1030 SURGICAL ANATOMY OF HERNIJE. 



size, the obliquity of the inguinal canal no longer remains, the internal 

 ring being enlarged and brought inwards opposite the external one, while 

 at the same time the epigastric artery, borne inwards by the hernia, curves 

 along the inner side of the sac. Under this change, the oblique hernia 

 assumes the appearance of one primarily direct. 



Operations for the relief of inguinal hernia. This account of the dispo- 

 sition of the parts connected with the different forms of inguinal hernia 

 may be concluded by a brief statement of the application of the anatomical 

 facts in practical surgery, either in simply replacing the hernial protrusion, 

 or in the operation required to attain that object when the hernia is other- 

 wise irreducible. In the efforts to effect the replacement of the protruded 

 parts (the taxis), it is to be borne in mind that the abdominal muscles, 

 which, in most cases, are the sole obstacle to the attainment of that end, 

 become relaxed to some extent by flexing the thigh and inclining the trunk 

 forwards. The direction, too, which the protruded part follows through 

 the abdominal walls, ought to influence the direction given to the pressure 

 required in restoring it. 



When the operation required to set free the constriction which prevents 

 the restoration of the protruded viscus to the abdomen is undertaken, the 

 parts covering the hernia or a portion of it at the upper end, are to be 

 divided, so as to allow the introduction of a knife beneath the " stricture"; 

 and this (the stricture) will be found at the external ring, or, more fre- 

 quently, at the internal one. To accomplish the object, the tendon of the 

 external oblique is to be laid bare by an incision beginning somewhat above 

 the upper end of the hernia, and extending downwards below the external 

 ring. If, on examination, the stricture should be ascertained to be at the 

 last-named opening, the division of a few fibres of its circumference will 

 allow a sufficient dilatation for the replacement of the hernia ; but if, as 

 generally happens, the seat of the stricture should prove to be higher up, 

 in the inguinal canal or at the internal ring, the aponeurosis of the external 

 oblique is to be cut through over the canal, and the lower edge of the in- 

 ternal muscles, one of which commonly constitutes the stricture, is then to 

 be divided on a director insinuated beneath them. 



In the operation indicated in the last paragraph, the sac of the hernia is 

 supposed to be left unopened, the course which it is best to adopt when 

 the stricture is external to that membrane. Occasionally, however, it 

 happens that the sac itself is the cause of the constriction. When this is the 

 case, or when from some other reason the surgeon is unable, after such an 

 operation as that above noticed, to replace the hernia, it becomes necessary 

 to lay the sac open, in order to divide the constriction at its neck. When 

 the incision required in the last-mentioned step of the operation is being 

 made, the epigastric artery is not to be overlooked. From the position 

 which that vessel holds with respect to the oblique and direct forms of 

 hernia respectively, it necessarily follows that an incision outwards through 

 the neck of the sac, in the former variety of the disease, and inwards in the 

 latter, would be free from rik on account of the artery ; but, inasmuch as 

 the oblique hernia is liable, in time, to assume the appearance of one pri- 

 marily direct, and a want of certainty as to the diagnosis must, on this 

 account, exist in certain cases, as, moreover, it is advantageous to pursue 

 one course which will be applicable in every case, the rule generally 

 adopted by surgeons in all operations for inguinal hernise, is to 

 carry the incision through the neck of the sac directly upwards from its 

 middle. 



