Upon this subject THOMSON observes::-"In some of the wounds in which the head had been struck obliquely by the sabre, portions of the cranium had been removed without the brain appearing to have sustained much injury. In one case of this kind, where a considerable portion of the upper part of the occipital bone along with the dura mater had been removed, a tendency to protrusion of the brain took place during an attack of inflammation; a slight degree of stupor, with loss of memory occurred: but on the inflammatory state having been subdued, the brain sunk to its former level, the stupor went off, and the memory returned. It seems probable that when the brain protrudes in cases of this kind, a disposition to the formation of fungus may be given; but in the instances which I have seen this protrusion occur, it has appeared to me to proceed from causes very different from those by which fungus is usually produced. We had frequent opportunities of seeing the upper and the lateral parts of the cerebrum exposed by sabre wounds; but in no case, except that which I have mentioned, did any tendency to protrusion of the brain present itself to our notice. In a remarkable sabre cut in the nape of the neck of a Frenchman in the Corderie, more than an inch in breadth of the inferior part of the left lobe of the cerebellum had been exposed, and was seen pulsating for a period of eight weeks, without any tendency to protrusion having taken place. This exposure was unaccompanied by any particular constitutional affection; but, like several others who had received deep cuts on the back part of the neck, this man complained of great feebleness in the lower extremities." (pp. 50, 1.)]

390. Fractures of the Skull (Fracture Cranii) vary, according as the separation of the bones is slight or the edges are wider apart; in the former case they are called Clefts or Fissures (Fissure.) These may penetrate either only through the external table, or also through the inner; or the inner table alone may have sprung off. Their direction is various; straight, jagged, or sometimes both at once, and so on. They occur either at the place where the external violence has acted, or far from it, and are then called Counter-Clefts (Contra-Fissure) and Counter-Fractures (Contra-Fractura.) The more brittle and fragile are the bones of the skull, the more readily do fractures occur, and because the thickness of the bones is unequal at different parts, counter-fractures are produced. Fracture of

the inner table happens only at those parts where the two tables are separated by diploë, and where the external is thicker than the internal. Fractures of the skull occur the more easily as the bones are thinner and more compact, and have less diploë; they are, therefore, most common in old, and less frequent in young persons.

[It may be observed, that no symptoms are here mentioned as indicating the existence of fissure or fracture of the skull, nor indeed are any produced from such injuries. Upon this point POTT well observes:-"The symptoms just mentioned (vomiting, giddiness, loss of sense, speech, and voluntary motion, bleeding at the ears, nose, mouth, &c.) do very frequently accompany a broken skull; but they are not produced by the breach made in the bone, nor do they indicate such breach to have been made. They proceed from an affection of the brain, or from injury done to some of the parts within the cranium, independent of any ill which the bones composing it may have sustained. They are occasioned by violence offered to the contents of the head in general; are quite independent of the mere breach made in the bone; and either do or do not accompany fracture, as such fracture may happen to be or not to be complicated with such other ills. They are frequently produced by extravasations of blood or serum, upon or between the membranes of the brain, or by shocks or concussions of its substance, in cases where the skull is perfectly intire and unhurt. On the other hand, the bones of the skull are sometimes cracked, broken, nay, even depressed, and the patient suffers none of these symptoms. In short, as the breach made in the bone is not, nor can be, the cause of such complaints, they ought not to be attributed to it, and that for reasons which are by no means merely speculative." (pp. 132, 33.)]

391. If in fracture of the skull, its coverings be not injured, and the edges of the fracture be not separated, the fracture cannot be discovered by the touch; it frequently can only, with more or less probability, be presumed, according to the violence with which the force has operated.

If there be a wound and the bone be bared, the cleft is distinguishable, as most commonly blood oozes out of it, when it has been sponged, which distinguishes it from the natural grooves in the bones of the skull; also if the pericranium over the cleft and fracture be separated, the irregularities may be perceived with the finger and with the probe, and with a very thin probe the depth of the fracture may be measured. Bleeding from the nose, mouth, and ears, are not always decided signs of fracture of the skull (1). A knowledge of counter-fractures is quite uncertain; only when extensive can they, perhaps, be traced through the external coverings, or if these be changed in appearance, they may be suspected (2).

[(1) Bleeding from the ears, in injury of the head, is of not unfrequent occurrence, and although generally accompanying fracture through the base of the skull, is not always present; and when it occurs, it is not to be considered as a decided mark of that fracture; at least a patient may recover, with few or without any symptoms of injury to the head, when it takes place even to the extent of a pint of blood; an instance of which I have had under my care within the last three or four years. It is, however, a symptom not to be thought little of, as it so frequently accompanies serious mischief. Bleeding from the mouth, in fractured base of the skull, is rare; I have not seen it above two or three times.

(2) I am not aware of a single instance in which it could be certainly determined prior to death that a fissure at the base existed; but I have known frequent examples of its presumed existence being disproved on examination of the head after death, as well as many in which it was found when not anticipated.-J. F. S.]

392. Every fracture of the skull proves that it has suffered severe violence. The external appearance of injury to the bone is not always proportionate to its danger; as, from the condition of the external wound of the bone, the internal state of the parts cannot be decided on. The peculiar brittleness and glass-like state of the internal table of the skull, is the cause of its not breaking in the direction and to the extent of the external fracture, but that the fracture always radiates, that it most commonly splits, and that the dura mater is thereby more or less separated and injured. The violence most commonly causes bruising of the diploë, and other changes in the interior of the skull. On these grounds, it is held that in most cases, clefts and fractures of the skull may produce, either at once or at a shorter or longer period after the injury, irritation of the membranes of the brain, and of the brain itself, extravasation of blood or pus, and destruction of the bone; and that, therefore, fractures of the skull and penetrating clefts require trepanning, although no symptoms of pressure or of irritation of the brain be present. If clefts and fractures of the skull be considered as conditions free from danger, and if trepanning be restricted merely to those cases in which, with other accompanying injuries, symptoms of irritation and pressure of the brain occur at once, or come on later, so, in most cases, the result will be unsatisfactory if the trepanning be delayed till the consecutive symptoms have occurred, as the diseased changes within the skull will have already advanced to a considerable extent.

[GUTHRIE makes some very good remarks on fracture of the internal table of the skull, resulting from the blow of a sword, hatchet, or other clean-cutting instrument. "When the sword or axe” says he," has penetrated as far as, or through the internal table, the case is of a much more serious nature, for this part will be broken almost always to a greater extent than the outer table, and will be separated from it and driven into the membranes, if not into the substance of the brain itself; the surface of the bone showing merely a separation of the edges of the cut made into it. These cases should be all carefully examined. The length of the wound on the top or side, or any part of the head which is curved and not flat, will readily show to what depth the sword or axe

has penetrated. A blunt or flat-ended probe should in such cases be carefully passed into the wound, and being gently pressed against one of the cut edges of the bone, its thickness may be measured, and the presence or absence of the inner table may thus be ascertained. If it should be separated from the diploë, the continued but careful insertion of the probe will detect it deeper in the wound; a further careful investigation will show the extent in length of this separation, although not in width; and will in all probability satisfy the surgeon that those portions of bone which have thus been broken and driven in, are sticking in or irritating the brain. In many such cases there has not been more than a momentary stunning felt by the patient; he says he is free from symptoms, that he is not much hurt, and is satisfied he shall be well in a few days." (p. 86.)]

393. According to the result of close observation and experience, the dangers of clefts and fractures of the skull are in this respect exaggerated. They are very different, according to the degree of violence by which they are produced, according to the condition of the bones of the skull and the other injuries and affections of the brain which may be connected with them. They frequently occur as simple injuries of bone, without splintering or separation of the dura mater, without further and irregular radiation of the internal table, and they heal by simple treatment of the wound and strict antiphlogistic remedies, repeated blood-letting, purgatives, and cold applications. It is therefore not advisable, with the mere object of discovering some cleft or fracture of the skull, to cut into the soft parts, if no other circumstances require it. If the fracture of the skull be accompanied with much splintering, as in starred fractures and so on, and the splinters which irritate and injure the dura mater cannot be removed, or if symptoms of extravasation and pressure of the brain be present, and the edges of the bone be so close that the extravasation cannot escape, then trepanning is requisite.

[CHELIUS's views on this important point are extremely correct; it is quite time enough to make cuts through the scalp and trephine the skull when symptoms have occurred: it should never be thought of otherwise. The less done as regards meddling with fractures of the skull, the better; they never should be interfered with except compression be present.-J. F. S.]

394. If in fracture of the skull one edge of the bone sink inwards, it is called Fracture of the Skull with impression (Fractura Cranii cum impressione.) In indented skull-bones, especially in children, indentation is possible without fracture (1); just as in persons of middle age, the external table may be pressed into the diploë without fracture of the internal table (2). The indentation is always discoverable by the touch, and with careful examination can always be distinguished from the bump with a hard edge (3). Often a whole piece of the skull is broken off and depressed; often is there a starred fracture; often the external table is still whole, and the internal sprung.

Indentations of the skull are nearly always accompanied with severe injury of its coverings, with separation of the dura mater, injury of the vessels, and extravasation. The effects of indentation of the skull are symptoms of pressure on the brain, inflammation of the brain and its membranes. In rare cases, however, even severe indentations are at first unconnected with any bad symptoms; those of pressure and irritation come on at a later period.

[(1) The extent to which the skull may be indented in children, without symptoms of compression, is almost incredible. I remember a case under my friend GREEN some years ago, in which a child, about three or four years old, had the skull indented, near the upper part of the lambdoidal suture, so deeply that the bowl of a dessert spoon would easily lie in it. The child had no symptoms of pressure: little more was done

than keeping it quiet and looking after its bowels; it never had a symptom; left the house perfectly well, but with the skull indented as at first.

(2) ASTLEY COOPER speaks of a "curious fracture of the skull which occasionally happens over the frontal sinuses. When the fracture is simple, if the nose be blown, the air escapes through the opening in the bone into the cellular membrane under the skin, and renders the forehead emphysematous. If, on the other hand, the fracture be compound, upon blowing the nose the air rushes through the wound, so that, in either case the nature of the accident may be easily ascertained." (p. 296.) This is a very rare accident. I have only once seen an instance of a simple one, and in this the air made its way into the cellular tissue beneath the upper eyelids and closed them. No dangerous consequences followed the injury.

(3) Care must be taken, especially by young practitioners, in deciding on the existence of fracture with depression, when there is no external wound, as the depression is often only seeming and not real. Upon this point ASTLEY COOPER observes:-"A person receives a blow on the scalp; the parts immediately surrounding the spot where the blow was received swell from the extravasation of blood; but at the part on which the blow directly fell, the cellular membrane, having been condensed by the injury, will not receive the extravasated blood; thus the surrounding parts are considerably higher than the middle." (p. 301.) The exact state of the case can, however, be ascer tained without much difficulty, if the seeming depression originate from the cause just mentioned; firm pressure on the elevated part for a few minutes will diffuse the outpoured blood into the surrounding cellular tissue, and the apparent depression will disappear; but if there be actual depression, the pressure of course will not make any alteration in the hollow formed by the driving down of the bone.-J.F.S.]

395. Fractures with impression of the skull always require immediate trepanning, although unaccompanied with symptoms of pressure and irritation of the brain. These occur earlier or later, and then no benefit is derived from the operation The object of trepanning is to raise the inpressed bone, to remove the extravasation and the splinters of bone, and to prevent aftercollections in the cavity of the skull. Trepanning is only superfluous when, from the condition of the wound, it is possible to remove carefully the splinters or completely broken-off pieces, and to let the extravasation escape. It may be hoped in children who have fracture with impression, that with proper antiphlogistic curative means, nature will accommodate the brain to the pressure, if the indent be not upon a blood sinus, in which case it must be at once trepanned.

[CHELIUS does not appear to make any difference in the treatment of simple fracture with depression, and of that which is compound or accompanied with wound of the scalp; but in both cases, whether symptoms of pressure on the brain do or do not exist, immediately proceeds to trephine, and removes the depressed bone. The cases, however, require different treatment if the fracture be simple, but if compound the same practice is proper for both. If the fracture be simple and unaccompanied with symptoms of pressure, no incision is to be made through the scalp upon it, and much less should it be trephined. ASTLEY COOPER observes on this point:-"If the fracture be simple and there be no wound in the scalp, and no symptom of injury to the brain, it would be wrong to make an incision into the part, and perform the operation of trephining; for, by making such an incision, you add greatly to the danger of the patient, as you may make what was before a simple, a compound fracture, and consequently greatly increase the danger of inflammation, which rarely follows fracture with depression, where the fracture is simple, but is a very frequent consequence of a compound fracture, which is produced by making an incision in the scalp. Never make an incision therefore when you can avoid it, or merely because there is a fracture with depression, if there be no symptoms of injury to the brain. Even if there be symptoms of injury to the brain, and the fracture be simple, do not immediately trepan. Take away blood and purge your patient freely, and see how far the symptoms may be the result of concussion of the brain, and not of depression. If the symptoms do not yield to depletion, then, and not till then, perform the operation of trephining." (pp. 303, 304.)

ABERNETHY also holds the same opinion. "It appears very clearly," says he, "that a slight degree of pressure does not derange the functions of the brain for a limited time after its application. That it does not do so at first is very obvious, as persons are

often perfectly sensible and free from headach and giddiness immediately after the injury. Whether it may not produce such an effect at some remote period, is not so easily determined, since this cannot be ascertained but by a continued acquaintance with the persons who had received the injuries. All, however, whom I have had an opportunity of knowing for any length of time after the accident continued as well as if nothing of the kind had ever happened to them. (p. 14.) Though a slight degree of pressure does not immediately affect the functions of the brain, yet it may act in another way; it may excite inflammation of that organ, as it does of other parts of the body. Its power in this respect, however, will probably lessen by the part becoming accustomed to it; and the cases on record, where fractures with depression have done well, as well as those of recovery from apoplexy, are proofs that the cause which in the first instance was injurious by its pressure may continue to exist without inconvenience. Such cases ought surely to deter surgeons from elevating the bone, in every instance of slight depression, since by the operation they must inflict a further injury upon their patients, the consequence of which it is impossible to estimate. From all therefore I have learned from books, as well as from the observations I have made in practice, and from reasoning upon the subject, I am disposed to join in opinion with those surgeons who are against trephining in slight depressions of the skull, or small extravasations on the dura mater. *** A circumstance, however, frequently occurs that may render the surgeon doubtful as to what course he ought to pursue; this happens, when at the same time that the skull is slighly depressed, the patient labours under the effects of concussion. *** As the effects of the latter gradually abate, a little delay will enable the surgeon to decide upon the nature of the mischief, and take his measures accordingly. Where the patient retains his faculties, nothing farther is necessary than a continuance of the antiphlogistic plan; and should any inflammation afterwards take place, the same means employed, in a degree proportioned to the urgency of the symptoms, will, in most instances, be successful, without elevating the bone." (p. 21-23.)

It must not, however, be forgotten, that, although to the teaching of these two great masters in Surgery, the almost universal practice, now pursued in this country, of not trephining simple fractures of the skull, with depression but without symptoms, must be ascribed, yet the practice did not originate with them: for DEASE appears to me to have been the first, who, led by the result of his own observations, broke through the practice of trephining in cases of simple fracture of the skull, for fear of inflammation and suppuration of the dura mater, especially laid down by POTT, whose practice he for some time followed. In his Introduction he says:-"I considered those fatal consequences too often to proceed from the obstinacy of the patients in not submitting early to the necessary evacuations, and their general neglect of keeping to any low regimen; as the greater number by far of them were under no apprehension of danger, from a wound unattended by any other disagreeable circumstance, so that until they were seized with those symptoms which shewed the suppuration begun, they, for the most part, followed their usual employments. I determined, therefore, to persuade such as presented themselves, especially those who had wounds where the cranium was so injured as to make me apprehend the dura mater or its vessels suffered, as in those who had simple fractures, to come into the hospital, informing them of the bad consequences their not complying would be productive of. All those who fell under my care, in such circumstances, from the beginning, I treated in the manner I then thought most likely to prevent any future inflammation and suppuration taking place in the brain or its meninges; profuse bleeding, purging, severe regimen, &c., were not spared; and all those who had simple fractures were immediately trepanned. However, I can assure the reader, the event by no means answered my expectation; for, notwithstanding, fevers, shiverings, and all the concomitant symptoms of matter underneath the cranium, succeeded as frequently in ten, twelve, or fourteen days, and terminated as fatally as if they were entirely left to nature; and such as recovered I could by no means attribute to the treatment, as many in similar circumstances did well, without having the least alarming symptoms intervene, although they neglected all advice, and some lived very irregularly; and even in such as were after seized with symptoms they did not appear earlier or more severe, than in those who were treated with the most exact attention.

"From this I am induced to think that a surgeon who applies the trepan in simple fractures, where he has not a strong probability of the detachment of the dura mater, extravasation, &c., in order to obviate the consequences of its future inflammation and suppuration, subjects his patient to a severe operation, ever more or less dangerous in itself, often productive of disagreeable effects, which remain during life, and by no means indicated; and that the good effects of profuse bleeding, in disengaging the parts affected, are extremely doubtful." (p. xxii-xxvi.)