LOCOMOTOR ATAXIA (Neo-Lat., from Lat. locus, place + motor, mover, and Gk. ciratia, disorder, from a-, not + raEla, order, from rficrcrecv, tassein, to arrange), or TARES Don SALIS. A disease of the nervous system, com monly of the posterior root-zones of the spinal cord, characterized by incoordination of move ments and by sensory and trophic disturbances. It is not paralysis, but loss of power to order har moniously the muscles that move the body and maintain equilibrium. It begins insidiously and grows slowly. The earlier symptoms are usually disorder of vision, a girdle sensation, with shooting pains through the limbs: increasing or perverted sensibility, and disturbance in the functions of the bladder and of the rectum re sembling neuralgia or sciatica. Later. the pa tient feels that his walking is not firm and sure; that there is some soft substance between his feet and the ground: he walks with difficulty. and with short, hurried steps; each leg is lifted well up, but as he moves it forward, it is thrown out from him and the heel descends with force while the sole comes awkwardly after it He now re quires the aid of vision to walk at all, and looks steadily at his feet or at a point a little in front of them, and he cannot make a sudden turn with out great risk of falling. If he stands erect with his feet together or nearly so. and closes his eyes, he begins to totter, and would fall if not sup ported. These phenomena are not primarily the result of weakness of motor power, hut of de fective muscular coordination. Diminished sen sibility in the feet and legs is usual in this dis ease. The upper limbs are sometimes affected, so that, though the hands retain all their natural muscular power, the sufferer cannot unfasten a button, or pick up a pin, or feed himself. As
the disease progresses, this muscular ineuiirdina don (ataxia) increases until the person affected is unable to walk at all. Paralysis of various muscles may occur, notably of some of those of the eye. The involvement of the bladder pro duces a loss of the power of urination, and gen eral weakness results in death. Although usual ly going to a fatal termination, the disease is sometimes arrested, and appears to be quite conquered particularly in its'earlier stages. In most eases it extends over several years. Loco motor ataxia arises from disease of a portion of the posterior spinal ganglia, later involving the posterior columns and the posterior ner•e-roots, which become atrophied and degenerated. The exciting causes are not well understood, but ex posure to cold, overexertion, privation, intem perance, and mental anxiety have been suggested as probable. It is probable that syphilis is the most important single cause, at least 60 to 70 per cent. being due to this alone, or to syphilis combined with alcoholism. Anti-syphilitic treat ment results in amelioration in some eases. It is sometimes hereditary, and is more common among males than females. It is developed usually not till middle life, from the age of thirty to fifty. Beyond alleviation of pain, little can be done by medicine, though many remedies have been tried. Electricity has been recommended by eminent authorities. Perhaps the best course is to attend carefully to the general health and regimen. .Muell can be done for the ataxia by systematic exercises carried out under a physician's in structions. Consult Potts, Yerrous and Mental Disease (Philadelphia and New York, 1900).