ARTERY, PATHOLOGICAL CONDITIONS OF. 231 



the neighbourhood are neither distended nor liability of particular callings. It cannot be 



ruptured, and the blood within it passes through the bent positions of the limbs of such per- 



the general circulation, and of course does not sons, because many other classes, studious 



coagulate. It is difficult to class this disease persons for instance, maintain similar postures 



with aneurism in any form, yet is it termed the for a longer time and with greater frequency, 



aneurism by anastomosis. yet is not aneurism common amongst them. 



No part of the natural history of any disease Neither will the sudden stretching of the limb 

 can be more interesting than that which has by pressing the foot against the stirrup or foot- 

 reference to its causes, whether predisposing board in managing the horses throw any light 

 and remote, or immediately exciting. Cer- upon the subject, for it is found by experiment 

 tainly, when an aneurism has been formed, a that no force will rupture a healthy artery short 

 knowledge of the circumstances that occa- of what would also tear asunder the ligaments 

 sioned it will not be very useful in contributing of the adjacent joints. Allowing, therefore, 

 to its removal, although it may often assist in the accuracy and truth of these observations, 

 forming a prognosis as to the result of an their explanation is still to be sought for. 

 operation : yet if it can be made available in Some have supposed that old age, and the 

 the prevention of the disease, it must prove of deposit of earthy material which is formed in 

 no inconsiderable value. It is admitted that the arteries at that period, are predisposing 

 aneurism frequently appears suddenly as the causes of aneurism ; yet, if this was the case, 

 result of a blow, a strain, or some violent exer- the disease should be very prevalent indeed 

 tion, the patient being conscious of something among those advanced in life, whereas it is 

 having torn or given way within him. With in reality almost as rare as in infancy or early 

 still greater frequency it occurs without any youth. Of fifteen cases of large aneurism 

 such consciousness on the part of the sufferer, operated on, only two had exceeded the age 

 and persons have borne this formidable disease of forty years, the average of all being but 

 about them for months, and even for years, thirty-one and a half ; and if a larger number 

 not only without being themselves aware of its of cases (inclusive of the internal forms of the 

 existence, but, if situated internally, without disease) were collected and compared, it would 

 its being recognized by their professional at- probably be shewn to be considerably less, 

 tendants;* and it often happens that a patient With respect to the earthy deposit alluded to, 

 complains of the crookening of the fingers or it is found between the fibrous and internal 

 the numbness of the foot, unmindful of the coats closely adhering to the latter, from which 

 tumour under the clavicle or in the popliteal it can scarcely be separated : it is disposed in 

 space. Without denying that an artery, in a thin laminee or plates of different sizes, the 

 perfectly healthy condition, can become the largest being seldom greater than a spangle, 

 seat of aneurism, because there are too many and these earthy spots are distinct and separate, 

 facts apparently in support of such an opinion, not running into or connected with each other, 

 it may be remarked that if such was generally and never encircling the vessel with an un- 

 or even frequently the case, the disease ought to interrupted bony ring. They are supposed to 

 be much more common amongst the labouring render an artery friable and brittle, and there- 

 poor, and also that it should prevail amongst fore to predispose to aneurism, and have been 

 some particular trades. These considerations considered by some to be the products of 

 lead to a belief, that previous to the occurrence arterial inflammation. Unfortunately the origin 

 of spontaneous aneurism, the artery has under- and progress of this earthy degeneration have 

 gone some change predisposing to it, although not yet been satisfactorily traced. Scarpa* 

 it may not be so easy to point out the nature seems to regard it as arising from the same 

 of that change, or the causes that lead to its cause that produces the steatomatous deposit, 

 production. and states that it cannot be said to be proper 



It is observed that aneurism is of far less to old age, as it is sometimes met with in 

 frequent occurrence in woman than in man ; patients who are not much advanced in life. I 

 a comparison between the numbers of internal have seen these earthy depositions in the aorta 

 cases proving this fact in a remarkable manner, of a female not twenty-five years of age, which 

 and in cases of external aneurism still more so. was also highly inflamed and covered with 

 It is very rare to meet with a popliteal aneu- spots of soft steatomatous deposit, but still 

 rism in a female. Certainly, the more labo- that is far from proof of its being the product 

 rious habits and constant exposure to accident of active inflammation, or of its rendering the 

 in the one sex may in some respects serve to artery weak or disposed to aneurism, 

 account for this circumstance, but to those Of any number of subjects above the age 

 who know that in many places women are of sixty brought into a dissecting-room, three- 

 obliged to undergo at least as much hardship fourths will be found with this earthy dege- 

 and fatigue, the explanation will be far from neration in some of the arteries, yet the in- 

 satisfactory. Again, it has been stated that frequency of aneurism amongst old patients 

 certain pursuits of life predispose to aneurism, has been already remarked. Again, this de- 

 inasmuch as it prevails amongst coachmen and posit has been seen in the sac of a true aneu- 

 postilions, but there never has been even a rism, a circumstance that would shew it did 

 plausible reason offered to explain this greater not greatly interfere with the distensibility of 



the arterial tunics or render them more friable, 



* A very curious case of this description is related 



in the Dublin Hospital Reports, vol. v. p. 167. * On Aneurism, page 90. t 



