The Surgical Dissection Of The Wrist And Hand

Sources: Surgical Anatomy

A member of such vast importance as the human hand necessarily claims a

high place in regard to surgery. The hand is typical of the mind. It is

the material symbol of the immaterial spirit, It is the prime agent of

the will; and it is that instrument by which the human intellect

manifests its presence in creation. The human hand has a language of its

own. While the tongue demonstrates the thought through the word, the

and realizes and renders visible the thought through the work. This

organ, therefore, by whose fitness of form the mind declares its own

entity in nature, by the invention and creation of the thing, which is,

as it were, the mind's autograph, claims a high interest in surgical

anatomy; and accordingly the surgeon lays it down as a rule, strictly to

be observed, that when this beautiful and valuable member happens to be

seriously mutilated, in any of those various accidents to which it is

exposed, the prime consideration should be, not as to the fact of how

much of its quantity or parts it can be deprived in operation, but

rather as to how little of its quantity should it be deprived, since no

mechanical ingenuity can fashion an apparatus, capable of supplying the

loss of a finger, or even of one of its joints.



The main blood vessels and nerves of the arm traverse the front aspect

of the wrist, and are distributed chiefly to supply the palmar surface

of the hand, since in the palm are to be found a greater variety and

number of structures than are met with on the back of the hand. The

radial artery, A, Plate 17, occupies (as its name indicates) the radial

border of the forepart of the wrist, and the ulnar artery, C, Plate 17,

occupies the ulnar border; both vessels in this region of their course

lie parallel to each other; both are comparatively superficial, but of

the two, the radial artery is the more superficial and isolated, and

thereby occasions the radial pulse. The anatomical situation of the

radial artery accounts for the fact, why the pulsation of this vessel is

more easily felt than that of the ulnar artery.



The radial vessel, A, Plate 17, at the wrist, is not accompanied by the

radial nerve; for this nerve, C, Plate 19, passes from the side of the

artery, at a position, C, Plate 19, varying from one to two or more

inches above the wrist, to gain the dorsal aspect of the hand. The ulnar

artery, C, Plate 17, is attended by the ulnar nerve, D, in the wrist,

and both these pass in company to the palm. The ulnar nerve, D E, lies

on the ulnar border of the artery, and both are in general to be found

ranging along the radial side of the tendon of the flexor carpi ulnaris

muscle, T, and the pisiform bone, G. The situation of the radial artery

is midway between the flexor carpi radialis tendon, I, and the outer

border of the radius. The deep veins, called comites, lie in close

connexion with the radial and ulnar arteries. When it is required to lay

bare the radial or ulnar artery, at the wrist, it will be sufficient for

that object to make a simple longitudinal incision (an inch or two in

length) over the course of the vessel A or C, Plate 17, through the

integument, and this incision will expose the fascia, which forms a

common investment for all the structures at this region. When this

fascia has been cautiously slit open on the director, the vessels will

come into view. The ulnar artery, however, lies somewhat concealed

between the adjacent muscles, and in order to bring this vessel fully

into view, it will be necessary to draw aside the tendon of the flexor

ulnaris muscle, T.



The radial artery, A, Plate 18, passes external to the radial border of

the wrist, beneath the extensor tendons, B, of the thumb; and after

winding round the head of the metacarpal bone of the thumb, as seen at

E, Plate 19, forms the deep palmar arch E, Plate 18. This deep palmar

arch lies close upon the forepart of the carpo-metacarpal joints; it

sends off branches to supply the deeply situated muscles, and other

structures of the palm; and from it are also derived other branches,

which pierce the interosseal spaces, and appear on the back of the hand,

Plate 19. The deep palmar arch, E, Plate 18, inosculates with a branch

of the ulnar artery, I, Plate 18, whilst its dorsal interosseal

branches, Plate 19, communicate freely with the dorsal carpal arch,

which is formed by a branch of the radial artery E, Plate 19, and the

terminal branch of the posterior interosseous vessel.



The ulnar artery, C, Plate 17, holds a direct and superficial course,

from the ulnar border of the forearm through the wrist; and still

remains superficial in the palm, where it forms the superficial palmar

arch, F. From this arch arise three or four branches of considerable

size, which are destined to supply the fingers. A little above the

interdigital clefts, each of these digital arteries divides into two

branches, which pass along the adjacent sides of two fingers--a mode of

distribution which also characterises the digital branches of the

median, b b, and ulnar nerves, e e. The superficial palmar arch of the

ulnar vessel anastomoses with the deep arch of the radial vessel. The

principal points of communication are, first, by the branch, (ramus

profundus,) I, Plate 18, which passes between the muscles of the little

finger to join the deep arch beneath the long flexor tendons. 2nd, by

the branch (superficialis volae) which springs from the radial artery,

A, Plate 17, and crosses the muscles of the ball of the thumb, to join

the terminal branch of the superficial arch, F, Plate 17. 3rd, by

another terminal branch of the superficial arch, which joins the

arteries of the thumb, derived from the radial vessel, as seen at e,

Plate 18.



The frequent anastomosis thus seen to take place between the branches of

the radial, the ulnar, and the interosseous arteries in the hand, should

be carefully borne in mind by the surgeon. The continuity of the three

vessels by anastomosis, renders it very difficult to arrest a

haemorrhage occasioned by a wound of either of them. It will be at once

seen, that when a haemorrhage takes place from any of these larger

vessels of the hand, the bleeding will not be commanded by the

application of a ligature to either the radial, the ulnar, or the

interosseous arteries in the forearm; and for this plain reason, viz.,

that though in the arm these arteries are separate, in the hand their

communication renders them as one.



If a haemorrhage therefore take place from either of the palmar vessels,

it will not be sufficient to place a ligature around the radial or the

ulnar artery singly, for if F, Plate 17, bleeds, and in order to arrest

that bleeding we tie the vessel C, Plate 17, still the vessel F will

continue to bleed, in consequence of its communication with the vessel

E, Plate 18, by the branch 1, Plate 18, and other branches above

mentioned. If E, Plate 18, bleeds, a ligature applied to the vessel A,

Plate 18, will not stop the flow of blood, because of the fact that E

anastomoses with G, by the branch I and other branches, as seen in

Plates 17 and 19.



Any considerable haemorrhage, therefore, which may be caused by a wound

of the superficial or deep palmar arches, or their branches, and which

we are unable to arrest by compression, applied directly to the patent

orifices of the vessel, will in general require that a ligature be

applied to both the radial and ulnar arteries at the wrist; and it

occasionally happens that even this proceeding will not stop the flow of

blood, for the interosseous arteries, which also communicate with the

vessels of the hand, may still maintain the current of circulation

through them. These interosseous arteries being branches of the ulnar

artery, and being given off from the vessel at the bend of the elbow, if

the bleeding be still kept up from the vessel wounded in the hand, after

the ligature of the ulnar and radial arteries is accomplished, are in

all probability the channels of communication, and in this case the

brachial artery must be tied. A consideration of the above mentioned

facts, proper to the normal distribution of the vessels of the upper

extremity, will explain to the practitioner the cause of the difficulty

which occasionally presents itself, as to the arrest of haemorrhage from

the vessels of the hand. In addition to these facts he will do well to

remember some other arrangements of these vessels, which are liable to

occur; and upon these I shall offer a few observations.



While I view the normal disposition of the arteries of the arm as a

whole, (and this view of the whole great fact is no doubt necessary, if

we would take within the span and compass of the reason, all the lesser

facts of which the whole is inclusive,) I find that as one main vessel

(the brachial) divides into three lesser branches, (the ulnar, radial

and interosseous,) so, therefore, when either of these three supplies

the haemorrhage, and any difficulty arises preventing our having access

at once to the open orifices of the wounded vessel, we can command the

flow of blood by applying a ligature to the main trunk--the brachial. If

this measure fail to command the bleeding, then we may conclude that the

wounded vessel (whichever it happen to be, whether the radial, the

ulnar, or the interosseous) arises from the brachial artery, higher up

in the arm than that place whereat we applied the ligature. To this

variety as to the place of origin, the ulnar, radial, and interosseous

arteries are individually liable.



Again, as the single brachial artery divides into the three arteries of

the forearm, and as these latter again unite into what may (practically

speaking) be termed a single vessel in the hand, in consequence of their

anastomosis, so it is obvious that in order to command a bleeding from

any of the palmar arteries, we should apply a ligature upon each of the

vessels of the forearm, or upon the single main vessel in the arm. When

the former proceeding fails, we have recourse to the latter, and when

this latter fails (for fail it will, sometimes,) we then reasonably

arrive at the conclusion that some one of the three vessels of the

forearm, springs higher up than the place of the ligature on the main

brachial vessel.



But however varied as to the normal locality of their origin, at the

bend of the elbow, these vessels of the forearm may at times manifest

themselves, still one point is quite fixed and certain, viz., that they

communicate with each other in the hand. Hence, therefore, it becomes

evident, that in order to command, at once and effectually, a bleeding,

either from the palmar arteries, or those of the forearm, we attain to a

more sure and successful result, the nearer we approach the

fountain-head and place a ligature on it--the brachial artery. It is

true that to stop the circulation through the main vessel of the limb,

is always attended with danger, and that such a proceeding is never to

be adopted but as the lesser one of two great hazards. It is also true

that to tie the main brachial artery for a haemorrhage of anyone of its

terminal branches, may be doing too much, while a milder course may

serve; or else that even our tying the brachial may not suffice, owing

to a high distribution of the vessels of the arm, in the axilla, above

the place of the ligature. Thus doubt as to the safest measure, viz.,

that which is sufficient and no more, enveils the proper place whereat

to apply a ligature on the principal vessel; but whatever be the doubt

as to this particular, there can be none attending the following rule of

conduct, viz., that in all cases of haemorrhage, caused by wounds of the

vessels of the upper limb, we should, if at all practicable, endeavour

to stop the flow of blood from the divided vessels in the wound itself,

by ligature or otherwise; and both ends of the divided vessel require to

be tied. Whenever this may be done, we need not trouble ourselves

concerning the anomaly in vascular distribution.



The superficial palmar arch, F, Plate 17, lies beneath the dense palmar

fascia; and whenever matter happens to be pent up by this fascia, and it

is necessary that an opening be made for its exit, the incision should

be conducted at a distance from the locality of the vessel. When matter

forms beneath the palmar fascia, it is liable, owing to the unyielding

nature of this fibrous structure, to burrow upwards into the forearm,

beneath the annular ligament D, Plates 17 and 18. All deep incisions

made in the median line of the forepart of the wrist are liable to wound

the median nerve B, Plate 17. When the thumb, together with its

metacarpal bone, is being amputated, the radial artery E, Plate 19,

which winds round near the head of that bone, may be wounded. It is

possible, by careful dissection, to perform this operation without

dividing the radial vessel.





DESCRIPTION OF PLATES 17, 18, & 19.



PLATE 17.



A. Radial artery.



B. Median nerve; b b b b, its branches to the thumb and fingers.



C. Ulnar artery, forming F, the superficial palmar arch.



D. Ulnar nerve; E e e, its continuation branching to the little and ring

fingers, &c.



G. Pisiform bone.



H. Abductor muscle of the little finger.



I. Tendon of flexor carpi radialis muscle.



K. Opponens pollicis muscle.



L. Flexor brevis muscle of the little finger.



M. Flexor brevis pollicis muscle.



N. Abductor pollicis muscle.



OOOO. Lumbricales muscles.



P P P P. Tendons of the flexor digitorum sublimis muscle.



Q. Tendon of the flexor longus pollicis muscle.



R. Tendon of extensor metacarpi pollicis.



S. Tendons of extensor digitorum sublimis; P P P, their digital

prolongations.



T. Tendon of flexor carpi ulnaris.



U. Union of the digital arteries at the tip of the finger.


















PLATE 18.



A. Radial artery.



B. Tendons of the extensors of the thumb.



C. Tendon of extensor carpi radialis.



D. Annular ligament.



E. Deep palmar arch, formed by radial artery giving off e, the artery of

the thumb.



F. Pisiform bone.



G. Ulnar artery, giving off the branch I to join the deep palmar arch E

of the radial artery.



H. Ulnar nerve; h, superficial branches given to the fingers. Its deep

palmar branch is seen lying on the interosseous muscles, M M.



K. Abductor minimi digiti.



L. Flexor brevis minimi digiti.



M. Palmar interosseal muscles.



N. Tendons of flexor digitorum sublimis and profundus, and the

lumbricales muscles cut and turned down.



O. Tendon of flexor pollicis longus.



P. Carpal end of the metacarpal bone of the thumb.


















PLATE 19.

AAA. Tendons of extensor digitorum communis; A*, tendon overlying that

of the indicator muscle.



B. Dorsal part of the annular ligament.



C. End of the radial nerve distributed over the back of the hand, to two

of the fingers and the thumb.



D. Dorsal branch of the ulnar nerve supplying the back of the hand and

the three outer fingers.



E. Radial artery turning round the carpal end of the metacarpal bone of

the thumb.



F. Tendon of extensor carpi radialis brevis.



G. Tendon of extensor carpi radialis longus.



H. Tendon of third extensor of the thumb.



I. Tendon of second extensor of the thumb.



K. Tendon of extensor minimi digiti joining a tendon of extensor

communis.