466 



THE MUSCLES AND FASCIA. 



d, ^ ( Flexor profundus digitorum. 

 % >-> { Flexor longus pollicis. 

 ^ >_} (^Pronator quadratus. 



Radial Region. 



Supinator longus. 



Extensor carpi radialis longior. 



Extensor carpi radialis brevior. 



Posterior Radio-ulnar Region. 



li f Extensor communis digitorum. 

 J Extensor minimi digiti. 

 * J Extensor carpi ulnaris. 

 (^Anconeus. 

 ^ Supinator brevis. 



^ Extensor ossis metacarpi pollicis. 

 Extensor brevis pollicis. 



* 





OF THE HAND. 

 Radial Region. 

 Abductor pollicis. 

 Flexor ossis metacarpi pollicis (Opponens 



pollicis). 



Flexor brevis pollicis. 

 Adductor pollicis. 



Ulnar Region. 

 Palmaris brevis. 

 Abductor minimi digiti. 

 Flexor brevis minimi digiti. 

 Flexor ossis metacarpi minimi digiti 

 (Opponens minimi digiti). 



Palmar Region. 



Lumbricales. 



Extensor longus pollicis. Interossei palmares. 



Extensor indicis. Interossei dorsales. 



Dissection of Pectoral Region and Axilla (Fig. 301 ). The arm being drawn away from the 

 side nearly at right angles with the trunk, and rotated outward, make a vertical incision through 



the integument in the median line of the 

 chest, from the upper to the lower part of 

 the sternum ; a second incision along the 

 lower border of the Pectoral muscle, from 

 the ensiform cartilage to the inner side of 

 the axilla; a third, from the sternum 

 along the clavicle, as far as its centre ; 

 and a fourth, from the middle of the 

 clavicle obliquely downward, along the 

 interspace between the Pectoral and Del- 

 toid muscles, as low as the fold of the 

 armpit. The flap of integument is then 

 to be dissected off in the direction indi- 

 cated in the figure, but not entirely 

 removed, as it should be replaced on com- 

 pleting the dissection. If a transverse 

 incision is now made from the lower end 

 of the sternum to the side of the chest, 

 as far as the posterior fold of the armpit, 

 and the integument reflected outward, 

 the axillary space will be more completely 

 exposed. 



Fasciae of the Thorax. 

 The superficial fascia of the 

 thoracic region is a loose cellulo- 

 fibrous layer enclosing masses of 

 fat in its spaces. It is continu- 

 ous with the superficial fascia of 

 the neck and upper extremity 

 above, and of the abdomen below. 

 Opposite the mamma, it divides into 

 two layers, one of which passes in 



3. Dissection of 

 Shoulder and Arm. 



1. Dissection of 

 Pectoral Region 

 and Axilla. 



2. Bend of Elbow. 



4- Forearm. 



Palm of Hand. 



FIG. 301. Dissection of upper extremity. 



front, the other behind that gland ; and from both of these layers numerous septa 

 pass into its substance, supporting its various lobes : from the anterior layer fibrous 

 processes pass forward to the integument and nipple. These processes were called 

 by Sir A. Cooper the ligamenta suspensoria, from the support they afford to the 

 gland in this situation. 



The deep fascia of tbe thoracic region is a thin aponeurotic lamina, covering 

 the surface of the great Pectoral muscle, and sending numerous prolongations 



