Embolism, Thrombosis, Hemorrhage, and Abscess of the Spinal Cord.
Although the spinal cord is a segment of the same central organ as the brain, nourished in a similar way, and subject to the same physiological and pathological laws, lesions of the vascular apparatus, which play so important a part in brain pathology, play a comparatively insignificant one in that of the spinal cord. Embolic, thrombic, and primary hemorrhagic lesions of the cord are so rare that their possible existence has even been denied. A primary thrombosis of the cord has not yet been satisfactorily demonstrated to occur independently of syphilitic lesions; and when it occurs the ensuing tissue-changes, as described by Heubner, Julliard, and Greiff, are usually in the background as compared to the gummatous, sclerotic, or meningitic changes which coexist. The clinical as well as the anatomical picture is accordingly either one of a myelitis or meningitis, as the cases of Charcot-Gombault, Heubner, McDowell, Wilks, Wagner, Zambaco, Homolle, Winge, Moxon, Schultze, Westphal, Julliard, and Greiff show. (See Myelitis and Spinal Meningitis.)
With regard to the occurrence of hemorrhage into the substance of the spinal cord (hæmato-myelia), it is so rare an occurrence that I can recall but a single case in which I entertained the diagnosis of this lesion; and in that very case I am unable to declare that it was not a hemorrhagic myelitis. Aneurismal changes of the spinal arteries are comparatively of rare occurrence, and as other predisposing causes to primary vascular rupture are rare in the cord, the probability of its occurrence is very much diminished. Hebold,77 in a young girl who had developed severe cerebro-spinal symptoms during a period of nine months following an erysipelatous disorder, found the upper dorsal cord, on section, dotted with numerous reddish and round points. These points corresponded to aneurismal dilatations of the vessels. As there were other inflammatory and vascular lesions in the same subject, the author referred their causation to a general constitutional vice, the result either of the phlegmonous or of a tuberculous disorder.
77 Archiv für Psychiatrie, xvi. 3. Rupture of miliary and other aneurisms in the meninges has been reported by Astley Cooper, Traube, and others. It is remarkable that such cases are more and more rarely recorded from year to year in inverse ratio to the accuracy of our spinal autopsies. I have never found a miliary aneurism below the uppermost cervical level of the cord. On the other hand, I have found extensive spinal hemorrhage in cases where the vessels of the cord proper were fairly healthy.
It is claimed that suppression of the menses, over-exertion, lifting heavy weights, and concussion are causes of spinal hemorrhage. The same causes are also mentioned for acute hemorrhagic myelitis; and it is a question whether the supposed hemorrhage is an initial lesion or secondary to congestive or anæmic softening.78
78 I have never found vascular ruptures, although carefully searching for them, in the spinal cord of persons dying instantly after falls from a great height, or, as in one case which I was fortunately able to secure the cord of, where the subject had been violently thrown down. Where hemorrhages have been found under these circumstances they were, as far as I am able to learn from the cases recorded, meningeal.
The symptoms attributed to spinal hemorrhage are the same, taking the same locality of the cord, as those of a very rapidly-developed transverse myelitis. It is unnecessary to enumerate these here in anticipation of the next section. They are described as being much more sudden. This suddenness is the only diagnostic aid on which we can rely.79 The fate of the patient is said by Erb to be decided within a few days. If he survive the immediate consequences of the hemorrhage, he is apt to recover, as to life, altogether, with such permanent atrophies, paralyses, and anæsthesias as are entailed by the destruction of the tracts and gray substance involved in the hemorrhage. The treatment recommended for this condition consists of rest, either in the lateral or prone position, local depletion and derivation to the intestinal canal, as well as the internal use of ergotin. The local application of ice, which is also advised, is probably based on illusory views.80 After the immediate danger is past the case is to be treated as one of myelitis—a very safe recommendation in view of the probability that it was a case of myelitis from the beginning.
79 And even this sign is unavailable as a distinguishing feature in supposed hemorrhage from concussion, as sudden paraplegias of motion and sensation are found in some cases of railway spine, and, although a number of cases terminating fatally have been examined, there was not always hemorrhage even in the meninges.
80 Until authorities shall have agreed as to what effect the exposure of the bodily periphery to certain temperatures has on the circulation of the cord, it would be premature to make any special recommendations as to the temperature at which they should be kept. I am inclined to believe that while, as is universally accepted, a general cooling of the bodily surface tends to increase vascular fulness in the cord, as in all other internal organs, a partial cooling, as of the feet, produces local anæmia at the level of origin of the nerves supplying the cooled part. Certainly, the bilateral neural effects of unilateral cooling are in favor of this view.
The descriptions given of the hemorrhagic foci as observed after death strengthen the view that they were in the majority of cases of myelitic origin. Usually, they are stated to extend up and down the cord in the direction of least resistance—that is, in the gray substance—resembling an ordinary apoplectic clot. But in their neighborhood there was usually considerable softening, and, to judge by the descriptions given, this softening differed in no wise from that which is the characteristic feature of acute myelitis;81 and often the transition from a peripheral zone of white softening, through an intermediate zone of red softening, to a central compact clot, is so gradual as to leave it unquestionable that the softening pre-existed, and that a vessel had broken down in the midst of the myelitic detritus. Many ancient foci of myelitis betray the hemorrhagic complication of their initial period by the presence of pigmented residue of the absorbed clot.