23 Wallace, however, found that in the Medical College Hospital at Calcutta the disease occurred proportionably more frequently in the children of European than of native mothers, though the actual number of cases among the latter was very much the greater.
Attacking usually the children of the poor, others have not been altogether exempt from it, though unquestionably “it is most often seen where the mothers of the children are very young or very poor or very worthless” (Mosely). Rarely appearing before the third day, it as rarely occurs after the twelfth, generally manifesting itself within the first week.
Its cause has been thought to be navel-string injuries; inflammation of the umbilical arteries or vein; reflected irritation from the skin, the bowels, or the external genitals; uræmic encephalopathy; cold and dampness; defective ventilation; and indirect pressure upon the cerebellum and the medulla.
The supposed causative umbilical lesions have time and again been found in young infants presenting none of the symptoms of the disease; and the same is true of the vessel inflammations24 and of the reflex irritations. Atmospheric and climatic states and the hygienic condition of the child and its surroundings, however much they may contribute to the development of the affection, cannot be regarded as directly producing it; though experience has shown (as in the lying-in hospitals before referred to) that by securing proper care of the children, by improving the ventilation, and by preventing overcrowding, its prevalence may be very greatly diminished.
24 Mildner of Prague reports that in 46 fatal cases of inflammation of the umbilical vein, convulsions occurred in but 5, and in these the spasms were not like those of tetanus.
Forty years ago Marion Sims believed that he had discovered the exciting cause in “pressure exerted on the medulla oblongata and its nerves, the result most generally of an inward displacement of the occipital bone,” occasionally, though rarely, of the parietal. That intracranial pressure may give rise to tetanic symptoms is beyond question, seizures identical with those of tetanus having been observed in connection with tumors of the cerebellum (Hughlings Jackson), as also trismus, confined even to one side (Wernicke).
In some cases without doubt the occipital depression is secondary, the result of intracranial shrinkage; and even if primary, there may be no lockjaw.25
25 H. G. Lyttle of New York recently reported the case of a child two months old whose occipital bone was depressed and overlapped by the parietals, in which there had been no trismus, though the child had slight convulsive movements of the hands and rolling of the eyes.
Parrot regarded the disease as a form of eclampsia, the uræmic encephalopathy manifesting itself as one or other of the three varieties recognized (by Cederschjöld) a half century ago—viz. trismus, tetanus, and ordinary eclampsia. The articular rigidity, especially noticeable in the temporo-maxillary joint, he held to be largely independent of the convulsive tonicity of the muscles, and due in no small measure to induration of the overlying soft parts, such hardening being the result of that loss of fluid which, as it affects the body in general, produces the rapid and extreme emaciation which is so characteristic of the disease.26