For the first two inches or two inches and a half of its separate existence, the superficial femoral lies in Scarpa's triangle, covered, as we said, only by skin and fascia. This triangle is formed by the sartorius and adductor longus muscles which meet at its apex, and by Poupart's ligament, which defines its base. The artery lies almost exactly in the centre of the space, and at the apex is covered by the sartorius muscle. The spot where it goes under the sartorius is the one selected for the application of the ligature. The femoral vein lies to the inner side of the femoral artery in this triangle, but their mutual relations vary with the portion of the limb; for, on the level of Poupart's ligament, the artery and vein lie side by side on the same plane, but in different compartments of their sheath; as the artery dives below the sartorius, the vein is still on the inside, but on a plane slightly posterior; while, by the time they reach Hunter's canal, the vein has got completely behind the artery. The separate compartments of the sheath in which the vessels lie are much less marked as the vessels go down the limb, the septum between the artery and the vein being in most cases very ill marked, even at the level where the ligature is applied. The anterior crural nerve, which on the level of Poupart's ligament lay outside of the artery and on a plane somewhat posterior, has divided into numerous branches before it reaches the point of ligature. One of its branches requires to be mentioned, and may sometimes be noticed and avoided during the operation, namely the internal saphenous nerve, which, first lying external to the artery, crosses it in front, reaching its inner side just before it enters Hunter's canal, where it leaves the vessel accompanying the anastomotica magna branch.

Operation of Ligature of the Femoral—Scarpa's Space.—The patient being placed on his back, and being brought very thoroughly under chloroform, the knee of the affected limb should be bent at an angle of about 120°, and supported on a pillow. Having previously ascertained the angle of junction of the sartorius and adductor, the surgeon should make an incision (Plate I. fig. 5) just over the pulsations of the vessel, in the middle line of the space, having its lower end quite over the sartorius muscle, and its upper one, at a distance from two and a half to three and a half inches, varying according to the amount of fat and muscle. The saphena vein can generally be recognised, and is almost always safe out of the way of this incision at its inner side.

The first incision should divide the skin, superficial fascia, and fat, quite down to the fascia lata. The edges of the wound being held apart, the fascia should be carefully divided, and the sartorius exposed; its fibres can generally be easily enough recognised by their oblique direction; once recognised, the fascia should be dissected from it till its inner edge be gained, the corner of which should then be turned so that it may be held outwards by an assistant with a blunt hook. The sheath of the vessels is now exposed, and after having thoroughly satisfied himself of the position of the artery by the pulsation, the surgeon should carefully raise a portion of the sheath with the dissecting forceps, and open it freely enough to allow the coats of the artery to be distinctly seen. If the parts are deep, as in a fat or muscular patient, great advantage will be gained by seizing one edge of the sheath by a pair of spring forceps, and committing it to the care of an assistant, while the operator holds the other in his dissecting forceps; there is thus no fear of losing the orifice of the sheath, which without this precaution may easily happen, from the parts being confused with blood, or the position altered by movements of the patient. Now comes the stage of the operation on which, more than on anything else, success or failure depends. A small portion of the vessel must be cleaned for the reception of the ligature, and it must be thoroughly cleaned, so that the needle may be passed round it without bruising of the coats, or rupture of an unnecessary number of the vasa vasorum by rough attempts to force a passage for it. Hence all compromises, such as blunted instruments, silver knives, and the like, are dangerous, for in trying to avoid the Scylla of wounding the artery, they fall into the Charybdis, on the one hand, of isolating too much of the vessel and causing gangrene from want of vascular supply, or, on the other, expose the vein to the danger of injury by the aneurism-needle in their attempts to force it round an uncleaned vessel.

The needle should in most cases be passed from the inner side, care being taken to avoid including the vein which is on the inner side and behind the vessel; the internal saphenous nerve, if seen, should be avoided. The needle must not be passed quite round the vessel raising it up, still less must the vessel be held up on the needle, as used to be done, as if the surgeon was surprised at his own success, but the needle should be passed just far enough to expose the end of the ligature, which must be seized by forceps and cautiously drawn through. It must then be tied very firmly and secured with a reef knot.

The edges of the wound must be brought into accurate apposition, and secured by one or two stitches. If antiseptics are used, drainage should be provided for.

From the very fact that ligature of the superficial femoral is a remarkably successful operation in causing consolidation of the aneurism and a rapid cure, there is also a corresponding danger that the limb be not sufficiently supplied with blood at first. The limb may very possibly become cold, and remain so for some hours at least after the operation. To avoid this as far as possible, it should be wrapped in cotton wadding, and very great care should be taken that it be not over-stimulated by hot applications, friction, or the like, any of which measures might very likely excite reaction, which would result in gangrene.

Complete rest of the limb and of the whole body must be enjoined; the food must be nourishing and in moderate quantity. The chief danger is from gangrene of the limb, which is especially apt to result when the vein is wounded, or even too much handled during the operation.

When properly performed, and in suitable cases, the operation is very successful. Mr. Syme tied this artery for aneurism thirty-seven times, and of these every one recovered. The statistics of Norris and Porta, who collected all the cases in which ligature of the femoral had been employed for any cause, show a mortality of somewhat less than one in four. Rabe's table up to 1869 with the additional cases collected by Mr. Barwell to 1880 gives 297 cases with 53 deaths.⁹ Mr. Hutchinson's table, again, of fifty cases collected from the records of Metropolitan Hospitals, shows the very startling result of sixteen deaths out of the fifty cases, or a mortality, in round numbers, of one-third.

Certain anomalies have been observed in the distribution of the femoral vessels, of some importance as affecting the possibility of applying, and the result of, ligature; such as—1. A high division of the branches which afterwards become posterior tibial and peroneal. 2. A double superficial femoral, both branches of which may unite and form the popliteal, as in Sir Charles Bell's well-known case. 3. Absence of the artery altogether, as in Manec's case, where the popliteal was a continuation of an immensely enlarged sciatic.

In such a case the absence of pulsation in front, and the presence of increased pulsation behind the limb, ought to prevent any fruitless attempt at search.

Ligature of the Superficial Femoral below the Sartorius Muscle.—This operation, though once common in France, and though the one recommended by Hunter himself, is now comparatively little used in this country; and rightly so; for while it has no advantage over the upper position, it is at once nearer the seat of disease, and the vessel is more deeply buried under muscles, and has a more distinct fibrous sheath, which requires division.

It is, however, by no means a difficult operation, and is thus performed:—

The limb being laid as before on the outside, and slightly bent, the skin shaved and the pulsation of the artery detected, an incision (Plate I. fig. 6) must be made from the lower edge of the sartorius muscle just as it crosses the vessel, along the course of the vessel, avoiding if possible the internal saphena vein.

The sartorius when exposed must be drawn inwards. The fibrous canal filling the interspace between the abductor magnus and vastus internus is then recognised, and must be fairly opened; the artery is now seen lying in it, and over the vein which is posterior to it, but projects slightly on its outer side; the internal saphenous nerve is lying on the artery. The needle is best passed from without inwards so as to avoid the vein. The anastomotica magna is sometimes a large trunk, and has been mistaken for the femoral in this situation, and tied instead of it.

Ligature of the Popliteal.—This operation is now hardly ever performed for aneurism, ligature of the superficial femoral having quite superseded it, and it is very rarely required for wounds, from the manner in which the vessel is protected by its position.

Before the invention of the Hunterian principle of ligature at a distance, the old operation for popliteal aneurism consisted in cutting into the space, clearing out the contents of the aneurismal sac, and tying both ends of the vessel; from the depth of parts and the close connection of the popliteal vein, this operation was very rarely successful, and is now quite given up. If the vessel is wounded the bleeding point is the object to be aimed at, and is generally sufficient guide.

In cases of hæmorrhage for suppuration of an aneurismal sac, it might possibly be advisable, and there are certain cases of rupture of the artery, without the existence of an external wound, in which attempts have been made to save the limb by tying the vessel.¹⁰ From the complexity of the parts, the numerous tendons, veins, and nerves crowded together in a narrow hollow, and chiefly from the great depth at which the artery lies, any attempt at ligature is very difficult. It is least so at the lower angle of the space, where, between the heads of the gastrocnemius, the vessel comes more to the surface, but is still overlapped by muscle.

Operation.—The patient lying on his face, a straight incision (Plate III. fig. 1), at least four inches in length, should be made over the artery, and thus nearer the inner than the outer hamstring; a strong fibrous aponeurosis will require division after the skin and superficial fascia are cut through, the limb is then to be flexed, and the tendons drawn aside with strong retractors; fat and lymphatic glands must next be dissected through, and then the vein and artery, lying on a sort of sheath of condensed cellular tissue, are seen, the vein lying above the artery and obscuring it. The vein must be drawn to the outside, and the thread passed round the artery, which lies close to the bone, on the ligamentum posticum of Winslowe.

It is a very difficult subject to decide what operations should be described in a work of this character, on the vessels of the leg and foot. A very large number of distinct methods of operations on the various parts of the three chief arteries of the leg have been described by surgeons and anatomists, but specially by the latter.

The fact is, however, that these complicated procedures are rarely required, for aneurisms of the arteries of the leg and foot are almost unknown, while in cases of wound of the vessel, or rupture resulting in traumatic aneurism, the proper treatment is not to tie the vessel higher up, but by dilating the wound and clearing out the clots, if required, to secure the bleeding point, and tie the vessel above and below.

Again, a wound of the sole of the foot often gives rise to very severe and persistent hæmorrhage, while the fasciæ and complicated tendons render ligature of the vessel at the spot very difficult; yet ligature of either the anterior or posterior tibial would probably be insufficient; and to tie both these vessels, with possibly the peroneal and interosseous as well, would be a much more severe and dangerous procedure than ligature of the superficial femoral; while probably careful plugging of the wound, combined with flexion of the knee, will be found to stop the hæmorrhage sooner than either of the more formidable methods.

A competent knowledge of the anatomy of the part, and of the ordinary methods of checking hæmorrhage, such as ligatures, graduated compresses, and styptics, aided by position, specially flexion of the knee after Mr. Ernest Hart's method, will suffice to enable the surgeon to check any hæmorrhage of the foot or leg, without it being necessary to burden the memory with the three positions in which to tie the peroneal, or the various methods, more or less bloody and tedious, by which the posterior tibial in its upper third may be secured.

Note.—While, as a matter of surgical principle to guide our practice on the living, I still hold very strongly the opinions here expressed against special operations for ligature of the arteries of the leg, and allow the sentences to stand as in the first edition of this work, I insert in a note a brief description of the more important ones, in deference to the advice of friends and the urgent request of pupils, as these operations are used by Examining Boards as tests of the operative dexterity of candidates:—

1. Anterior Tibial Artery in lower half of Leg.—Anatomical Note.—This vessel is related on its tibial side to the tibialis anticus, and on its fibular, to the extensor longus digitorum above, and the extensor pollicis below. The anterior tibial nerve lies first on its outer side, then crosses the artery, and eventually reaches its inner side near the foot. Operation.—An incision, at least three inches long, parallel with the outer edge of the tibia, and about three-quarters of an inch from it, exposes the deep fascia. This being divided, the outer edge of the tibialis anticus must be found, and will be the guide to the artery, which, surrounded by its venæ comites, lies very deeply between the muscles.

2. Posterior Tibial.—A. In middle third of leg. Here the artery is separated from the inner border of the tibia, by the flexor longus digitorum, and is covered by the soleus. Operation.—An incision at least four inches long, along the inner margin of the tibia, exposes the edge of the gastroenemius; then divide the tendinous attachment, then expose the soleus, and divide its attachment also; the deep fascia will then be seen; slit it up, and the vessel will be found about an inch internal to the edge of the bone. The nerve is there just crossing it.

Guthrie's, or the direct operation, has the very high authority of the late Professor Spence in its favour. An incision through skin and fascia in the middle of the back of the leg allows the two heads of the gastrocnemius to be separated to the same extent. The soleus is then to be scraped through in same direction, and its deep aponeurotic surface carefully slit up. The artery and vein are then easily seen.

B. In lower third of leg.—This is an easier and more scientific operation, as it does not involve the division of great tendons. An incision midway between the internal malleolus and the tendo Achillis, parallel with both, will expose the very deep and strong fascia in which the tendons lie. The artery, with its venæ comites, occupies a central position, having the tendons of the tibialis posticus and flexor communis in front between it and the internal malleolus, and the posterior tibial nerve behind it, while the flexor longus pollicis lies still nearer the tendo Achillis.

Table illustrating anastomotic circulation after ligature of arteries of lower limb.

1. Aorta.—Epigastric and mammary of both sides. Hæmorrhoidal and spermatic, with branches of pudic both deep and superficial.

2. Common Iliac.—Internal iliac and branches, with those of the other side, along with the following:—

3. External Iliac.—Internal mammary and deep epigastric.

Iliolumbar and lumbar branches of aorta, with deep circumflex ilii.

Pudic from internal iliac, with superficial pudic of common femoral.

Gluteal, sciatic, and obturator, with the circumflex and perforating branches or deep femoral.

4. Femoral.—External circumflex, with external articular of popliteal.

Perforating, with branches of gluteal and sciatic.

Profunda branches with anastomotica and articular branches.

Obturator and internal circumflex with anastomotica and superior internal articular.

Note.—The importance of the articular branches of the popliteal explain the danger of gangrene after a sudden rupture or increase in size of a popliteal aneurism.

Ligature of the Innominate.—The performance of this extremely dangerous, in fact almost hopeless operation, is by no means so difficult as might be expected.

The patient lying down with the shoulders raised and head thrown well back, the sternal attachment of the right sterno-mastoid must be very freely exposed. This may be done by an incision (Plate I. fig. 7) along its anterior edge from the upper edge of the sternum, as far as may be necessary; another about the same length along the upper edge of the clavicle, will meet the former at an acute angle, and will include a triangular flap of skin, which must be carefully dissected up. The sternal, and probably a portion of the clavicular attachment of the right sterno-mastoid, must then be cautiously divided. This being done, the sterno-hyoid and sterno-thyroid muscles require division immediately above their sternal attachments.