DISSECTION OF THE INGUINAL REGION. 285 



As the vessel extends backwards it gives lateral offsets, which and anasto- 

 supply the neighbouring muscles, and communicate on the one side m 

 with the ilio-lumbar, and on the other with the gluteal artery. 



The deep curcwmjlex iliac vein is formed by the junction of two Circumflex 

 collateral branches, and crosses the external iliac artery nearly an iliac vein ' 

 inch above Poupart's ligament, to open into the external iliac vein. 



SECTION II. 



HERNIA OF THE ABDOMEN. 



The lower part of the abdominal wall, which has been reserved inguinal 

 on the left side of the body, should now be dissected for inguinal 

 hernia. 



Dissection. The integuments and the aponeurosis of the external The dissec- 

 oblique having already been reflected, the necessary dissection of 

 the inguinal region will be completed by raising the internal oblique 

 muscle as in fig. 106. 



To raise the internal oblique muscle, let one incision be made across Reflect 

 the fleshy fibres from the iliac crest towards the linea alba ; and 

 after the depth of the muscle has been ascertained by the layer of 

 areolar and fatty tissue beneath it, let the lowest fibres be carefully 

 cut through at their attachment to Poupart's ligament. By lifting 

 up the muscle cautiously, the student will be able to separate it 

 from the subjacent transversalis so that it may be turned inwards 

 on the abdomen. The separation of the two muscles just mentioned 

 is often difficult in consequence of their lowest fibres being blended 

 together, but a branch of the deep circumflex iliac artery serves as a 

 guide to the intermuscular interval. 



The creinaster muscle is next to be divided along the cord, and Cut the 

 to be reflected to the sides. Let the dissector then clean the surface cremaster - 

 of the transversalis muscle, without displacing its lower arched H^^- parts 

 border, and define with care the conjoined tendon of it and the 

 internal oblique to show its exact extent. The transversalis fascia 

 and the spermatic cord should also be nicely cleaned. 



Crossing the interval below the border of the transversalis muscle show the 

 are the deep epigastric vessels, which lie close to the inner side of the 

 internal abdominal ring, but beneath the transversalis fascia. A 

 small piece of the fascia may be cut out to show the vessels. 



INGUINAL HERNIA. A protrusion of intestine or other organ Situation 

 through the lower portion of the abdominal wall near Poupart's 

 ligament (answering to the inguinal region) is named an inguinal 

 hernia. The escape of the intestine in this region is favoured by Predis- 

 the deficiencies in the muscular strata, by the passage of the sper- 

 rnatic cord through the abdominal parietes and by the existence of 

 fossae on the inner surface of the wall. 



The gut in leaving the abdomen either passes through the internal Course it 

 abdominal ring with the cord, or is projected through the part of follows - 



