Among the anatomical findings in cerebral infantile palsy- a place must be reserved for microcephalus. As has already been explained, the subdivision of this condition into pseudomicrocephalus (terminal stages of a cerebral disease) and genuine microcephalus (failure to de velop beyond a certain stage) is practically impossible. Combinations with abnormal types of cerebral convolutions, particularly the persistence of differentiating fissures (macrogy-ria), is not infrequent in microcepha lus. One also finds cysts, foci of softening—often with haamorrhagic contents—and connective tissue scars in cerebral infantile palsy-, which are to be regarded as localized cerebral processes.
These lesions arc all found in the brain cortex, in the white matter of the cerebral hemispheres, and in the region of the basal ganglia.
It would be quite justifiable to include congenital or acquired hydrocephalus as well as microcephalus among the causes of cerebral infantile palsy. As a matter of fact, however, this is not done and it is customary to describe cases of hydrocephalus as a separate clinical group, although they have no better claim to nosologic independence than the cases of cerebral infantile palsy.
Symptomatology.—" The etiology, symptomatology and pathology of cerebral infantile palsy arc like three large chains of mountains, and the peaks of one group are connected with the summits of another only by the most difficult passes." Such is the simile with which Peritz graphically describes the difficulties that are encountered when one attempts to bring the symptoms of this disease into harmony with certain definite anatomical changes. We shall therefore practically restrict the present exposition to a mere clinical enumeration of the signs of cerebral infantile palsy, and make only the most cautious attempts to establish a connection between the symptoms, and the localization and nature of the changes existing in the brain.
We distinguish infantile hemiplegia and infantile diplegia, according as the extremities of one or both sides are involved. IIemiplegia is characterized by paresis of one facial nerve and spastic weakness of the arrn and leg on one side of the body. The right side is somewhat more frequently attacked than the left. The facial palsy is limited to the middle and inferior branches; it varies greatly in degree and, in older cases particularly, is often barely perceptible. The paralysis is best seen when the child beigns to laugh or cry or speak, and is less distinct during rest and when the facial muscles are in active play. In protracted cases of facial palsy, spasm of the paralyzed muscles is sometimes pro duced, so that the sound side appears more smooth and the picture of a crossed paralysis of the face and extremities is simulated. The arm
lesion quite often manifests itself in permanent contractures; the elbow; and wrist-joints are flexed and the arm is held close to the body; fixation in extension is more rare. When the paralysis and contractures are of this pronounced type, active movements are practically impossi ble, and pass:lye movements encounter a violent resistance. In other cases there is only a marked rigidity of the muscles; movements are possible, but they are awkward and ineffective. The paralysis is always most marked in the hand (in contradistinction to spinal palsy). The fingers are folded over the thumbs and it requires considerable effort to open the hand; the finer movernents of the hand are performed only with great difficulty. Even when the signs of impaired function are less marked in the arm, the movements of the hand are still distinctly limited. The legs also present a typical spastic hemiplegia, with exten sion at the hip- and knee-joint and plantar flexion at the ankle-joint. Pes equinus with spasticity is quite often produced. Even when the paralysis is comparatively mild, the disturbance of the gait is quite marked; the child drags the leg and swings it around (circumduction) in bringing the foot forward. When the gait is not especially interfered with paresis of one leg may reveal itself in the child's inability to stand alone on the affected leg, to hop, or to rise on the toes. When the child sidesteps to the sound side, the paralyzed leg is dragged instead of being lifted clear, because the movement increases the spasm of the adductors (flankgait, Schuller). Partial monoplegia (monoparesis) of one arm or leg does not occur in cerebral infantile palsy, although the condition may- be simulated when the paralysis is much more pronounced in one extremity than in others.
Paresis and spasm are therefore the characteristic features of cere bral hemiplegia. They may, however, be combined very unequally. Thus, we see eases in which the rigidity of the extremities is pronounced, while the paralysis is quite moderate. Again, it may happen, for example, that the paresis and the increase in the muscle tone are quite marked in the leg, while the arm presents only a slight increase of the reflexes. In short, the involvement of the extremities in cerebral infantile palsy is by no means uniform, and one may see in the same individual in the course of time a diminution of the palsy and, not infrequently, an increase in the contractures.