which is also applicable, both to the second and last phalanges of the fingers. The operator should grasp the phalanx to be removed between his finger and thumb, and forcibly bending it, let him cut into the back of the joint in its whole extent, divide the lateral ligaments, and passing the knife beneath the bone, complete the operation by cutting a flap of sufficient size from the palmar surface of the finger: the wound in this case should be precisely the same shape as in the preceding operation. It often happens in practice that the integuments on the palmar side of the finger are insufficient of themselves to form a covering for the head of the remaining bone; in these cases either the head of the proximal phalanx may be removed with the forceps, or a small flap must be traced out and reflected from over the back of the joint. - Amputation of the phalanges of the fingers by double flaps. -The hand being placed in a position of pronation, the operator stands as in the preceding operations; he should transfix the soft parts immediately under the shaft of the phalanx, just in front of the joint at which he wishes to disarticulate, and thus cut a short flap from the palmar side of the finger. A semilunar flap of the same dimensions being traced out over the dorsum of the joint, should be reflected, the joint opened from behind, and the bone removed. Fig. 13 c shows the shape and position of the flaps for this operation. Amputation of the first, second, and third fingers at their metacarpal joints. The operator, having taken in hand the larger of the two scalpels with which he is supposed to be provided, should stand grasping the finger he is about to amputate and facing the subject; while the assistant, standing with his back turned towards the subject, should separate the contiguous fingers. The hand being pronated, let an incision be commenced on the back of the metacarpal bone, about half an inch behind its head; this must be carried along the line of the extensor tendon for half an inch, and then diverge to the operator's right hand side, and run obliquely up to the angle of the cleft between the fingers, pass across the palmar surface of the first phalanx, at the transverse mark which is found at its base, and returning to the back of the hand, should fall into the first incision just over the prominence of the knuckle (fig. 13 d). This cut should extend down to the bones in its whole extent, and if possible should divide the extensor tendon of the finger as it lies on the head of the metacarpal bone; the incision may be a continuous one, or more easily it is formed by making two separate cuts, each commencing on the back of the metacarpal bone and joining on the palmar surface of the first phalanx. The soft parts must be dissected from the posterior part of the joint, the lateral ligaments divided, while the operator puts them on the stretch, and the articulation opened by a semilunar incision with its convexity directed towards the ends of the fingers; the remaining ligamentous connections of the bone being severed, the operation will be complete. In practice, should there be insufficient integument on the finger to cover the head of the metacarpal bone, the same operation be performed, and the head of that bone removed with the cutting forceps, applied so as to divide the bone obliquely. may Amputation of the little finger at its metacarpal joint. For this, the same operation may be put in practice, except that the angle of the incision should fall over the ulnar side of the corresponding metacarpal bone (fig. 13 e). Amputation of the fingers en masse at their metacarpal joints.*—The operator, standing as in the preceding opera * The operation is here described as it should be performed on the left hand. tions, should turn up the palm of the hand as is represented in fig. 17, p. 76, and trace a convex flap, commencing and ending on the distal extremities of the metacarpal bones of the little and index fingers respectively, and extending towards the fingers as far as the transverse line seen on the palmar aspect at their roots. Turning the fingers in the opposite direction, so as to bend the knuckles and expose the back of the hand, let him make an incision commencing and ending at the extremities of the second and fifth metacarpal bones, and extending over the knuckles as far as the fork of the fingers, as seen on their dorsal aspect, thus forming a semilunar flap with its convexity turned towards the fingers and reaching just beyond the heads of the metacarpal bones (fig. 15, p. 73). Having reflected this, and opened all their joints on the dorsal aspect, let the operator completely divide the capsular ligaments, and pass the blade of the knife behind the heads of the phalanges he is about to remove; and by cutting towards the fingers, he will bring the knife out in the palm at the extremity of the flap which he first traced. Amputation through the third and fourth metacarpal bones. -This operation, though demanded in many cases of injury, is often employed in preference to the removal of the fingers at their metacarpal joints, in those cases where the appearance of the hand is a more important consideration than its strength. An incision, such as is represented in fig. 13 g, being made so that its angle is on the dorsum of the metacarpal bone, midway between its articular extremities; the integuments should be dissected from the shaft and head, proceeding from behind forwards, until the palmar surface of the bone is nearly cleared: the knife should now be thrust under the bone, and made to free its anterior surface from any remaining connections. This accomplished, the shaft of the bone should be divided obliquely with the bone forceps, so as not to leave an abrupt extremity. The foregoing operation has an advantage over the one more commonly employed, in not leaving behind it any cicatrix in the palm, and in injuring no blood vessels of any size. The position of the operator and assistant should be the same as in amputation of a finger at its metacarpal joint: a long narrow scalpel should be used. Amputation through the second and fifth metacarpal bones. These bones may be removed with greater facility than the two last mentioned, and the same operation may be used, except that the incisions must commence and end on the radial side of the second, and on the ulnar side of the fifth metacarpal bone. In using the forceps it is here especially necessary to divide the bone obliquely, and thus avoid an unsightly prominence on the side of the palm. No artery of any consequence need be wounded in any of the preceding operations; though care must be taken, in separating the second metacarpal bone from its connections, to avoid injuring the arteria radialis indicis, anywhere but at the point where it must be divided, namely, opposite the metacarpo-phalangeal articulation. Amputation of the thumb at its metacarpo-phalangeal articulation. It may save subsequent trouble and much facilitate the process of disarticulation, if the operator will turn to page 73, fig. 15, and glance at the skeleton of the hand. He will notice that the line of this articulation is much more nearly transverse than that of the same joint in the other fingers; it is situated just in front of the prominence of the knuckle, and for practical purposes may be considered to run straight across the thumb from side to side. To remove the thumb at this joint, make an incision as represented in fig. 15 b, with its angle on the subcutaneous surface of the metacarpal bone half an inch behind the head, and passing in front of the thumb just beyond the sesamoid bones. Dissect away the soft parts from the back and outer side of the joint, and open it on its posterior aspect, twisting the thumb hither and thither to facilitate the division of its ligaments. In separating the soft parts from the front of the phalanx, care should be taken lest the point of the knife be entangled in the sesamoid bones, for covering which a larger provision of soft parts must be made than was necessary in the corresponding operation on the other fingers. Amputation of the thumb at its articulation with the trapezium.-It will be well to examine this articulation before attempting to remove the bone. The articular surface of the trapezium is saddle-shaped, and so indeed is the metacarpal bone of the thumb, though in an opposite direction, and thus it is by no means easy to insinuate the point of the knife between their opposed surfaces; the exact position of the joint may, however, be ascertained by passing the forefinger down the dorsal surface of the corresponding metacarpal bone towards the wrist, until the tubercle is felt at the base of the bone which gives insertion to the extensor ossis metacarpi pollicis; immediately behind this point of bone lies the articulation in question. The operator should grasp the thumb, and stand facing the dorsum of the hand, which should be in a position between pronation and supination; the fingers should be held aside by the assistant. The point of a narrow knife must be inserted midway between the tubercle of bone above alluded to and the styloid process of the radius, and an incision be carried from this spot obliquely along the dorsum of the metacarpal bone to the ulnar side of the base of the first phalanx of the thumb*, around the palmar surface of which it must pass * In operating on the right side of the body, the incision would of course be made in the opposite direction. |