Surgical Anatomy Part 12

PLATE 12.

A. Axillary vein, cut and tied; a, the basilic vein, cut.

B. Axillary artery; b, brachial artery, in the upper part of its course, having h, the median nerve, lying rather to its outer side; b*, the artery in the lower part of its course, with the median nerve to its inner side.

C. Subclavius muscle.

C*. Clavicle.

D. Axillary plexus of nerves, of which d is a branch on the coracoid border of the axillary artery; e, the musculo-cutaneous nerve, piercing the coraco-brachialis muscle; f, the ulnar nerve; g, musculo-spiral nerve; h, the median nerve; i, the circ.u.mflex nerve.

E. Humeral part of the great pectoral muscle.

F. Biceps muscle.

G. Coraco-brachialis muscle.

H. Thoracic half of the lesser pectoral muscle.

I. Thoracic half of the greater pectoral muscle.

K. Coracoid attachment of the lesser pectoral muscle.

K*. Coracoid process of the scapula.

L. Lymphatic glands.

M. Serratus magnus muscle.

N. Latissimus dorsi muscle.

O. Teres major muscle.

P. Long head of triceps muscle.

Q. Inner condyle of humerus.

[Ill.u.s.tration: Right arm, showing blood vessels, muscles and other internal organs.]

Plate 12

COMMENTARY ON PLATES 13 & 14.

THE SURGICAL FORM OF THE MALE AND FEMALE AXILLAE COMPARED.

Certain characteristic features mark those differences which are to be found in all corresponding regions of both s.e.xes. Though the male and female bodies, in all their regions, are anatomically h.o.m.ologous or similar at basis, yet the const.i.tuent and corresponding organs of each are gently diversified by the plus or minus condition, the more or the less, which the development of certain organs exhibits; and this diversity, viewed in the aggregate, const.i.tutes the s.e.xual difference.

That diversity which defines the s.e.xual character of beings of the same species, is but a link in that extended chain of differential gradation which marks its progress through the whole animal kingdom. The female breast is a plus glandular organ, situated, pendent, in that very position where, in a male body, the unevolved mamma is still rudimentarily manifested.

The male and female axillae contain the same number and species of organs; and the difference by which the external configuration of both are marked mainly arises from the presence of the enlarged mammary gland, which, in the female, Plate 14, masks the natural outline of the pectoral muscle, E, whose axillary border is overhung by the gland; and thus this region derives its peculiarity of form, contrasted with that of the male subject.

When the dissected axilla is viewed from below, the arm being raised, and extended from the side, its contained parts, laid deeply in their conical recess, are sufficiently exposed, at the same time that the proper boundaries of the axillary cavity are maintained. In this point of view from which the axillary vessels are now seen, their relative position, in respect to the thorax and the arm, are best displayed. The thickness of that fleshy anterior boundary formed by both pectoral muscles, E F, Plate 13, will be marked as considerable; and the depth at which these muscles conceal the vessels, A B, in the front aspect of the thoracico-humeral interval, will prepare the surgeon for the difficulties he is to encounter when proceeding to ligature the axillary artery at the incision made through the anterior or pectoral wall of this axillary s.p.a.ce.

The bloodvessels of the axilla follow the motions of the arm; and according to the position a.s.sumed by the arm, these vessels describe various curves, and lie more or less removed from the side of the thorax. While the arm hangs close to the side, the axillary s.p.a.ce does not (properly speaking) exist; and in this position, the axillary vessels and nerves make a general curve from the clavicle at the point K, Plate 14, to the inner side of the arm, the concavity of the curve being turned towards the thoracic side. But when the arm is abducted from the side, and elevated, the vessels which are destined to supply the limb follow it, and in this position they take, in reality, a serpentine course; the first curve of which is described, in reference to the thorax, from the point K to the head of the humerus; and the next is that bend which the head of the humerus, projecting into the axilla in the elevated position of the member, forces them to make around itself in their pa.s.sage to the inner side of the arm. The vessels may be readily compressed against the upper third of the humerus by the finger, pa.s.sed into the axilla, and still more effectually if the arm be raised, as this motion will rotate the tuberous head of the humerus downwards against them.

The vessels and nerves of the axilla are bound together by a fibrous sheath derived from the membrane called costo-coracoid; and the base or humeral outlet of this axillary s.p.a.ce, described by the muscles C, K, E, G, Plate 13, is closed by a part of the fascial membrane, g, extended across from the pectoral muscle, E, to the latissimus dorsi tendon, K.

In the natural position of the vessels at that region of their course represented in the Plates, the vein A overlies the artery B, and also conceals most of the princ.i.p.al nerves. In order to show some of these nerves, in contact with the artery itself, the axillary vein is drawn a little apart from them.

The axillary s.p.a.ce gives lodgment to numerous lymphatic glands, which are either directly suspended from the main artery, or from its princ.i.p.al branches, by smaller branches, destined to supply them. These glands are more numerous in the female axilla, Plate 14, than in the male, Plate 13, and while they seem to be, as it were, indiscriminately scattered here and there through this region, we observe the greater number of them to be gathered together along the axillary side of the great pectoral muscle; at which situation, h, in the diseased condition of the female breast, they will be felt to form hard, nodulated ma.s.ses, which frequently extend as far up through the axillary s.p.a.ce as the root of the neck, involving the glands of this latter region also in the disease.

The contractile motions of the pectoral muscle, E, of the male body, Plate 13, are during life readily distinguishable; and that boundary which it furnishes to the axillary region is well defined; but in the female form, Plate 14, the general contour of the muscle E, while in motion, is concealed by the hemispherical mammary gland, F, which, surrounded by its proper capsule, lies loosely pendent from the fore part of the muscle, to which, in the healthy state of the organ, it is connected only by free-moving bonds of lax cellular membrane. The motions of the shoulder upon the trunk do not influence the position of the female mammary gland, for the pectoral muscle acts freely beneath it; but when a scirrhus or other malignant growth involves the mammary organ, and this latter contracts, by the morbid ma.s.s, a close adhesion to the muscle, then these motions are performed with pain and difficulty.

When it is required to excise the diseased female breast, (supposing the disease to be confined to the structure of the gland itself,) the operation may be performed confidently and without difficulty, in so far as the seat of operation does not involve the immediate presence of any important nerves or bloodvessels. But when the disease has extended to the axillary glands, the extirpation of these (as they lie in such close proximity to the great axillary vessels and their princ.i.p.al branches) requires cautious dissection. It has more than once happened to eminent surgeons, that in searching for and dissecting out these diseased axillary glands, H, h, Plate 14, the main artery has been wounded.

As the coracoid process points to the situation of the artery in the axilla, so the coraco-brachialis muscle, C, marks the exact locality of the vessel as it emerges from this region; the artery ranges along the inner margin of both the process and the muscle, which latter, in fleshy bodies, sometimes overhangs and conceals it. When the vessel has pa.s.sed the insertion of the coraco-brachialis, it becomes situated at the inner side of the biceps, which also partly overlaps it, as it now lies on the forepart of the brachialis anticus. As the general course of the artery, from where it leaves the axilla to the bend of the elbow, is one of winding from the inner side to the forepart of the limb, so should compression of the vessel, when necessary, be directed in reference to the bone accordingly--viz., in the upper or axillary region of the arm, from within outwards, and in the lower part of the arm, from before backwards.

All incised, lacerated, or contused wounds of the arm and shoulder, happening by pike, bayonet, sabre, bullet, mace, or arrow, on the outer aspect of the limb, are (provided the weapon has not broken the bones) less likely to implicate the great arteries, veins, and nerves. These instruments encountering the inner or axillary aspect of the member, will of course be more likely to involve the vessels and nerves in the wound. In severe compound fractures of the humerus occurring from force applied at the external side of the limb, the brachial vessels and nerves have been occasionally lacerated by the sharp jagged ends of the broken bone,--a circ.u.mstance which calls for immediate amputation of the member.

The axilla becomes very frequently the seat of morbid growths, which, when they happen to be situated beneath the dense axillary fascia, and have attained to a large size, will press upon the vessels and nerves of this region, and cause very great inconvenience. Adipose and other kind of tumours occurring in the axilla beneath the fascia, and in close contact with the main vessels, have been known to obstruct these vessels to such a degree, as to require the collateral or anastomatic circulation to be set up for the support; of the limb. When abscesses take place in the axilla, beneath the fascia, it is this structure which will prevent the matter from pointing; and it is required, therefore, to lay this fascia freely open by a timely incision. The accompanying Plates will indicate the proper direction in which such incision should be made, so as to avoid the vessels A, B. When the limb is abducted from the side, the main vessels and nerves take their position parallel with the axis of the arm. The axillary vessels and nerves being thus liable to pressure from the presence of large tumours happening in their neighbourhood, will suggest to the pract.i.tioner the necessity for fashioning of a proper form and size all apparatus, which in fracture or dislocation of the shoulder-bones shall be required to bear forcibly against the axillary region. While we know that the locality of the main vessels and nerves is that very situation upon which a pad or fulcrum presses, when placed in the axilla for securing the reduction of fractures of the clavicle, the neck of the humerus, or scapula, so should this member of the fracture apparatus be adapted, as well to obviate this pressure upon these structures, as to give the needful support to the limb in reference to the clavicle, &c. The habitual use, for weeks or more, of a hard, resisting fulcrum in the axilla, must act in some degree like the pad of a tourniquet, arresting the flow of a vigorous circulation, which is so essential to the speedy union of all lesions of bones. And it should never be lost sight of, that all grievously coercive apparatus, which incommode the suffering patient, under treatment, are those very instruments which impede the curative process of Nature herself.

The anatomical mechanism of the human body, considered as a whole, or divisible into regions, forms a study so closely bearing upon practice, that the surgeon, if he be not also a mechanician, and fully capable of making his anatomical knowledge suit with the common principles of mechanics, while devising methods for furthering the efforts, of Nature curatively, may be said to have studied anatomy to little or no purpose.

The shoulder apparatus, when studied through the principle of mechanics, derives an interest of practical import which all the laboured description of the schools could never supply to it, except when ill.u.s.trating this principle.

The disposal of the muscular around the osseous elements of the shoulder apparatus, forms a study for the surgeon as well in the abnormal condition of these parts, as in their normal arrangement; for in practice he discovers that that very mechanical principle upon which both orders of structures (the osseous and muscular) are grouped together for normal articular action, becomes, when the parts are deranged by fracture or, other accident, the chief cause whereby rearrangement is prevented, and the process of reunion obstructed. When a fracture happens in the shaft of the humerus, above or below the insertions of the pectoral and latissimus dorsi muscles, these are the very agents which when the bone possessed its integrity rendered it functionally fitting, and which, now that the bone is severed, produce the displacement of the lower fragment from the upper one. To counteract this source of derangement, the surgeon becomes the mechanician, and now, for the first time, he recognises the necessity of the study of topographical anatomy.

When a bone is fractured, or dislocated to a false position and retained there by the muscular force, the surgeon counteracts this force upon mechanical principle; but while he puts this principle in operation, he also acknowledges to the paramount necessity of ministering to the ease of Nature as much as shall be consistent with the effectual use of the remedial agent; and in the present state of knowledge, it is owned, that that apparatus is most efficient which simply serves both objects, the one no less than the other. And, a.s.suming this to be the principle which should always guide us in our treatment of fractures and dislocations, I shall not hesitate to say, that the pad acting as a fulcrum in the axilla, or the perineal band bearing as a counterextending force upon the groin (the suffering body of the patient being, in both instances, subjected for weeks together to the grievous pressure and irritation of these members of the apparatus), do not serve both objects, and only one incompletely; I say incompletely, for out of every six fractures of either clavicle or thigh-bone, I believe that, as the result of our treatment by the present forms of mechanical contrivances, there would not be found three cases of coaptation of the broken ends of the bone so complete as to do credit to the surgeon. The most pliant and portable of all forms of apparatus which const.i.tute the hospital armamentaria, is the judgment; and this cannot give its approval to any plan of instrument which takes effect only at the expense of the patient.

DESCRIPTION OF PLATES 13 & 14.

PLATE 13.

A. Axillary vein, drawn apart from the artery, to show the nerves lying between both vessels. On the bicipital border of the vein is seen the internal cutaneous nerve; on the tricipital border is the nerve of Wrisberg, communicating with some of the intercosto-humeral nerves; a, the common trunk of the venae comites, entering the axillary vein.

B. Axillary artery, crossed by one root of the median nerve; b, basilic vein, forming, with a, the axillary vein, A.

C. Coraco-brachialis muscle.

D. Coracoid head of the biceps muscle.

E. Pectoralis major muscle.

F. Pectoralis minor muscle.

G. Serratus magnus muscle, covered by g, the axillary fascia, and perforated, at regular intervals, by the nervous branches called intercosto-humeral.

H. Conglobate gland, crossed by the nerve called "external respiratory"

of Bell, distributed to the serratus magnus muscle. This nerve descends from the cervical plexus.