Recto- Vaginal Fistula 229 



tends to become more intensely infected than usual, and 

 this infection may extend through the cervical canal into 

 the uterine cavity and beyond. 



Consequently it is of importance that such lacerations be 

 repaired as promptly as possible. Owing to the constant 

 tension of the muscles and fascia extending from the vulva 

 to the ischial tuberosity, the margin of the sacro-sciatic liga- 

 ment, and the sacrum, it is difficult to retain the parts in 

 apposition while healing. Therefore it may be advisable to 

 isolate largely, upon one or both sides, the anus and vulva 

 from the adjacent structures by making two approximately 

 parallel incisions from above to below on either side of the 

 anus and vulva, extending through the skin and subcuta- 

 neous tissues, so that outward tension upon these can no 

 longer exist. After the injury has been repaired, the in- 

 cision will heal and the function of the parts be restored. 



B. Recto- Vaginal Fistula 



Recto-vaginal fistula, like the first type of ruptured peri- 

 neum, belongs virtually exclusively to the mare. Its origin 

 is the same. An extremity of the fetus, almost always a 

 hoof, pushes up through the roof of the vagina and rectal 

 floor into the rectum. The position of the deviated member 

 then becomes corrected, and birth is completed without the 

 tissues posterior to the puncture becoming divided. As a 

 rule, the erroneous position of the foot is probably corrected 

 by an attendant who, realizing the peril, quickly pushes the 

 foot from the anus and rectum back down into the vagina. 

 The opening persists. The result is analogous to the com- 

 plete rupture of the perineum. Feces drop through the fis- 

 tula and cause fecal infection. 



The prognosis and handling are the same as for complete 

 rupture of the perineum. 



C. Lacerations of the Cervix 



Lacerations of the cervix have been generally ignored. 

 Not alone have the parturient lacerations of the organ been 



