Pectoralis minor muscle

Dscn1787.jpg (77074 bytes) Ventrolateral view, left side

Cat information:
pectoralis minor
originlateral half of the first six divisions
          of the body of the sternum and
          sometimes the xiphoid process

insertion:  ventral border of the bicipital groove
          at the proximal end of humerus
nerve:  anterior thoracic 
adducts arm

9.gif (24683 bytes) Anterior view, right side
Anterior view of origin and insertion, right side

Human information:
pectoralis minor
origin:  anterior surface of ribs 3, 4, and 5
        near the costal cartilages
insertion:  coracoid process of scapula
nerve:  medial pectoral (C8, T1)
action:  depress, protract, and inferior
        rotation of scapula

Pectoralis minor is one of the five muscles that are grouped as muscles of the scapula, or sometimes as muscles that moor the scapula.  In humans it is one of two pectoral muscles and it is smaller than pectoralis major but in the cat it is the largest of the four pectoral muscles.  The above drawing of the origin and insertion might help visualize this information (red is the origin, blue the insertion).

COPYRIGHT 2009 by William C. Johnson II