1048 



THE SURGICAL ANATOMY OF HERNIA. 



obliquely upward and inward to the umbilicus. This is covered by a fold of peri- 

 toneum, which is known as the plica hypogastrica. To either side of these three 

 cords is the deep epigastric artery, which ascends obliquely upward and inward 

 from a point midway between the symphysis pubis and the anterior superior spine 

 of the ilium to the semilunar fold of Douglas, in front of which it disappears. It 

 is covered by a fold of peritoneum, which is known as the plica epigastrica. Be- 

 tween these raised folds are depressions of the peritoneum, constituting so-called 

 fossae. The most internal, between the plica urachi and the plica hypogastrica, is 

 known as the internal inguinal fossa (fovea supravesicalis). The middle one is 

 situated between the plica hypogastrica and the plica epigastrica, and is termed the 

 middle inguinal fossa (fovea inguinalis mesialis). The external one is external to 



M. iliacus. 



External 

 inguinal 

 fossa. 



External 

 iliac 

 artery. 



External 

 iliac 

 vein. 



Internal inguinal 

 fossa. 



FIG. 582. Posterior view of the anterior abdominal wall in its lower half, 

 the various cords are shining through. (After Joessel.) 



Femoral 

 -fossa. 

 Superior vesical 



artery. 

 Middle inguinal 

 fossa. 



The peritoneum is in place, and 



the plica epigastrica, and is known as the external inguinal fossa (fovea inguinalis 

 lateralis). Occasionally the deep epigastric artery corresponds in position to the 

 obliterated hypogastric artery, and then there is but one fold on each side of the 

 middle line, and the two external fossae are merged into one. In the usual con- 

 dition of the parts the floor of the external inguinal fossa corresponds to the 

 internal abdominal ring, and into this fossa an oblique inguinal hernia descends. 

 To the inner side of the plica epigastrica are the two internal fossae, and through 

 either of ^these a direct hernia may descend, as will be explained in the sequel 

 (page 1052). The whole of this space, that is to say, the space between the deep 

 epigastric artery, the margin of the Rectus and Poupart's ligament, is commonly 

 known as Hesselbaclis triangle. These three depressions or fossae are situated 

 above the level of Poupart's ligament, and in addition to them is another below 

 the ligament, corresponding to the position of the femoral ring, and into which a 

 femoral hernia descends. 



