SPLINTS. 241 



Periosteotomy, which consists in cutting down on the splint and 

 thus dividing the periosteum (covering membrane of the bone), 

 gives, as a rule, great relief to the lameness caused by the painful 

 pressure of the bony enlargement (the splint) on the highly sensi- 

 tive periosteum, which is hard, inelastic, and plentifully supplied 

 with nerves. Also, by cutting deeply into the enlargement, the 

 inflammation is relieved by the bleeding from the congested blood- 

 vessels within the bone, as well as by division of the over-stretched 

 covering membrane. 



Periosteotomy is best performed on the horse when he has been 

 cast (p. 652) and properly secured. In order to diminish the 

 sensibility of the part, make four or five subcutaneous injections 

 (p. 644), near the intended incisions, of about 10 drops eaoh of a 5 

 per cent, solution of hydrochlorate of cocaine ; or put the animal 

 imder the influence of chloroform (p. 618). Having disinfected the 

 instruments (p. 70) and shaved off the hair of the part to be 

 operated on, apply an Esmarch bandage from the hoof to above the 

 knee, put on a tourniquet ; and cut deeply into the enlargement, 

 through the skin and periosteum. Before Lister demonstrated the 

 immense advantage to be obtained from treating surgical wounds 

 antiseptically, such an incision would have taken a long time to 

 heal, and have left a very ugly scar ; but under the new mode 

 of treatment, the separated edges quickly unit©,' and the resulting 

 blemish is trifling. 



Surgical removal of a splint can be performed by casting the 

 horse, injecting cocaine (p. 620) or giving chloroform (p. 618), 

 applying an Esmarch bandage and tourniquet, disinfecting the 

 part, and making a longitudinal incision through the skin in such 

 a manner as to expose the enlargement, which can be removed by 

 a gouge or bone forceps, while the cut edges are held back on 

 each side. The part is treated antiseptically (p. 70), sutured 

 (p. 73), dressed with tannoform or some other suitable 'antiseptic 

 (p. 67), covered with a few layers of antiseptic cotton-wool, and 

 bandaged. Colonel Nunn remarks that : " I always removed the 

 growth with a McEwan's osteotome, either gouge or chisel shaped, 

 and a mallet. I found that it was well to employ a broad one, so 

 that the whole of the growth should be removed and no trimming 

 up be required, and with this object I took care to dissect the 

 periosteum well away from the splint. I also was very careful 

 not to close the skin wound until all bleeding had absolutely 

 ceased after the tourniquet had been removed, and the few cases 

 that went wrong I attribute to neglect of this precaution, the sug- 

 gestion of which I am indebted to a friend in the Indian Medical 

 Service. In my later cases, in which this was observed, the woimd 

 healed by first intention without any trouble. 



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