize this information (red is the origin, blue the insertion).

COPYRIGHT 2008 by William C. Johnson II
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