OBLIQUE INGUINAL HERNIA. 1025 



resistance ; and these are the circumstances under which protrusions actually 

 take place. 



INGUINAL HERNIA. 



The protrusions of the viscera, or hernise, which occur in the course of 

 the inguinal canal, are named " inguinal" Of this form of the disease 

 two varieties are recognised : and they are distinguished according to the 

 part of the canal which they first enter, as well as by the position which they 

 bear with respect to the epigastric artery. Thus, when the hernia takes 

 the course of the inguinal canal from its commencement, it is named 

 oblique, because of the direction of the canal, or external, from the position 

 which its neck bears with respect to the epigastric artery. On the other 

 hand, when the protruded part, without following the length of the canal, is 

 forced at once through its termination, i. e. through the external abdominal 

 ring, the hernia is named, from its course, direct, or, from its relation to 

 the epigastric artery, internal. In these, the two principal varieties of 

 inguinal hernia, there are some modifications which will be adverted to in 

 the special notice of each. 



Oblique inguinal hernia. In the common form of this hernia the pro- 

 truded viscus carries before it a covering of peritoneum (the sac of the hernia), 

 derived from the outer fossa of that serous membrane ; and, in passing along 

 the inguinal canal to the scrotum, it is successively clothed with the cover- 

 ings given to the spermatic vessels from the abdominal parietes. The hernia 

 and its pac lie directly in front of the vessels of the spermatic cord (the intes- 

 tines and the peritoneum having the same position relatively to those vessels 

 in the abdomen) ; but, when the disease is of long standing, the vessels may 

 be found to be separated from each other,, and pressed more or less towards 

 the side or even the fore part of the sac, under the influence of the weight 

 of the tumour. The hernia does not extend below the testis, even when it 

 attains large size. That it does not is owing, doubtless, to the intimate 

 connection which the coverings of the cord have with the tunica vaginalis 

 testis. 



When the hernia does not extend beyond the inguinal canal, it is distin- 

 guished by the name bubonocele: and when it reaches the scrotum, it is com- 

 monly named from that circumstance scrotal hernia. 



There are two other varieties of oblique inguinal hernia, in which the 

 peculiarity depends on the condition of the process of peritoneum that accom- 

 panies the testis \vhen this organ is moved from the abdomen. In ordinary 

 circumstances the part of the peritoneum, connected immediately with the 

 testis, becomes separated from the general cavity of that serous membrane 

 by the obliteration of the intervening canal ; and the hernial protrusion 

 occurring after such obliteration has been completed, carries with it a dis- 

 tinct serous investment the sac. But if the hernia should be formed before 

 the process of obliteration is begun, the protruded part is then received into 

 the cavity of the tunica vagiualis testis, which serves in the place of its 

 sac. In this case the hernia is named congenital (hernia tunicse vaginalis, 

 Cooper). It is thus designated, because the condition necessary for its for- 

 mation usually exists only about the time of birth ; but the same variety of 

 the complaint is occasionally found to be first formed in the adult, obviously 

 in consequence of the tunica vagiualis remaining unclosed, still continuous 

 with the peritoneum. The congenital hernia, should it reach the scrotum, 

 passes below the testis ; and, this organ being imbedded in the protrude^ 



3 x 



