Symptoms.—In very young children the beginning of the disease, or at least the first symptoms, may not be recog nized, but may be interpreted simply as indications of slow development or un usual awkwardness. The child does not learn to walk readily; it stumbles and falls easily or staggers in attempting to stand or walk. The hands are used clumsily and co-ordination appears to be learned with unusual difficulty. In speaking, the child drawls its words. The develop ment of nystagmus, of curvature, or of talipes in some form may prove the first obvious and unmistakable evidence that more than a simple delay in development exists. The disease is much more readily recognized when the symptoms develop later in life, as at eight or ten years of age. Contrast with a previously normal standard renders the symptom-picture much more conspicuous.
The gradually or rapidly increasing ataxia of gait and station; the chorei form ataxia in using the hands; the slow, drawling, thickened or scanning speech; the nystagmus; the club-foot; the curva ture of the spine, and the paraplegia are pathognomonic when conjointly associ ated in early life in two or more members of the same family. Weakness in the legs is present early with the ataxia, and ultimately becomes a more or less com plete paraplegia. Sensory symptoms are rare, though, subjectively, headache and slight aching or pains in the limbs may be present. Vertigo is not uncommon. The sphincters are not involved until late in the disease. The knee-jerks are lost, as a rule. Atrophy of muscles and trophic lesions of the skin are exceed ingly uncommon except late in the ad vanced disease. The electrical reactions are usually undisturbed. In a very few cases paresis of the eye-muscles has been noted. Usually- some degree of impair ment mentally is present in the estab lished disease.
Diagnosis.—There are only two dis eases which are likely to confuse the diagnosis: disseminated sclerosis and Huntington's chorea. In the latter the disease occurs in middle life or later, as a rule; the mental faculties are more markedly involved; the choreiform movements are far more active and ex treme; the speech is jerky or explosive; and there is no curvature, no talipes, and usually no nystagmus. From multiple sclerosis the distinction is sometimes im possible. The family history as to direct heredity is of value, but the fact that a brother or sister is similarly affected is less valuable since Dreschfeld and others have reported multiple sclerosis in two members of the same family. The cra nial nerves are more frequently affected in disseminated sclerosis; the knee-jerks are often exaggerated; disturbances of sensation are much more common, which is true also of sphincteric involvement.
The tremor when present in Friedreich's ataxia is less of the intention type and more like that of chorea. Convulsions and crises, when present, point to mul tiple sclerosis rather than Friedreich's disease. Remissions do not occur in the latter, while they are not at all uncom mon in the former.
Etiology.—The essential predisposing factor is an inherent developmental de fect of the spinal cord, especially the postero-internal and lateral columns. The heredity is sometimes direct, but more frequently indirect. Organic in sanity, gross alcoholism, syphilis, con sanguinity of marriage, epilepsy, or some other degenerative neurosis may consti tute the ancestral or parental taint. A generation may be skipped, the parents being apparently healthy, but the grand parent a neurotic. Locomotor ataxia is rare in the family history of this disease. Direct inheritance of the disease itself was found by Griffiths in 33 out of 143 cases. It is somewhat more frequent in males than females (SG males, 57 fe males—Griffiths's table) and more than two-thirds of all cases develop symptom atically within the first decade of life (99 out of a total of 143—same author). The disease seems to be more common in America than elsewhere. judging from the published cases, and in this country the victims are, for the most part, from the rural districts rather than the cities. It is the rule to find more than one case in a family, and sometimes sev eral brothers and sisters may be affected in succession. The first obtrusive symp toms may follow an acute illness, espe cially the infectious fevers.
Pathology. — The gross pathological anatomy has been quite satisfactorily demonstrated in a number of reliable autopsies. The extent of the lesions may vary, however, considerably. The cord appears diminished in bulk and some times of eccentric contour macroscop ically. Occasionally two central canals have been found or the one central canal may be disproportionately large. Vari ous other developmental anomalies may be present. The morbid process is that of sclerosis, which is always well marked in the lateral pyramidal and postero internal columns, but may also involve the columns of Thick and the direct cerebellar tract. It does not invade the gray matter, which is usually separated from the diseased columns by a layer of healthy tissue. Dejerine believes the sclerosis found in family ataxia to be really a neurogliar sclerosis or form of so-called gliosis, due to a developmental ectodermal defect. The columns of Coll and the pyramidal tracts are affected in varying degree throughout their entire. course. The pathogenesis is as yet un determined.