1018 SURGICAL ANATOMY OF HERNIJE. 



tion, the surgeon instructed by the case alluded to, and by other examples 

 of the same arrangement of the arteries which have since been observed, 

 might at once, under the guidance of the pulsation, or of the effect of 

 pressure in controlling the circulation through the aneurism, divide the 

 covering of areolar tissue over the second part of the artery, and tie it 

 likewise. 



II. SURGICAL ANATOMY OF THE PARTS CONCERNED IN 

 CERTAIN ABDOMINAL HERNIA. 



Besides the surgical anatomy of the principal arteries, certain parts of 

 the walls of the abomen and pelvis are to be now considered with refer- 

 ence to surgical operations in which the viscera of those cavities are from 

 time to time concerned. 



The walls of the abdomen, when in a healthy state, unaffected by injury, 

 disease, or malformation, retain the viscera within the cavity under all 

 circumstances ; but where certain natural openings exist for the passage of 

 blood-vessels, protrusions of the viscera, constituting the disease named 

 " hernia" or " rupture " are liable to occur under the influence of the com- 

 pression to which the organs are subjected during the production of efforts. 

 For the replacement of the viscus so protruded, an accurate acquaintance 

 with the structure of the part through which the protrusion takes place is 

 required by the surgeon ; and, on this account, an examination of the seat 

 of the hernia as a surgical region becomes necessary. 



Two of the openings by which hernise escape from the abdomen are 

 situate close together at the groin. One is the canal in the lower part of 

 the broad abdominal muscles, which gives passage in the male to the duct 

 and vessels of the testis (spermatic cord), and in the female to the round 

 ligament of the womb. The second opening exists at the inner side of the 

 large femoral blood-vessels. 



Hernial protrusions are likewise found to escape at the umbilicus, in 

 the course of the blood-vessels which occupy that opening in the foetus, or 

 in the immediate neighbourhood of the opening ; and at the thyroid foramen, 

 where the obturator vessels and nerve pass downwards to the adductor 

 muscles of the thigh. According to the situation they occupy these hernke 

 are named respectively inguinal, femoral, umbilical, and obturator. They 

 will now be separately noticed ; but, inasmuch as the structure of the parts 

 connected with the umbilical and obturator hernias is by no means intricate, 

 and as, moreover, it is noticed with sufficient detail in text-books of prac- 

 tical surgery, it will be unnecessary to refer farther in this work to those 

 forms of hernia. 



OF THE PARTS CONCERNED IN INGUINAL HERNIA. 



The inguinal hernia, it has been stated above, follows the course of the 

 spermatic cord from the cavity of the abdomen. We shall therefore, before 

 adverting to the hernia! protrusions, examine the structure of the abdominal 

 walls in the neighbourhood of the canal in which the cord is placed ; and 

 for this purpose it will be supposed that the constituents of those walls are 

 successively laid bare and everted to such an extent as would be permitted 

 by two incisions made through them, and reaching, one along the linea 

 alba for the length of three or four inches from the pubes, the other, from 

 the upper end of the vertical incision outwards to the superior spine of the 

 hip-bone. 



The superficial fascia (p. 257) is connected along the fold of the groin 



