Lateral view, left side

Cat information:
brachialis
origin:  lateral surface of humerus
insertion:  lateral surface of ulna just
        distal to the semilunar notch
nerve:  musculocutaneous
action:  flexion of forearm

Anterior view, right side Anterior view of origin, right side
Anterior view of insertion, right side

Human information:
brachialis
origin:  distal half of the anterior surface
        of humerus
insertion:  ulnar tuberosity and coronoid process
        of ulna
nerve:  musculocutaneous (C5-C6)
action:  flexion of forearm (elbow)

The above drawings of the origin and insertion might help visualize this information (red is the origin, blue the insertion).  Note that since it attaches to the ulna and not the radius, it does not cause pronation or supination.

COPYRIGHT 2008 by William C. Johnson II
ALL RIGHTS RESERVED!