GEN. I. SPEC. VI. Entasia Analogies. of remote organs when united in a common chain of many instances, become the chief seat of distress, and even of danger. We had occasion to notice this law of the animal economy when treating of PARAPSIS ILLUSORIA, Trismus. Locked-jaw. or that imaginary sense of feeling and of acute pain in a limb that has been amputated and is no longer a part of Sympathy the body, which we referred to the principle before us: and farther noticed, by way of illustration, the pain often suffered at the glans penis from the mechanical irritation of the neck of the bladder by a calculus. So, irritating action. the fauces with a feather excites the stomach, and even the diaphragm, to a spasmodic action, and the contents of the organ are rejected. Irritating the ileum, as in ileac passion, produces the same effect upon the stomach and esophagus; at the same time that the other extremity of the canal is attacked with rigid spasm, and consequently with obstinate costiveness: while in cholera both extremities are affected in a like way, and we have hence both purging and vomiting. It is to the same principle we are to ascribe it that when the surface of the body is suddenly chilled, as on plunging into a cold-bath, the sphincter of the bladder becomes irritated, and evacuates the contained urine: and, in treating of MARASMUS, we had occasion to show that while, in one of its species, the disease seems to commence in the digestive, and in another in the assimilating organs, constituting the extreme ends of a very long and complicated chain of action, it very generally happens that at which end soever the decay commences the opposite end is very soon affected equally. a chain of fibres; and evinced chiefly in their remote In a continued chain of nervous fibres, however, this Sympathy pervading principle of sympathy which induces remote parts, and particularly remote extremities, to associate in the same nervous morbid action, is peculiarly conspicuous. Hence, if a long muscle be lacerated in any part of its belly the tendinous terminations are often the chief seat of suffering. As the ulnar nerve sends off twiggs from the elbow to supply the fore-arm and fingers, a blow on the internal condyle of the humerus gives a tremulous sensation through the fore-arm and hand: and as the ulnar nerve itself is only an offset from a plexus or commissure of extremities. Illustrated. GEN. I. SPEC. VI. Entasia Trismus. the cervical nerves which also give a large branch to the scapula, a paralysis of the ring or little finger has sometimes been removed by stimulating the scapular extremity Locked-jaw. by a caustic applied at the internal angle of the scapula. In inflammation of the liver, a severe pain is often felt at the top of the shoulder, and in palpitation of the heart, at the left orifice of the stomach. Both these are to be accounted for by recollecting that the radiations of the phrenic nerve extend in an upper line to the shoulder, and in a lower to the diaphragm, which constitute its extreme points; and that one of its branches passes over the apex of the heart. Now as the under surface of the diaphragm participates, from its contiguity, in an inflammation of the liver, the top of the shoulder suffers, as forming the extreme point of the phrenic chain by which these organs are connected; and as the upper surface of the diaphragm is in direct contact with the left and very sensible orifice of the stomach, an uneasiness at the apex of the heart becomes the cause of irritation to this orifice in consequence of its connexion with the diaphragm, and hence, of necessity, with the lower branch of the phrenic nerve at its extreme distribution. This reasoning applied to trismus and diseases of a like kind. Illustrated in trismus. These remarks apply with particular force to the disease before us, and many others of the same class with which it has a close analogy, as tetanus, lyssa, and hemicrania. And, although from the intricacy of the intersections and decussations with which various nerves pursue their radiating courses, it is impossible for us, in many instances, to determine why one line of connexion suffers while another remains unaffected, yet in most instances we may be able, by an accurate survey, to trace the catenation, and hence to obtain some insight into the physiology of these exquisitely curious, and complicated disorders. In mapping the nervous ramifications which give rise to trismus or locked-jaw, we must regard the ganglionic system, consisting of the various branches of the intercostal trunk, and the numerous branches which unite with it from the whole line of the spinal marrow, as constituting GEN. I. SPEC. VI. Illustration applied to the first va the centre; and as, from this centre, we perceive ramifications radiating in every direction to the face, the entire Entasia length of the back, the upper and lower limbs, and the Trismus. Locked-jaw. thoracic and abdominal viscera, we see a foundation laid even by a continuous chain, for an association of remote parts and even extreme points in morbid changes, even though we may not be able, satisfactorily perhaps, in any instance, to trace out the individual line by which the diseased action is carried forward, and to separate it from other lines with which it is inextricably interwoven. Thus, in the case of trismus nascentium, forming the first variety under the present species, the irritation of the nerves of the stomach, which is very clearly the primary seat of riety. disease in most cases, is propagated directly to the central branches of the ganglionic system, by the tributary offsets which the stomach receives from it. But we have already observed, that the chief contribution to this grand junction-canal is derived from the intercostal nerve itself, in the first instance an arm from the trigeminus or fifth pair of nerves, two branches of which radiate upwards, constitute the maxillaris superior and maxillaris inferior, and are lost in the muscles of the jaws: so that the upper extremity of the nervous line distributed over the stomach is the nerves of the jaws themselves. While various branches of the fifth occasionally unite with the portio dura, or respiratory trunk of the seventh pair, which divaricates not only to the diaphragm, but over all the muscles that have the remotest connexion with the respiratory system. And hence, agreeably to the law of the animal economy we have just pointed out, the muscles of the jaws, forming this extremity in the chain of morbid action, are the organs in which we may expect an irritation of the nerves of the stomach in various instances to manifest itself most strikingly. applied to the second In like manner we may account for the second and Illustration third varieties of trismus, or that produced by a chilly dampness, or irritative violence applied to the upper or lower extremities: for as these are all supplied by nerves and third varieties. GEN. I. Entasia from the vertebral source, which, as we have already remarked, gives off branches from every aperture in the spine to the ganglionic system, and as this system, at its upper end, terminates in the maxillary branches of the fifth pair of nerves, the muscles into which these nerves are distributed constitute one extreme point of a long chain of nervous action, while those of the upper and lower limbs constitute the other. And hence the same law which produces a spastic fixation of these muscles in certain irritations of the stomach, may reasonably be expected to operate with a like effect in certain irritations. of the upper and lower limbs. And as the intercostal nerve, at its first rise from the common source of itself and the maxillary branches, receives also, in its progress, offsets from the sixth, seventh, eighth, and ninth pairs of cerebral nerves, as well as from all the vertebral, and as all these, in consequence of such an interunion and decussation, are sending forth branches over the muscles of the back, the chest, and the thorax, there is no difficulty in conceiving, when a rigid spasm has once commenced in the lower jaw, why it should be propagated through any of the muscles appertaining to these parts of the system, or even originate in them from any of the causes that excite Illustration locked-jaw, and hence lay a foundation for tetanus as well equally apas trismus, both as a primary and a secondary disease. And I have touched upon this subject now that we may not have to repeat the present explanation when treating of tetanus in its proper place*. plicable to tetanus. In the simplest state of trismus, indeed, there is some degree of stiffness found at the back of the neck, and even in the sternum. The disease, in some cases, shows itself with sudden violence, but more usually advances gradually till at length the muscles that pull up the jaw become so rigid, and set the teeth so closely together that they do not admit of the smallest opening. : See Cloquet, Traité d'Anatomie Descriptive. Bork Beschreibung des fuensten Nervenpaares und seiner Verbindungen mit anderen Nerven, vorzuegliet mit dem Ganglienysteme. Leips. 1817. GEN. I. SPEC. VI. tium. of infancy. Peculiarly tropical cli common to mates. Called vul garly, but absurdly, Falling of In tropical climates, for Dr. Cullen's remark that it is most common to the middle-aged only applies to the tem- E. Trisperate regions of Europe, children are particularly subject mus nascento this complaint, and with a few peculiarities which, Locked-jaw though producing no specific difference, are sufficient to establish a variety. The disease in this case is vulgarly known by the absurd name of FALLING OF THE JAW. It occurs chiefly between the ninth and fourteenth day from birth; seldom after the latter period. Without any febrile accession, and often without any perceptible cause whatever, the infant sinks into an unnatural weariness, and the jaw. drowsiness, attended with frequent yawnings, and with a Description. difficulty, at first slight, of moving the lower jaw; which last symptom takes place in some instances sooner, in others later. Even while the infant is yet able to open its mouth there is, occasionally, an inability to suck or swallow. By degrees the lower jaw becomes rigid, and totally resists the introduction of food. There is no painful sensation; but the skin assumes a yellow hue, the eyes appear dull, the spasms often extend over the body, and in two or three days the disease proves mortal. cause. The ordinary cause is irritation in the intestinal canal. Ordinary Hence viscid and acrimonious meconium frequently produces it; as worms are said also to do, some months after birth. It seems, moreover, in some instances, to have followed from irritation in tying the navel-string, or its not being properly attended to afterwards: in which case, though the stomach may be affected by contiguous sympathy, the disease makes a near approach to the third or traumatic variety. Yet the appearance of the spastic action is as early as where the stomach is primarily affected. Disease sometimes found in cold In cold and even mountainous counties this variety is also sometimes found. "I am informed", says Dr. Cullen, "of its frequently occurring in the Highlands of and mounScotland; but I never met with any instance of it in the countries. low country." 99* Whether, according to the conjecture of Loc. citat. § MCCLXXXI. tainous |