TRICHORRHEXIS NODOSA. NODULAIv SWELI^ING- 

 AND SPLITTING OF HAIR. 



Debility, ringworm, nodular hair. Hair bursts with brush like end. 

 Cases in horse like singed hair. Causes : infection probable, disturbed in- 

 nervation, dry air, impairel nutrition. Treatment : shave, oil, vaseline, 

 petroleum, cantharides, sulphur, tar, favor .shedding coat. 



In a variety of conditions the hairs split up and break, leading 

 to bristling or baldness. In debilitated conditions, when the hair 

 is badly nourished, in ringworm when it is invaded by a crypto- 

 gam, and in the various nodular or ringed conditions of the hair 

 this brittleness and splitting appears. The term Trichorrhexis 

 (rexis a bursting forth) has been applied to one of these affec- 

 tions, in which the hair swells and bursts into a number of fila- 

 ments giving it a broom-like termination. Trofimo describes this 

 as affecting two-thirds of the horses of an artillery brigade, and 

 showing upon the back, croup, mane and tail in isolated patches. 

 Megnin, Trasbot and Roy have observed similar cases. The 

 affected hair a short distance from the skin swells into a grayish 

 white nodule and breaks across, leaving a tuft of fine filaments. 

 The patches look to the naked eye as if singed, but when the hair 

 is magnified the difference is easily made out, as there may be 

 several nodular enlargements on the same hair, and the brush- 

 like spread of filaments at the broken end is entirely unlike 

 the solid node on the end of a singed hair. 



The causes of the affection have not been demonstrated, though 

 indications point to an infection which gradually extends from 

 the first point of attack. This extension is not limited to 

 the area presided over by particular nerves, and there is no 

 other indication of disordered innervation. Trasbot has seen the 

 disease transmitted from horse to horse by the use in common of 

 combs, brushes and rubbers, and in other cases experimentally 

 by rubbing the scurf from a diseased animal on the skin of a 

 healthy one. From observations on the human subject Mont- 

 gomery looks on it as a result of extreme dryness and brittleness 

 of the hair, and charges dry climates and seasons, and an abuse 

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