9.11.96 dr dodson...

[diagram of forearm see notes]
           
		-------------
                \     |     /
                \     |     /    
                \     |     /
                \     |     /
		\     |     /
                 \    |    / scapula
                  \   |   / 
                   -------                  triceps goes from olecranon
                     ----                   to caudal scapula and proximal
                     \   \                  caudal humerus
		      \   \ humerus
		       \   \
                        \   \     ___
                         \   \   /   / olecranon
                          \   -- \  /
                           \    ) //
                            ---- //
                             --- /
                            /   / ulna
                           /   / 
remember, muscles work by contraction, and only have any effect when they 
cross a joint. muscles don't attach to two ends of the same bone. Also, 
muscle has an effect on any joint it crosses.

triceps - runs across elbow and shoulder joints. can extend elbow and 
flex shoulder.

[line and circle drawing illustrating principles of levers and pivots - 
see notes.]

	/
       /
      /
     o
      \
       \
        \
         \
          \ / 
           o
          /
         /
        /


[drawing of scapula w/supraspinatus, infraspinatus (both inserting on 
greater tubercle of humerus) and the subscapularis]

The supraspinatus and infraspinatus are sometimes described as active 
ligaments; they don't flex or extend a joint; they offer support to hold 
the greater tubercle into the shoulder joint. They are also part of the 
rotator cuff. 

Teres minor acts similarly to suprasp.and infrasp. - mainly vestigial, 
doesn't do much. Maybe can flex a little.

----

[drew some complex diagrams w/multicolored chalk. impossible to follow 
with black pen. will have to go over miller's for digital/carpal 
flexors/extensors.]

Horses/cows have no supinators.

Supinator is opposed by pronator teres, which originates medially, while 
the supinator originates laterally.  Pronator quadratis is an interosseus 
muscle, between bones - very deep muscle which runs the shortest distance 
between the radius and ulna. basically functions to hold them together.

------now we will consider the flexor muscles. (!?)-

------

[see diagram in notes....]

superficial digital flexor inserts on base of P2
deep digital flexor passes around s.d.f. tendon and inserts on base of 
P3.

complex architecture for deep digital flexor. has three heads. at level 
of carpus easy to distinguish by following tendons back to muscle 
bellies.

Minor set of muscles called "interosseus muscles"
There is one associated w/each metacarpal muscle. They come down and 
tendons insert on the base of each proximal phalanx. The muscles lie on 
the back of each metacarpal - flexes metacarpal/phalangeal joint. in 
humans, give fleshiness to palm of hand. 

note only a single set of extensors, but multiple flexors.