FEMORAL HERNIA. 1061 



canal. The septum crurale is perforated by numerous apertures for the passage of 

 lymphatic vessels connecting the deep inguinal lymphatic glands with those sur- 

 rounding the external iliac artery. 



The size of the femoral canal, the degree of tension of its orifices, and con- 

 sequently the degree of constriction of a hernia, vary according to the position of 

 the limb. If the leg and thigh are extended, abducted, or everted, the femoral 

 canal and its orifices are rendered tense from the traction on these parts by 

 Poupart's ligament and the fascia lata, as may be ascertained by passing the finger 

 along the canal. If, on the contrary, the thigh is flexed upon the pelvis, and at 

 the same time adducted and rotated inward, the femoral canal and its orifices 

 become considerably relaxed ; for this reason the limb should always be placed in 

 the latter position when the application of the taxis is made in attempting the 

 reduction of a femoral hernia. 



The subperitoneal areolar tissue is continuous with the subserous areolar tissue 

 of surrounding parts. It is usually thickest and most fibrous where the iliac 

 vessels leave the abdominal cavity. It covers over the small interval (crural ring) 

 on the inner side of the femoral vein. In some subjects it contains a considerable 

 amount of adipose tissue. In such cases, where it is protruded forward in front 

 of the sac of a femoral hernia, it may be mistaken for a portion of omentum. The 

 peritoneum lining the portion of the abdominal wall between Poupart's ligament 

 and the brim of the pelvis is similar to that lining any other portion of the abdominal 

 wall, being very thin. It has here no natural aperture for the escape of intestine. 



Descent of the Hernia. From the preceding description it follows that the 

 femoral ring must be a weak point in the abdominal wall : hence it is that when 

 violent or long-continued pressure is made upon the abdominal viscera a portion 

 of intestine may be forced into it, constituting a femoral hernia; and the changes 

 in the tissues of the abdomen which are produced by pregnancy, together with the 

 larger size of this aperture in the female, serve to explain the frequency of this 

 form of hernia in women. 



When a portion of the intestine is forced through the femoral ring, it carries 

 before it a pouch of peritoneum, which forms what is called the hernial sac ; it 

 receives an investment from the subserous areolar tissue and from the septum 

 i-rurale. and descends vertically along the crural canal in the inner compartment of 

 the sheath of the femoral vessels as far as the saphenous opening ; at this point it 

 changes its course, being prevented from, extending farther down the sheath on 

 account of the narrowing of the sheath and its close contact with the vessels, and 

 also from the close attachment of the superficial fascia and crural sheath to the 

 lower part of the circumference of the saphenous opening ; the tumor is conse- 

 quently directed forward, pushing before it the cribriform fascia, and then curves 

 upward on to the falciform process of the fascia lata and lower part of the tendon 

 of the External oblique, being covered by the superficial fascia and integument. 

 While the hernia is contained in the femoral canal it is usually of small size T 

 owing to the resisting nature of the surrounding parts; but when it has escaped 

 from the saphenous opening into the loose areolar tissue of the groin, it becomes 

 considerably enlarged. The direction taken by a femoral hernia in its descent is 

 at first downward, then forward and upward ; this should be borne in mind, as 

 in the application of the taxis for the reduction of a femoral hernia pressure should 

 be directed in the reverse order. 



Coverings of the Hernia. The coverings of a femoral hernia, from within 

 outward, are peritoneum, subserous areolar tissue, the septum crurale, crural 

 sheath, cribriform fascia, superficial fascia, and integument. 1 



1 Sir Astley Cooper has described an investment for femoral hernia, under the name of "fascia 

 propria," lying immediately external to the peritoneal sac, but frequently separated from it by more 

 or less adipose tissue. Surgically, it is important to remember the existence (at any rate, the occa- 

 sional existence) of this layer, on account of the ease with which an inexperienced operator may mis- 

 take the fascia for the peritoneal sac and the contained fat for omentnm. Anatomically, this fascia 

 appears identical with what is called in the text "subserous areolar tissue," the areolar tissue being 

 thickened and caused to assume a membranous appearance by the pressure of the hernia. 



