There is not much likelihood that hydrocele of the tunica vaginalis could, in its earlier stages, be mistaken for hernia : it commences below and increases in an upward direction, while a hernia proceeds from above downwards; and at first in eases of hydrocele, the ring, the cord, and all these parts can be accurately felt. As the disease proceeds and the water reaches the ring, a diagnosis is not so easy ; still in almost every case of rupture the testis and the cord, particularly the former, can be easily felt lying behind and at the bottom of the tumour, which is not the case in hydroeele. Besides, hydrocele is lighter as to weight ; it gives a sensation of fluctuation to the touch ; it never exhibits that soft doughy character that belongs to omental hernia : moreover it is diaphanous, and the light of a candle can be seen through it, if the tumour is examined in a darkened room.
A collection of water within the sheath of the cord must, I should think, be rather an infrequent occurrence ; at least it has not fallen to my lot to meet with many examples of it. Still the practitioner must be aware of the possibility of the disease, and that both from the nature of the accident that occasions it, and many of the accompanying symptoms, it may very readily be mistaken for hernia. A young man fell with his groin against the edge of a tub, and in an incredibly short space of time afterwards a colourless elastic tumour appeared in the usual situation of hernia.
Ile WIIS admitted into the Meath Hospital under the care of the late Mr. llewson, and though some years have now elapsed I can well recollect the variety of opinions pronounced upon it. It could be partially pushed up, but re-appeared instantly on the pressure being re moved : it was slightly influenced by coughing, and it was extremely tender to the touch. As the patient was not confined in the bowels, and in filet there was no urgency of symptom, no active treatment was adopted, and the tumour gradually disappeared. It had probably been an effusion of fluid into the sheath of the cord. The manner in which these diseases are said to be capable of discrimination is as follows. Let the tumour be pushed up if possible, and the finger of the operator still be pressed against the ring : if it is a hernia, such pressure will be sufficient to prevent a re-descent ; but if it is only a fluid, it will insinuate itself by the side of the finger and the tumour shortly re-appear. Scarpa* denies the sufficiency of this test in cases of °mental hernia of small size, when situated so high up as to occupy and dilate the inguinal ring, and asserts that he had repeatedly observed omental inguinal hernia of a cylin drical form, which, when scarcely returned, re appeared again as before without the patient having changed his posture or made the slight est exertion ; and in like manner hydroceles of the spermatic cord, which, when pushed beyond the ring, remained there as long as the patient kept himself in the supine posture without making an exertion. Ile seems to rely more on the difference of consistence and regularity of surface in the two tumours, and on the cir cumstance of the hydrocele being always broader inferiorly, contrary to what is observed in omental hernia.
A varicose enlargement of the spermatic vein is not easily confounded with hernia, unless it has increased to such a size as nearly to occupy that side of the scrotum : it is longer in pro portion to the diameter of the tumour than hernia usually is, and its surface is hard, knotty, and uneven.t These circumstances, however, arc not sufficient to remove all obscurity, and a farther investigation must be made by placing the patient in the horizontal position and endea vouring to empty the vessel ; then let him stand up whilst firm and accurate pressure is maintained upon the ring. if it is a hernia, the tumour will not re-appear; but if varieocele, it will return as speedily or perhaps more so than if no pressure had been made. Mr. Cofiest mentions that a varicose state of the cord may be combined with hernia, throwing great obscurity on the nature of the disease, and for obvious reasons increasing the diffi culty of its management.
Inguinal hernia by direct descent.-1 now proceed to offer a few remarks on the other form of inguinal hernia,—that by direct descent,* which occurs when, instead of passing through the canal, the protruded viscus is pushed out immediately behind the situation of the ex ternal ring, through which it passes directly. The inferior part of the inguinal canal is the weakest of all the parictes of the abdomen. Externally, independent of the external oblique muscle, it is protected as far as the external third or half of Poupart's ligament by the fleshy fibres of the internal oblique and trans. versalis muscles, and by the fascia transversalis, which is dense and strong in this situation, but becomes gradually weaker internally, and is nearly lost before it reaches the mesial line. More internally it is supported by the conjoined tendon of these muscles, but as it arches over the spermatic cord that portion of theperi toneal cavity which corresponds with the inferior and posterior part of the inguinal canal must depend on the fascia transversalis alone, now becoming weaker and less capable of resist ance. More internally still, and immediately behind the external ring, this region is best supported, and there are many natural obstacles to the production of hernia in this situation, Besides the fascim already mentioned as tending to prevent the separation of one pillar of the ring from the other, and thereby offer an ob. stacle to the passage of any viscus through it, there is anothert of a triangular shape arising by a pretty broad base from the crest of the pubis, and inserted into the linea alba for about an inch or an inch and a quarter. It lies behind the tendon of the external oblique, and before that of the internal oblique and trans. versalis, which latter it strengthens materially, and its external edge contributes to close up a part of the external ring. The edge of the rectus muscle extends itself laterally sufficiently far to occupy one-half or one-third of the space behind the external ring, and moreover here the conjoined tendon is particularly strong. Not. withstanding these supports, this part is weak ; and yet when a hernia occurs here, it is not in consequence of yielding or stretching, but be cause the conjoined tendon actually undergoes laceration.