THE ANTERIOR RADIOULNAR REGION 



473 



The muscles of the forearm may be subdivided into groups corresponding to 

 the region they occupy. One group occupies the inner and anterior aspect of 

 the forearm, and comprises the Flexor ard Pronator muscles. Another group 

 occupies its outer side, and a third its posterior aspect. The two latter groups 

 include all the Extensor and Supinator muscles. 



RADIAL ARTERY 



JENDON OF EXTENSOR CARPI 

 RADIALIS LONGUS 



MEDIAN NERVE 



VLNAR NERVE 



FIG. 354. Transverse section through the middle of the right forearm, in the position of semipronation. 



(After Braune.) 



8. The Anterior Radioulnar Region. 



The muscles in this region are divided for convenience of description into two 

 groups or layers, superficial and deep. 



The Superficial Layer. 



Pronator teres. 

 Flexor carpi radialis. 



Palmaris longus. 

 Flexor carpi ulnaris. 



Flexor sublimis digitorum. 



These muscles take partial origin from the internal condyle of the humerus by 

 a common tendon. 



The Pronator teres (m. pronator teres) has two heads. One (caput humerale), 

 the larger and more superficial, arises from the humerus, immediately above the 

 internal condyle, from the tendon common to the origin of the other muscles; 

 and from the fascia of the forearm and the intermuscular septum between it 

 and the Flexor carpi radialis. The deep head (caput ulnare) is a thin fasciculus 



