Within a few weeks or months, or, it may be, simultaneously, a sense of unusual fatigue upon exertion, with muscular stiffness and increasing difficulty in ing or in using the arms, due to the de veloping spastic rigidity, is noted, and the patient seeks advice. On examina tion, in addition to the atrophy, which often more perceptible to touch than to vision, the limbs will be found more or less rigid and resistant to passive motion, giving the examiner a sensation as of bending a lead pipe. The knee-jerks and other deep reflexes will be found markedly exaggerated, and often early in the disease, and always in the well established disease, ankle-clonus and wrist-clonus are readily elicited. If the bulbar nuclei are involved, there may be wasting of the muscles of the face, with alteration in the expression and impair ment of function as regards speech, res piration, deglutition, and cardiac action. A symptom of importance is the altered electrical reaction to both the faradic and galvanic currents. The muscles respond more and more feebly to faradism the more advanced the disease. The quali tative changes with the galvanic current are present early, and it is not uncom mon to find decided alteration of the nor mal polar formula, with reaction of de generation within a few weeks or months. In the late stages of the disease the atrophic symptoms may dominate the picture, the rigidity disappears, the re flexes are lost, and the victim is reduced to a state of bedridden helplessness, but with unimpaired intelligence.
Diagnosis.—The diagnosis is a matter of no difficulty ordinarily. The picture is that of primary lateral sclerosis and progressive spinal muscular atrophy com bined. From other forms of myelitis and sclerosis presenting one or both of these symptoms, this disease is distin guished by the absence of sensory symp toms and of sphincter involvement. It is true that sensory symptoms have been occasionally noted in this disease, but such instances represent complicated and atypical examples, and have a different pathology.
Etiology.—It is not at all a common affection, is seen oftenest during middle adult life, and affects males chiefly. The etiology is not definitely understood, al though traumatism, exposure to extreme cold, and excessive physical exertion, if prolonged, are probable auxiliary factors etiologically.
Pathology.—The pathology, on the contrary, is unusually well defined and constant. In the spinal cord the lesions are found in the anterior horns and in the lateral and anterior pyramidal columns. In the anterior horns the lesions are prac tically identical with those observed in chronic poliomyelitis. The so-called giant cells are either atrophied or de stroyed altogether. In the motor tracts, both lateral and anterior, there is in all cases a well-marked sclerosis of these fibres, extending throughout their entire length, often into and beyond the pons and occasionally even to the subcortical motor fibres of the Rolandic area itself.
If the ponto-bulbar region is involved in the disease process, the motor nuclei are affected with degenerative atrophy ex actly as are the cells of the anterior cor nea. The peripheral nerves also undergo degeneration, which is of the parenchy matous type. In the muscles the essen tial fibres are replaced by connective tis sue and fat, the alteration in color and consistency being often readily apparent upon quite superficial infection.
In a microscopical examination of the brain and cord of a case of amyotrophic lateral sclerosis, many of the cells of the anterior cornua showed more or less pro nounced degenerative changes, but few of them were completely degenerated. The anterior spinal roots showed only moderate atrophy. Both pyramidal tracts were markedly degenerated, and there was an area of slight degeneration in the column of Goll. The motor nuclei in the medulla were apparently normal. Some amyloid bodies were found beneath the fourth ventricle, and in the spinal cord. Very peculiar bodies were found in the medulla about the vessels, which appear to have been colloid in nature. The giant-cells of the paracentral lobule were normal in appearance, but dimin ished in number. No traces of nerve degeneration were found in the paracen tral lobule, nor in the internal capsule stained by Marchi's method, nor in the pons in the cerebro-peduncles, nor in the capsule by Weigert's method. Degenera tion was found in one of the laryngeal muscles. The fact that bulbar symptoms existed without marked degeneration in the motor nuclei, is explained by sup posing that the central neurons above this level were degenerated, and gave rise to the symptoms. F. X. Dercum and W. G. Spiller (Jour. Nerv. and Mental Dis., Feb., '99).
Prognosis.—The prognosis is hopeless as regards cure so far as precedent is a guide. Early helplessness is the rule, and death occurs within a few years, though a fatal termination may be de layed by an induced or spontaneous re mission or arrest of progress, rendering the disease stationary for many months.
Treatment.—In the absence of any plan of treatment known to be effective as a means of cure, our efforts are limited by experience to purely palliative meas ures. Among these, rest, massage, elec tricity, and hydrotherapy are all of value. The victims of this disease should be con sidered legitimate subjects for therapeu tic experiment.
Primary Lateral Sclerosis.
Synonyms. — Spastic spinal paralysis; spastic paraplegia.