On the finger these muscles may be safely divided to the full extent of the external incision. The deep circumflex iliac artery if possible should not be divided, but may bleed smartly and require a ligature.
The peritoneum must then be very cautiously raised from the tumour, and supported, along with the intestines, by copper spatulæ. The surgeon will rarely succeed in obtaining anything like a satisfactory view of the vessel, but can expose it for the ligature by the aid of his finger-nail. An ordinary aneurism-needle will generally suffice for the conveyance of the ligature.
The difficulties may occasionally be much increased by special circumstances, such as great stoutness of the patient, and consequent thickness of the abdominal wall; or large size of the aneurism, which may cause alterations in the relation of parts and adhesion of the peritoneum. The ureter generally gives no trouble, as in pressing back the peritoneum it is adherent to it, and is removed along with it towards the middle line.
Results.—Are not by any means satisfactory.
Out of twenty-two cases in which the common iliac has been tied for aneurism, eight recovered and fourteen died; while out of thirteen cases where it required ligature for hæmorrhage after amputation, rupture of aneurism, etc., only one recovered.
Ligature of Internal Iliac.—Little need be added to the account just given of the operation for ligature of the common iliac, as precisely the same incisions are required. The operator having reached the bifurcation of the vessel, must, instead of tracing it upwards, endeavour to trace it downwards, and the same time inwards, into the basin of the pelvis. To do this his finger must cross the external iliac artery, which will pulsate under the joint of the ungual phalanx, while the pulp of the finger is touching the internal iliac,—the external iliac vein, which occupies the angle formed by the bifurcation of the artery, lying between these two points. The ligature should be applied within three-quarters of an inch from the bifurcation.
Anatomical Note.—This short thick trunk extends backwards and inwards (Ellis); downwards and backwards (Harrison), in front of the sacro-iliac synchondrosis, as far as the upper extremity of the great sacro-sciatic notch, a distance varying in the adult from one and a half to two inches in length. It forms a curve with its concavity forwards, and at its termination divides into, rather than gives off, its two or three principal branches. Its corresponding vein is in close contact behind, as also the lumbo-sacral nerve, the obdurator nerve to its outer side. The peritoneum covers it anteriorly, and it is crossed just at its commencement by the ureter. On the left side it is covered anteriorly by the rectum. Of its anatomical relations, that of the external iliac vein is perhaps the most important, as it is apt to interfere with the passing of the needle.
Results.—This vessel has been tied for aneurism of one or other of its branches, or for wound, about seventeen times.2 Of these seven recovered; in ten the operation proved fatal, in most of them from secondary hæmorrhage. In one case the hæmorrhage occurred within twelve hours after the operation. The circulation of the parts supplied after the ligature is carried on mainly by the lumbar and lateral sacral branches, which become much developed even before the operation, in cases of aneurism.
Ligature of External Iliac.—Anatomical Note.—This artery extends from the bifurcation of the common iliac to the centre of Poupart's ligament, where it leaves the abdomen, passing under the ligament, and becomes the common femoral. Its upper extremity is thus not always constant, varying in position from the sacro-lumbar fibro-cartilage to the upper end of the sacro-iliac synchondrosis, or even a little lower down. Thus, though the position of the lower end is at a fixed point, the artery varies in length. In an adult male of moderate stature it is from three and a half to four inches in length. On the surface of the abdomen the position of this vessel would be indicated by a line drawn from about an inch on either side of the umbilicus to the middle of the space between the symphysis pubis and the crest of the ilium. Its relations to neighbouring parts are as follows:—The peritoneum lies in front of it, separated from it only by a subperitoneal layer of loose fascia, in which the artery and vein lie, which varies much in consistence and amount, and which occasionally gives a good deal of trouble in the operation of ligature. Near its origin it is sometimes crossed by the ureter, and near its termination the genito-crural nerve lies on it. The spermatic vessels cross it, and occasionally a quantity of subperitoneal fat marks its course. Externally.—The fascia-iliaca and some fibres of the psoas muscle separate it from the anterior crural nerve, which lies outside of the vessel, and at a somewhat deeper level, hidden amid the fibres of psoas and iliacus. Internally.—The external iliac vein lies on the same plane, and to the inner side of the artery, at Poupart's ligament, on both sides of the body. As we trace it upwards we find that on the left side it lies internal to the artery in its whole course, while on the right side it becomes posterior to the artery as it approaches the bifurcation of the common iliac. Lastly, just before the vessel reaches Poupart, the circumflex iliac vein crosses it from within outwards.
Branches.—The two large branches to the wall of the abdomen, the epigastric and the circumflex iliac, rise a few lines above Poupart's ligament. Their position is unfortunately apt to vary upwards, to the extent of an inch and a half or even two inches, and they are important, as, besides being liable to be cut during the operation, their position very materially modifies the prognosis, as, if too high up, they interfere with the proper formation of the coagulum.
Operation.—Various plans of incision through the skin have been recommended by various operators, the chief difference being with regard to the part of the artery aimed at; the plan known as that of Mr. Abernethy, with various modifications, being intended to expose the artery pretty high up, and enable the surgeon to reach it from above; while the method going by the name of Sir Astley Cooper's exposes the lower part of the artery, and enables the surgeon to reach it from below. Though the latter is in some respects easier, the former method is generally to be preferred, being further from the seat of disease, and especially more out of the way of the epigastric and circumflex arteries.
The higher operation (Abernethy's modified).—An incision must be made through the skin about four inches in length, but longer in proportion to the amount of subcutaneous fat, and the depth of the pelvis, extending from a point one inch to the inside of the anterior superior spine of the ilium, to a point half an inch above the middle line of Poupart's ligament. It must be slightly curved, with its convexity looking outwards and downwards.3
The subcutaneous cellular tissue and the tendon of the external oblique may then be divided freely in the same line. Then at some one point or other (generally easiest below), the internal oblique and transversalis muscles must be cautiously scraped through with the aid of the forceps, till the transversalis fascia is reached; they may then be freely divided by a probe-pointed bistoury (guarded by the finger pushed up below the muscles) to the required extent. The muscles being held aside by flat copper spatulæ, the fascia transversalis must be carefully scratched through near the crest of the ilium, and thus the operator will be enabled to push the peritoneum inwards, and by the forefinger will easily recognise the pulsation of the artery lying on the soft brim of the pelvis.
A branch of the circumflex iliac artery will very likely be cut in dissecting through the muscles, and must be secured, as also any branches of the epigastric which may be divided in the incisions through the abdominal wall (ut supra, p. 5).
The operator should then, by pressing the peritoneum and its contents gently inwards, endeavour to see the vessel; if, from the depth of the pelvis, this cannot be done, the sense of touch will be in most cases sufficient to enable him to isolate the artery by the point of his finger-nail, or by the blunt aneurism-needle, from the vein. The ligature should be passed from the inner side to avoid including the vein, and thus there will be less chance of wounding the peritoneum from the