Surgical Experiences in South Africa, 1899-1900. George Henry Makins
aside all the above remarks, however, I am inclined to think that a general tendency to primary union and the absence of suppuration will always be a feature of wounds from bullets of small calibre, and that this favourable tendency is attributable to certain inherent characters of the injuries. Of these the nature and small size of the openings, the dry character of the lining of the track due to superficial destruction and condensation of the tissue forming its wall, the small disposition to prolonged primary hæmorrhage, and the absence of any great amount of serous exudation during the early stages of healing are the most important.
A mechanical factor of great importance also exists in the spontaneous collapse and automatic apposition of the walls of the track. This closure is rendered additionally effective in many cases by the interruption of the continuous line in the wounded tissues consequent on alteration in the position of the parts traversed when an attitude of rest is assumed by the injured part. The indisposition to suppuration and the apparent unsuitability of the tissue lining the track for the development and spread of infecting organisms are well illustrated by several observations. Thus, even if the bullet be thoroughly aseptic, the fragments of destroyed skin driven into the track by the bullet can scarcely be free from organisms; yet these seldom give rise to trouble. Again, if for any reason a deep portion of a track becomes infected and suppurates, there is no tendency for the spread of infection along the line of wounded tissue, but rather for the development of a local abscess, pointing in the ordinary direction of least resistance, irrespective of the course originally taken by the bullet.
Mauser Wound of Entrance, a little more than 48 hours after infliction. About 12/1.
G. L. Cheatle.
Section of the entry segment of an aseptic Mauser wound removed a little over forty-eight hours after its infliction. Magnified twelve diameters.
The margins of the opening are still sloping and depressed, indicating the originally 'punched-in' nature of the aperture. A thin stratified layer of epidermis completely closes it. No scab remains.
The wound track is occluded by an effusion of lymph, commencing organisation of which is shown under a higher magnifying power by the presence of leucocytes near the margin of the bounding tissue, and some giant cells. The effusion of lymph occupies a slightly wider area immediately beneath the papillary layer of the skin, then narrows, and broadens again as the subcutaneous fascia is reached, indicating the effect of resistance in widening the area of damage.
The subcutaneous connective tissue bounding the track shows little sign of alteration beyond a general slight tendency of the lines of structure to deviate in the direction of the passage of the bullet.
No hæmorrhage is apparent beyond a small collection of blood situated immediately beneath the new layer of epidermis at the left-hand corner of the opening.
Range probably within 800 yards. Seat of wound, abdominal wall a highest point of iliac crest.
Fig. 25 (a), a (plate I.) represents a section carried across an aseptic aperture of entry. The specimen was removed by Mr. Cheatle from a patient who died forty-eight hours after reception of the injury. It shows well the small amount of gross destruction suffered by the subcutaneous tissue, and the rapid repair which follows, since macroscopically the track is scarcely discernible. Reference to plate I. shows the remarkable fact that even at this early date considerable progress towards definite healing has occurred, and a thin layer of stratified epidermis covers the original opening. The question may be raised whether the origin of this epidermal layer is not in part a floating up of the margins of the main aperture.
During the course of healing some variation takes place in the appearance of the apertures, especially that of entry. This, at first contracted, later becomes somewhat relaxed, while in many cases a small halo of ecchymosis develops around it. The blood-clot occupying its centre now contracts, the margins rapidly become approximated centripetally, and a small circular dark spot only remains, which is later replaced by a small red cicatrix. The dark central spot under these circumstances consists of the contused margin of the wound in the skin, and a small proportion of blood-clot which finally comes away as a small dry scab. When slight local infection occurs in place of simple contraction and dry scabbing, the process is prolonged, the contused margin separates by granulation, the clot in the opening breaks down, and a small ulcer of somewhat larger proportions than the original wound remains and takes some days to heal.
A. Wound of entry 48 hours after reception. B. Wound of exit, 7½ days after reception. 1. Skin. 2. Subcutaneous fat carried into the lips of the wound by the bullet. 3. Infected blood extravasation in subcutaneous tissue. Exact size. (See plates I. and II.)
The aperture of exit in simple wounds of the soft parts sometimes heals even more rapidly than that of entry, and if of the slit form may be almost invisible at the end of ten days or a fortnight, actual primary union having taken place as after a simple small incision. Larger or irregular exit apertures, however, take a longer period to close than entry wounds, and this is most often observed when the bullet has undergone deformation within the body, or bone fragments have been driven out with the bullet.
Fig. 25 (a), b (plate II.) represents a section of an infected exit aperture from a patient who died seven and a half days after its infliction. Two main points of interest are at once apparent: 1. The carrying forwards of the subcutaneous fat into the lips of the skin wound by the bullet. This illustrates the manner in which lightly supported structures are carried forward by the bullet, and throws some light on the mode by which vessels and nerves may escape by a process of displacement. This figure may be compared with fig. 25 (b) which shows a tag of omentum similarly carried forward by a bullet crossing the abdominal cavity and plugging the exit wound. 2. The second feature of interest is the amount of hæmorrhage into the subcutaneous tissue. In this respect the contrast between the exit and entry apertures is marked, since in the latter hæmorrhage is scarcely apparent. The presence of such hæmorrhages is explained by the same dragging action as the extrusion of the fat, and is of course dependent on consequent rupture of small vessels. It is of importance as predisposing the exit wound to more easy infection, and it accounts for the persisting subcutaneous induration more often detected beneath healed exit than entry apertures. Again, it suggests that the presence of blood in the deeper parts of the tracks may be the determining cause of the indurated cords often replacing them.
G. L. Cheatle.
Mauser Wound of Exit, 7½ days after infliction. Healing delayed by Infection. About 12/1.
Section of the exit segment of a Mauser wound, removed seven and a half days after infliction. Magnified twelve diameters.
The healing process has been delayed by infection.
There is no attempt at closure by a layer of epidermis, and the margins are not depressed.
The wound track is narrower than that seen in the entry wound plate I., and completely occluded by a plug of the subcutaneous fat which has been carried forward by the bullet in its passage. A small wedge-shaped plug of lymph indicates the position of the actual track at its termination.
Dragging on the surrounding tissue consequent on the extrusion of the plug of fat has ruptured some capillaries, and given rise to considerable extravasation of blood, which is seen as a darker layer in the deepest portion of the wound.
Comparison of this plate with the exit wound depicted in fig. 16, p. 56, explains the nature of the tags of tissue there seen to protrude from the convex opening.
Range 800 yards. Seat of wound, abdominal wall below 9th costal cartilage.
Pari