1410 SUKFACE AND SUKGICAL ANATOMY. 



avoid the round ligament of the liver. If, in closing a median supra-umbilica 

 laparotomy wound, the surgeon merely sutures the edges of the stretched line* 

 alba without opening into the rectal sheaths, a hernia may result. To ensur< 

 against it the medial borders of the recti are exposed by opening into thei: 

 sheaths along each edge of the wound. In closing the wound, the deepes 

 suture (continuous) includes on each side the posterior layer of the rectal sheatl 

 along with the split linea alba, the transversalis fascia and the peritoneum. Thi: 

 gives a substantial " first line of defence." The next suture takes up some of th< 

 fibres of the medial edges of the recti, along with the anterior layer of their sheaths 

 The skin is sutured separately. By the above procedure the edges of the recti an 

 brought into actual contact and a double-layered linea alba is fashioned, one laye: 

 behind the margins of the recti and the other in front of them. 



Below the umbilicus the medial edges of the recti are practically in contact, s< 

 that an incision between them opens into the rectal sheath on both sides. 



The nearer the opening into the abdomen approaches the symphysis pubig 

 the more likely is the bladder to be encountered ; this applies more especially ii 

 children in whom the bladder extends higher up out of the pelvis. Before opening 

 the abdomen, therefore, by a low median incision, the bladder should be emptied 

 in supra-pubic cystotomy, on the other hand, it is intentionally filled so as t< 

 elevate the peritoneum (superior false ligament of the bladder) well above thi 

 symphysis. Below this peritoneal layer is the space of Eetzius, occupied by a pat 

 of extra-peritoneal fat which must be separated by blunt dissection before th< 

 bladder wall is actually exposed. In opening the bladder the pre-vesical veins 

 which ramify on its surface, are avoided as far as possible. Above the pubes th< 

 fascia transversalis recedes somewhat from the posterior surface of the recti, leaving 

 behind it a cellular interval which must not be mistaken for the space of Eetzius. 



If a transverse incision is added to the inferior end of a supra-umbilical mediai 

 incision, free access may be obtained to the hypochondriac as well as to the epi 

 gastric region. Before dividing the fibres of the rectus, however, the anterio 

 layer of the sheath is stitched to them to prevent their retraction. In dividing thi 

 posterior layer of its sheath the terminal portions of the ninth and tenth inter 

 costal nerves need not be injured as they run in a transverse direction. 



Incisions through the Recti. In opening the abdomen by longitudina 

 incisions through the recti, the superior epigastric artery will be encountered abov< 

 the umbilicus, and the inferior epigastric below it. The nearer the opening 

 approaches the lateral border of the rectus, the more will its nerve-supply b< 

 injured. Above the level of the umbilicus, the posterior layer of the rectal sheath i 

 well developed ; and in closing the wound it is included in the same suture as th< 

 transversalis fascia and the peritoneum, the three together forming a most efficien 

 "first line of defence." The higher up and further lateral the incision is mad' 

 through the rectus, the more will the posterior layer of the sheath be found to b 

 made up of transverse muscular fibres prolonged inwards from the transversu 

 abdominis muscle. Below the level of the umbilicus, the posterior layer of th< 

 rectal sheath is much thinner, and where it ceases, namely, about midway betweei 

 the umbilicus and the pubes, it constitutes what is known as the linea semicirculari 

 (semilunar fold of Douglas). Below this level, therefore, the " deep closure " of ; 

 laparotomy wound through the rectus is less secure than is the case at a highe 

 level. It is all the more important, therefore, to see that the edges of the anterio 

 layer of the sheath are accurately sutured. 



Incisions Lateral to the Rectus. Longitudinal incisions lateral and paralle 

 to the lateral border of the rectus are as far as possible to be avoided, firstly 

 because they divide the motor nerves, and, secondly, because the abdominal wall i 

 almost entirely aponeurotic, and, therefore, a hernia is liable to result. 



Incisions lateral to the rectus, above the level of the umbilicus, are general!; 

 made more or less parallel to the costal margin. Such incisions give excellen 

 access to the gall-bladder and bile-ducts. The fibres of the external obliqu* 

 muscles are divided transversely; but, fortunately, those of the internal obliqui 

 and transversus muscles may be divided more or less parallel to the fibres. Th 

 abdominal portions of the eighth, ninth, and tenth thoracic nerves which course 



