From lack of competent observation during the initial stage it is really not quite certain whether any degree of paresis precedes the paralysis; but from the testimony at present accumulated the paralysis is nearly always complete when first observed. This is in striking contrast with adult spinal paralysis. In some few cases the paralysis has been observed to creep on slowly, and not reach its maximum for several days (Ross). Laborde relates a case where recovery from a first attack of paralysis was followed by two relapses in the same limbs at intervals, each ushered in by fever. After the second relapse the paralysis remained permanent.
Significance of Original Extent of Paralysis.—The question of the original distribution of the paralysis is of special interest in connection with that of the original distribution of the morbid process in the spinal cord. The real effect of the latter cannot be adequately measured by the permanent paralyses; for, as will be seen, it is not unusual to find traces of an extensively diffused process in the cord in cases of quite partial paralysis.
It is interesting to notice that certain muscles are always exempt from paralysis. With the exception of a single case of paralysis of one temporal muscle, cited by Seguin,22 the muscles of the head, eyeballs, ears, larynx, and pharynx are always exempt, as are also the diaphragm and intercostals. The arrest of the spinal lesion below the medulla explains the immunity of muscles supplied by the vagus and spinal accessory nerves. But since the cervical plexus is often involved, the constant escape of the diaphragm, innervated by the phrenic nerve which comes from this plexus, is remarkable. Still more so the immunity of the intercostal muscles, whose nerves arise in the dorsal region—a position of the cord frequently affected. This fact tends to confirm Ross's hypothesis, that the nuclei of the intercostal nerves lie in the vesicular columns of Clarke—columns confined to the dorsal region of the cord, and which are invariably found intact at autopsies of atrophic paralysis.
22 Loc. cit.
The immunity of these respiratory nerves explains the absence of the dyspnœa which is so marked in Landry's ascending paralysis. In the adult case described by Schultze and Erb23 dyspnœa was present for a short time. The disease terminated fatally twenty months from the time of invasion. In this case traces of myelitis were found extending through the dorsal region of the cord, and including not only the anterior nerves, but, to a less degree, the columns of Clarke.
23 Arch. Virch., Bd. lxviii.
The facial nerve (itself a respiratory nerve) shares the immunity of the phrenic and intercostals. In the cases in which facial paralysis has been noted the limb paralysis has been hemiplegic, as in Seeligmüller's twentieth case. A cerebral origin is then always to be at least suspected.
Barlow24 has seen 6 cases of paralysis of the facial, but the histories render a cerebral paralysis more probable in 4 out of those 6. Henoch25 gives a case of paralysis of left arm, accompanied by paralysis of corresponding facial nerve. The latter rapidly recovered, but the paralysis of the arm persisted and was followed by atrophy. Ross26 implies that the sides of the neck, face, and tongue are always at first implicated in spinal hemiplegic paralysis, but do not remain permanently affected.
24 Loc. cit.
25 Loc. cit., p. 205.