Lumbar or psoas abscess is another affection that may be confounded with femoral hernia, and Al r. Colles states that lie had known the mistake to have been committed. These diseases resemble each other in the following circum stances. Both present very nearly in the same situation at the bend of the groin, are firm and elastic; coughing gives to each the same or a similar impulse; and there are eases on record in which psoas abscess disappeared under pres sure or by the patient assuming the recumbent posture. Yet I think the two cases not very difficult of distinction. Psoas abscess is a dis ease of youth; it does not often occur in the adult except as a critical abscess after fever, or in connexion with caries and curvature of the spine, in either of which cases the collateral circumstances will point itout ; whereas femoral hernia is the disease of married women, and of course will not be likely to occur at the same period of life with the abscess. A sense of fluctuation is generally perceptible in psoas abscess; not su with hernia. The abscess is preceded by pain and weight in the loins and by shivering. It is a scrofulous complaint, and there will probably be other indications of the diathesis, such as the transparent skin, the thickened tipper lip, or perhaps ill-conditioned scars about the neck. Any of these symptoms taken singly may prove but an indifferent dia gnostic, but in the aggregate they establish such distinction that it must be the result of sad in attention or of actual ignorance if any serious mistake is committed.
It has been stated that a varix of the saphena vein may present symptoms and appearances strongly resembling crural hernia, inasmuch as the tumour disappears under pressure or in the horizontal posture, and returns again imme diately on these influences being removed, and also as it receives a certain degree of impulse from coughing or sneezing. From anatomical considerations it would almost seem impossible that such an error could be committed, and at first sight the observation seems to have been made for the purpose of creating nice distinc tions and rendering the subject apparently com plete rather than for any practical utility. A case, however, is related by Petit, who distin guished the real nature of the tumour by its dark-coloured appearance and by the general varicose state of the remainder of the vein. If difficulty is experienced in any particular case, it may be easily resolved by making pressure on the trunk of the iliac vein above Poupart's ligament, when the tumour will re-appear, even although the patient maintains the horizontal posture.
" Fatty tumours are not unfrequently found on dissection occupying the exact situation of crural hernia. 1 have not had an opportunity of seeing any case of this kind in the living body, but have had occasion to remark at least five or six instances of it every season in the dissecting room, from which 1 presume such tumours are more common than is generally suspected. In all those instances the fatty tu mour was connected with or rather seemed to grow from the outer surface of the peritoneum lining the crural ring; and the inner surface of this m'mhrane when viewed from the abdomen had a contracted, wrinkled, and thickened ap pearance, resembling very closely the appearance of a reduced hernial sac. Whether the perito
neum had been protruded in these instances 1 cannot pretend to say ; nor can I venture to lay down the symptoms which should guide us in our diagnosis in the living body. This much at least is obvious, that these steatoma tons tumours will not be accompanied by symptoms of strangulation." Umbilical navel is the remnant of an aperture that had been situated nearly in the centre of the front of the belly,but nearer to the pubis than to the ensiform cartilage: it is placed in the linea alba, and of course its edges are tendinous. During feetal life it serves for the transmission of the umbilical vein and arte ries, but its size is greater than would merely suffice for the passage of these vessels, in order that the circulation of the blood through them should suffer no interruption by accidental com pression ; and in a foetus of seven months the edge of the aponeurotic opening is still thin, weak, and unresisting. After birth, when the navel string (as it is called) has dropped off, the umbilical aperture begins to close, until finally that puckered cicatrix is formed, the appearance of which is so familiar; but the periods at which this process commences and is completed, and the circumstances that may occur to interfere with it, are of some importance with reference to the phenomena of hernia. Scarpa says that it begins immediately, and that if the finger is passed up the peritoneal wall of the abdomen in a child two months after birth, not only will the navel be found firmly formed and completely cicatrised, but there will be a knot or elevation felt at this spot, spewing that it is then really stronger than most other parts of the abdominal parietes. Lawrence states that the contraction commences about the third or fourth month after birth, and thence inculcates the necessity of an infant being tolerably accu rately bandaged anterior to that period in order to prevent the occurrence of umbilical rupture from its struggles or its cries. It is not of much consequence which of these opinions may be correct : probably both are so to a cer tain extent, for the opening is larger in some infants than in others, and will require a longer time to close, and the process of obliteration does not commence in all exactly at the same period after birth. Whatever variety may exist in this respect, when the process is com plete the umbilicus can never afterwards be called an aperture; it never again re-opens; and when ruptures are observed in after-life seem ing to occupy this situation, it will be found on examination that some neighbouring parts of the linen alba have given way, and the disease more strictly belongs to the ventral than to umbilical hernia.