RACHIOTOMY 



1232 



RADIATION 



instrument devised by Aral for opening the vertebral 

 canal without injury to the cord. 



Rachiotomy [ra-ke-of -o-tne) [pdx'S, spine; te/uveiv, to 

 cut]. Incision into the vertebral column. The oper- 

 ation of cutting through the spine of the fetus to facili- 

 tate delivery. 



Rachiophyma (ra-ke-o-fi' '-mah) [paxLQ, spine ; <j>vfia, 

 growth]. A spinal tumor. 



Rachipagus (ra-kip'-ag-us) [pax^C, spine ; nayoq, that 

 which is fixed]. A. double monster with the indi- 

 viduals joined at the spine. 



Rachis (ra'-kis) [paxig, spine: //. , Rachides\ The 

 vertebral column. In biology, the main petiole of a 

 compound leaf ; the axis of inflorescence ; the shaft of 

 a feather. R. nasi, the line extending from the root 

 to the tip of the nose. 



Rachisagra (ra-his-a'-grah). See Rachiagra. 



Rachischisis (ra-kis'-kis-is). See Spina bifida. 



Rachitae (ra-kit'-e) [p&xiQ, spine]. The muscles at- 

 tached to the spinal column. 



Rachitic (ra-kit'-ik) [p&xig, spine ; trig, inflammation]. 

 Affected with, relating to, or of the nature of rachitis ; 

 rickety. R. Rosary, R. Rose-garland, the row 

 of nodules appearing on the ribs, at their junction with 

 the cartilages, in rachitis. See Beads, Rachitic. 



Rachitis (ra-ki'-tis) [paxig, spine; trig, inflammation]. 

 I. Rickets, the " English disease" a constitutional 

 disease of infancy, characterized by impaired nutrition 

 and changes in the bones. Rachitis was first accu- 

 rately described by Glisson, in the seventeeth century, 

 The' disease comes on insidiously at about the period of 

 dentition, and three general symptoms are usually pres- 

 ent — a diffuse soreness of the body, slight fever, and 

 profuse sweating about the head and neck. Coincident 

 with these the skeletal lesions appear, the chief of which 

 are the bending of the ribs, the arching of the long 

 bones, with thickening at the junction of the shaft and 

 the epiphysis, and the development of hyperostoses on 

 the frontal and parietal eminences, producing the caput 

 quadratum. Dentition is delayed, nervous symptoms 

 are marked, as peevishness and sleeplessness, and in 

 some cases convulsions and laryngismus stridulus ; and 

 all the manifestations are accompanied by a state of 

 general weakness. The cartilage between the shaft 

 and the epiphysis of the longbones is greatly thickened, 

 the line of ossification is irregular and more spongy and 

 vascular than normal, and beneath the periosteum, 

 which strips off easily, there is spongioid tissue 

 resembling decalcified bone. Chemic analysis shows 

 a marked diminution in the lime-salts. Kassowitz re- 

 gards the hyperemia of the bone, the marrow, the car- 

 tilage, and the periosteum as the primary lesion, on 

 which all the others depend. 2. In biology, a disease 

 causing abortion of the fruit or seed. R. adultorum, 

 osteomalacia ; mollities ossium. R. annularis, con- 

 genital rachitis characterized by the production, after 

 birth, of furrows of the bones and fractures (Winckler). 

 R. micromelica, intrauterine rachitis, characterized 

 by shortening of the limbs and thickening of the di- 

 aphyses (Winckler). R. senilis. See R. adultorum. 



Rachitome (ra'-kit-om) [pax^g, spine ; rifiveiv, to 

 cut]. An instrument for opening the spinal canal. 

 See Rachiotome. 



Rachitomous (ra-kit'-o-mus) [paxtg, the spine ; roiiog, 

 cut]. In biology, applied to the vertebrae consisting 

 of separate pieces, or to animals possessing segmented 

 vertebrae. Cf. embolomerous. 



Rachitomy (ra-kif ' -o-me) [pdx'g, spine; m/iveiv, to 

 cut]. I. Section of the spine. 2. Decollation of the 

 fetus. 



Rachoma, Rachosis (ra-ko'-mah, ra-ko'-sis) [p&xig, 

 spine]. I. Relaxation of the integument of the 



scrotum. 2. The production of a ragged, irregular 

 abrasion. 



Rachylysis (ra-kil'-is-is) [p&xig, spine ; /.vaig, a solu- 

 tion]. A method of forcible correction of lateral 

 spinal curvature ; the abnormal curve is opposed In- 

 fraction or pressure applied by means of apparatus. 



Racial (ra'-se-al) [origin obscure]. Pertaining or due 

 to one's race. 



Rack (rah). See Arrack. 



Raclage (rak-lahzh') [Fr.]. The destruction of a soft 

 growth by rubbing, as with a brush or harsh sponge ; 

 grattage. 



Raclement. See Raclage. 



Racleur (rah-klur'). See Curet. 



Radcliffe's Elixir. See Tinctura aloes composita. 



Rademacher's Plaster. See Plaster. 



Radesyge (rad-e-si'-ge) [Norwegian]. A disease pop- 

 ularly known as Scandinavian syphilis, or Norwegian 

 leprosy, bearing more or less similarity to the yaws. 

 and characterized by malignant ulceration and other 

 cutaneous, lesions. It occurred in the last century in 

 an endemic form in Norway, the east Adriatic coast, 

 Scotland, and Canada, and is regarded by some autho- 

 rities as a syphilitic, and by others as a leprous disorder. 

 R. istrica. See Scherlievo. R. scabieuse. 

 Spedalskhed. R. scotica. See Sibbens. 



Radiad (ra' -de-ad) [radius, a spoke]. Toward the 

 radial aspect. 



Radial (ra'-de-al) [radius, a spoke]. Pertaining to 

 the radius or bone of the forearm. In biology, diverg- 

 ing from a common center. Relating to the radiating 

 processes of animals, or to the ray of an umbel, or the 

 ligulate corolla of an outer floret of Composite. 

 Gcebel uses it in opposition to bifacial or dorsoventral. 

 R. Artery. See Artery. R. Aspect, the aspect or 

 view from the side on which the radius is situated. R. 

 Bundle, in biology, a fibro-vascular bundle in which 

 the xylem is arranged in rays, with the phloem in in- 

 tervening rays or masses. R. Fibers (of the Retina), 

 Miiller's fibers. R. Fossa, a depression on the 

 humerus for the reception of the head of the radius 

 in flexion. R. Glands, lymphatic glands of the 

 forearm following the radial vessels. R. Nerve. 

 See Nerve. R. Tap, percussion of the lower end 

 of the radius to elicit the reflex contraction of the 

 biceps and supinator longus. R. Veins. See Veins. 



Radiale [ra-de-a' -le) [radius, ray: //. , Radia/i<7~\. In 

 biology : (a) the radio-carpal or scaphoid bone of the 

 wrist ; cf. ulnare ; (b) one of the cartilages at the 

 base of the fin in certain fishes (Elasmobranchs\ 

 one of the rays of a crinoid cup. 



Radialis (ra-de-a' '-lis) [L.]. Pertaining to the radius. 

 Various muscles are so called. See Muscles, T<: 



Radiate (ra'-de-dt) [radius, a spoke]. Diverging from 

 a central point; extending around the circumference 

 in rays; furnished with ray-flowers. R. -veined, pal 

 mately veined. R. Venation, or Veined, that form 

 of venation in which the main veins radiate from the 

 top of the petiole. 



Radiatiform (ra - de - a'- tif- orni) [radiatus, radiate ; 

 forma, form]. In biology, having a radiate a 

 ance ; applied to heads with the marginal disc-flowen 

 enlarged, but not ligulate. 



Radiatio (ra-de-a' -she-o) [I..]. See Radiation. 



Radiation (ra-de-a' -shun)[radiare, to radiate]. 1 >ivM 

 gence from a center ; having the appearance of rays. 

 R., Optic, of Gratiolet, a large strand of fibers con- 

 tinuous with those of the corona radiata, d 

 mainly from the pulvinar, the external and internal gen 

 iculate bodies, and the optic tract, and radiating into 

 the occipital lobes. R., Thalamic, certain tracts I 

 fibers from the optic thalami, which radiate into the 



