PECTORAL REGION 5 



can at once put his finger on any given point whatever the 

 position of the limb. 



Reflection of Skin. Incisions (i) Along the middle line of the body 

 from the upper margin of the manubrium sterni to the tip of the xiphoid 

 process ; (2) from the lower end of this vertical incision transversely 

 round the lateral border of the body ; (3) from the upper extremity 

 of the primary incision laterally along the clavicle to the extremity of the 

 acromion process ; (4) from the lower end of the vertical and medial incision 

 (i.e. tip of the xiphoid process) obliquely upwards and laterally, along 

 the anterior fold of the axilla, to the point at which this joins the upper 

 arm. Then down the arm for two and a half or three inches. 



Two triangular flaps of skin are marked out by these incisions, and 

 these are now to be raised from the panniculus acliposus. But, before this 

 is done, encircle the areola and nipple with the knife and leave the 

 skin covering them undisturbed. 



Panniculus Adiposus (Superficial Fascia). The fatty layer 

 which is now exposed is termed the panniculus adiposus 

 or superficial fascia. It constitutes the cushion upon which 

 the skin rests, rounds off the angularities of the body, and 

 varies in thickness according to the obesity of the subject. 

 It constitutes the bed in which the cutaneous vessels and 

 nerves ramify before they enter the skin. It is separated 

 from the muscles by a tough, but thin, layer of fibrous 

 tissue, devoid of fat, which forms another investment for 

 the body ; this aponeurotic membrane receives the name 

 of the deep fascia ; it can be readily demonstrated by making 

 an incision in the superficial fascia, and raising a small 

 portion of it. 



The superficial fascia presents here, as elsewhere, the 

 usual characters, but, as a rule, the fat is not so plentiful. 

 As it descends over the clavicle to the upper part of the 

 thorax and summit of the shoulder, it has, in most cases, a 

 faintly ruddy striated appearance. Should this not at first 

 be apparent, the removal of some of the superficial fat will 

 render it visible. This appearance is .due to the presence 

 of a number of sparse scattered muscular fasciculi which 

 stream down over the clavicle, to obtain attachment in the 

 panniculus adiposus over the pectoralis major and deltoid 

 muscles. In the neck they form a thin, cutaneous, fleshy 

 stratum, called the platysma myoides. The superficial fascia 

 in this region is also specialised by the development of the 

 mamma in its substance. It should now be dissected, with the 

 view of exposing the mamma as well as the cutaneous vessels 

 and nerves which make it their bed before entering the skin. 



i la 



