THE ABDOMINAL WALLS. 91 



Landmarks for lumbar colotomy. 

 The kidneys. The spleen. 

 Aorta and iliac arteries. 



Some of the branches of the aorta : 



Coeliac axis. Superior mesenteric artery. 

 Renal arteries. Inferior mesenteric artery. 



Dissection of the Abdominal Walls. Inguinal Hernia. Umbilical Hernia. 



Make a circular incision and raise a button of skin around the umbilicus. With a narrow sharp knife, 

 open into the abdominal cavity through the umbilicus; through this opening inflate the abdominal 

 cavity enough to render the abdominal walls moderately tense, close the opening with a ligature tied 

 under the circular button. Make a median incision from the middle of the sternum to the symphysis 

 pubis, and two transverse incisions : one from a point midway between the pubis and umbilicus, to the 

 anterior superior spine of the ilium and along the crest, the other from the umbilicus in the direction of 

 the axilla, to the lower border of the pectoralis major. Beginning at the umbilicus turn the skin upward 

 from that point, and outward from the median line, and expose the superficial fascia underneath. 



The Abdominal Parietes, 425. (421-2) 



Carefully turn off the first layer of the superficial fascia, in the same manner as the skin, and expose the 

 superficial vessels and nerves. 



The superficial nerve supply of the abdomen is derived from branches of the lower intercostal, ilio-hypo- 

 gastric and ilio-inguinal nerves. Fig. 460, P. 844. (824) 



Superficial nerves: 



Lower intercostal nerves: 



Lateral cutaneous nerves of the abdomen, 845. 

 Anterior branches. Posterior branches. 

 Anterior cutaneous nerves of the abdomen, 846. 

 Last thoracic nerve, 846. (826) 



Hypogastric branch of the ilio-hypogastric, 848. (829) 

 Ilio-inguinal nerve, terminal branches, 849. (829) 

 The superficial arteries : 



From the intercostal arteries: 



Lateral cutaneous branches, 583; Fig. 362. (572) 

 From the femoral : 618. (606) 



The portion of the vessels above Poupart's ligament should be exposed ; the origin from the 

 femoral will be shown later. 



Superficial external pudic. 

 Superficial epigastric. 

 Superficial circumflex iliac. 



Cutaneous branches from the deep circumflex iliac, 613. (602) 

 Cutaneous branches from the superior epigastric, 550. (540) 

 Cutaneous branches from the deep epigastric, 613. (601) 

 The superficial veins accompany the superficial arteries. 

 Lymphatics of the abdomen and pelvis, 699-700 ; Fig. 400. (684) 

 Parietal lymphatic vessels : 



Superficial. Deep. 



Superficial parietal lymphatics, front, lateral. 

 The inguinal glands, 705. (691) 



Oblique or inguinal glands proper. 



Turn off the deep layer of the superficial fascia and expose the structures underneath. 



Read : The Muscles, 296-302. (299305) 



i. The name. 2. The shape. 3. The attachments ; origin, insertion. 

 4. The structure. 5. Nerve-supply. 6. Action. 

 The abdominal muscles, linea alba, umbilicus, 425-6. (422) 

 Obliquus externus abdominis, 428-9-30 ; Fig. 303. (424-67) 

 Origin. Insertion. 



Structure : Triangular fascia, Fig. 285; P. 365. (364) 

 External abdominal ring. 

 Poupart's ligament. Gimbernat's ligament. 



