Fig. 609
Ischiatic hernia. (Richardson.)
Hernia into foramen of Winslow.
Lumbar Hernia.
—In so-called lumbar hernia, which is very rare, the hernia escapes along the outer border of the quadratus lumborum muscle into the triangle of Petit. Such a tumor, usually small, may be easily mistaken for lipoma or for cold abscesses.
Other anomalous types of hernia may occur in connection with congenital defects of the bones or the less dense structures of the pelvis proper.
Retroperitoneal and Properitoneal Hernia.
—Retroperitoneal and properitoneal hernia are types which seem to corroborate the views already enunciated concerning the essentially congenital origin of the ordinary forms. The former implies a protrusion into an internal peritoneal pouch, and is usually found in the upper abdominal cavity in the duodenojejunal fossa, although it may also occur lower down on either side. It will not be recognized save by its effects, which will usually be those of acute intestinal obstruction, and even then will only be diagnosticated after the operation which the condition will necessitate. Hernia through the foramen of Winslow has already been mentioned in the chapter on the Small Intestines. (See [Fig. 609].)
Properitoneal hernia implies usually the existence of a double sac, with a common opening, its inner portion lying between the peritoneum and the abdominal musculature, while its outer portion takes the usual position of the hernial sac, either the inguinal, the femoral, or the umbilical form. It may be suspected when reduction which has been apparently successful has later evidently failed. It occurs most often in the inguinal region, where it is usually referred to as inguinoproperitoneal hernia, and where it was first recognized by Parise, and later fully described by Krönlein. It may be with equal propriety called interstitial hernia, and is often associated with imperfect descent of the testicle, which perhaps has served to deflect the descending hernia in an unusual direction. The properitoneal sac is most often found between the internal ring and the anterior spine, although it may be directed downward and inward toward the bladder, or backward toward the iliac fossa. In size it is usually small as compared with the external portions. Its existence may be suspected when a patient with a hernia previously easily reducible suddenly develops strangulation, which is apparently relieved by taxis, only to recur a little later. So far as its radical treatment is concerned all that is necessary is the extirpation of the extra sac, with perhaps separate treatment of its neck, when dealing with the greater and more completely filled pouch in front ([Fig. 610]).