ATAXIA

(Lat.),n.f. A*t(aët)-a?x(a>x\i2-a3. Gr., érafia. Fr., atarie. Ger., Ataxie. It., ata ia. Sp., ataxia, 1. Anciently, any morbid state, especially if characterized by disordered, irceular action, such as irregularity of the pulse, or by not conforming to the typical course. [Hippo crates, Galen (A, 314, 325).] 2 An a emblage of nervous symptoms characterized by irregular it and by want of correspondence to the gravity of the disease with which they are ap ently a ociated; indicative of a prim at r secondary cerebral affection of greater or le gravitly. ‘Pinel (A, 314).] 3. Inco-ordination of muscular action, especially of the kind mentioned under locomotor a. (q. v.). [D.] 4. A genus of gramineous plants of the tribe Phalarideæ, made by R. Brown, dist in i shed by the flowers being borne in thyrsoid panicles, each spikefet hearing 2 unequal glumes and 3 flowers, the lower one male and provided with 2 pales, the middle one neuter with 1 pale, and the upper one hermaphrodite with 3 anthers. Bentham and Hooker refer the genus to Hierochloe. [B, 19, 42, 121.]—Abortive locomotor a. Fr., ataxie locomotrice fruste. Syn.: tabes dolorosa, pan he tabes. The neuralgic form of locomotor a., in which the lancinating pains are the most prominent feature and may remain such for many years. [D, 35.]—Acute a. Locomotor a. of rapid development. [D, eon olic a. A form of muscular incoordination observed in drunkards, resembling locomotor a.; said to depend on peripheral neuritis. [D, 35; Dreschfeld (M).]—A. Hors field i i. A species of a. (4th def.) growing in Java, which, when crushed, emits a pleasant odor due to the presence of coumarin. {B, 19.]—A. mensium, A. menstru » See Menstrual a.—A. motus. See Locomotor a.—. spirituum. Fr., ataxie des esprits animaux. It., ata ia degli spirit i animal i. An instability of the nervous system to which Sydenham attributed nervous disorders, [A, 314.|—Bulbar a. Ger., bulbäre Ataxie. Locomotor a. occasioned by a lesion of the pons Varolii or of the medulla oblong at a. [A. Pick (D, 18).]—Central a. Ger., centrale Ataxie. A. due to disturbance in the centres which preside over co-ordination, [A. Pick (D, 18).] Cf. Sensor —Cerebellar a. Fr., ataxie cérébelle use. Ger., cerebelldre Ala: A, depending on disease of the cerebellum; usually to be Us geien by the patient's staggering from side to side like a drunken man and often falling to one ‘side. [A. Pick (M, 1).]|—Cerebral a. ù cerebrale Ataxie. A. due to a lesion of the cerebrum. _ [Friedreich, “Arch. f, path. Anat, u. Physiol. u. f. klin, Med.,” Ixviii, p. 216 (L).] —Choreic a. Fr., ataxie choréiforme. The muscular incoordination that accompanies the voluntary movements of patients with chorea, [D, 35.|—Diphtheritic a. A form which sometimes follows diphtheria and precedes the occurrence of diphtheritic paralysis. The main phenomena of locomotor a. are observed, and the attack may pa off without paralysis, or it may end in death from nervous exhaustion. [D, 40; A. Pick (M, 1).J— Drunkards’ a. See Alcoholic a.—Family a., Friedreich’s a., Hereditary a [Friedreich]. Fr., ataxié héréditaire. Ger., heredittre Ataxie. It., ata ia ered it aria. Friedreich’s disease; a rare and peculiar disease somewhat resembling locomotor a., but almost. always occurring in several children of a family, especially the irls, between the ages of twelve and eighteen years. The preiminary pains are usually absent; there is marked ataxia of the ‘ower limbs, which soon extends to the arms, and subsequently there is a disturbance of speech supposed to depend on incoordination, together with nystagmus. The disease lasts for many years, and, being incurable, ends in paralysis, contractures, and atrophy of the muscles involved. [A, 446.|—Hysterical a. An a emblage of hysterical phenomena’ resembling those of locomotor a., but usually without the darting pains. [D, 47.]—Locomotor a. Lat., a. motus. Fr., ataxie locomotrice.’ Ger., Bewegungsataxie. It., ata ia locomotrice. Sp., a. locomotriz.” Syn.: ‘progre ive locomotor (or motorial) a. [Duchenne] (or asynergy), pesearsor: spinal sclerosis, inflammation (or sclerosis) of the poser i or root-zones of the spinal cord (Hammond], tabes dorsal is (seu dorsualis) (Rembere} consumption of the spinal cord, gra degeneration of the posterior columns of the spinal cord een cerebral pacceleaial [Gull], Duchenne’s paralysis (or disease). A disease of the nervous system (commonly the terior root-zones of the dor so-lumbar portion of the spinal cord) usually occurring in middle-aged men, which is generally very chronic in its course, but is believed to prove fatal in all cases. The initial symptoms are variable, the most remarkable of them being lightning-like pains beginning in the back and following the course of the nerves of the lower limbs. After a short time, muscular inco-ordination of the lower limbs (or of the upper limbs also when the spinal lesions are situated at a high level) sets in and becomes the prominent symptom to which the affection owes its name. There is no lo of power in the muscles, and the patient’s lack of control over them is due to diminished sensibility, so that he is deprived of the normal guiding sensations, and has to depend almost entirely on the sense of sight—if he shuts his eyes, he is “often entirely unaware of the situation and position of his limbs.”* and is very apt to fall if he attempts to walk, The tendon reflexes, per tical any, that. of the patella, are almost always diminished or abolished. Visua) and auditory disturbances are frequent, especially contraction, ioequality, or reflex immobility of the pupils, paralysis of the ocular muscles, atrophy of the optic or the acoustic nerve, and auditory vertigo. ‘ Crises” are often observed, consisting of functional disturbances of the digestive organs or the laryngeal muscles. attacks of renal colic, and, in women, peroxyemsl of sexual excitement. Various diseases of the joints (tabetic arthropathies) are not uncommon, [A, 394, 446; D, 1.]—Menstrual a. Lat., a. mensium. Fr., ataxie menstruelle. An old term for vicarious menstruation, sometimes applied to other disorders of the menstrual function. [V. Poulet, “ Gaz. hebdom. de méd. et de chir.,” May 14, 1886 (M).] —Motor a. Ger., moforische A. 1. Locomotor a. 2, A disturbance of the nerve tracts which bear the co-ordinating impulses to the periphery. [D, 18.]—Muscular a. Fr., ataxié musculuire. Muscular inco-ordination from any cause. [Potain (L, 87).)—Paralytic a. of the heart. A condition observed in bulbar affections, without organic disease of the heart; characterized by palpitation, dyspnoea, weakne of the cardiac sounds, oedema, and dropsy. {"Gaz. hebdom. de méd. et de chir.,” Sept. 10, 1886, p. 605 (M).]— Progre ive locomotor a. Fr., ataxie locomotrice progre ive [Duchenne Ger., progre ive locomotor is che Ataxie. It., ata ia locomotrice progre iva. Sp., a.locomotriz progresiva. See Locomotor a.—Sensory a. Ger., sensor is che Ataxie. A form of a. (the existence of which is denied by Erb and Friedreich) attributed to disturbance of the nerve tracts leading from the periphery to the centres of co-ordination. [p, 18.) Cf. Motor a.—Spinal a. Fr., ataxie spinale. Ger., spinale Ataxie. See Locomotor a.— Static a. A term for the unsteadine of locomotor a. observed when the patient attempts to stand erect with the eyes closed and the feet side uy side; also for the uncertain movements of the upper limbs in the later stages of the disease. [D, 35.]