IXrSRSIOX OF THE UTERI'S. r.77 



only incompletely so, then they remain cylindrical at their lower end, at 

 the centre of the cylinder being a depression or cuccal cavity. 



Inversion of the uterus is, of course, only possible when the os uteri 

 is dilated ; consequently, it occurs either immediately before or after 

 birth. 



Again, inversion is simple or complicated. It is simple when the 

 viscus is intact, uninjured, and not accompanied by the extrusion or 

 displacement of any other organ. ^Vhen it is wounded or torn, or when 

 there is accompanying hernia or protrusion of other viscera, then it is 

 complicated. 



As we have said. Ruminants are most liable to this accident : the 

 (/Ow coming first, then the Sheep and Goat ; the Mare is less fre- 

 quently affected, and the Sow and Bitch perhaps not so often as the 

 Mare. Inversion of the uterus has been observed in the Cat and 

 Rabbit. 



With the Bitch and Sow, incomplete inversion of the uterus is far 

 from uncommon, as is also simple invei'sion of the vagina, for which it 

 might be mistaken. In uniparous animals the whole of the organ is 

 usually inverted ; while in multiparous creatures, generally little more 

 than the portion which contained the foetuses is involved. 



Tlie accident has been observed in animals kept in houses and stables, 

 as well as in those roaming about at liberty ; and it has been known 

 from time immemorial. The Roman veterinarian, Yegetius, alludes to 

 it, and recommends the employment of an inflated pig's bladder as a 

 good pessary. 



Syviptoms. 



The symptoms of uterine inversion vary with its extent. With 

 uniparous animals, inversion always commences at the fundus of the 

 organ, most frequently towards the largest cornu where the greater 

 portion of the fa^tus was lodged. Under the influence of an irregular, 

 and kind of spasmodic contraction, this part is drawn or pushed in- 

 wards, just as the foot of a stocking is inverted ; and this action con- 

 tinuing, the fundus or cornu is more or less rapidly carried towards the 

 OS, through which it passes into the vagina {incomplete inversion), 

 dragging after it the body of the organ, which also becomes inverted as 

 it proceeds. 



It is rare indeed that inversion does not go beyond this ; for the con- 

 siderable alteration in position and relations which has already taken 

 place gives rise to sensations of discomfort and pain, and these re- 

 act on the nervous system, inducing contraction of the uterine and 

 abdominal muscles. Powerful and hurried expulsive efforts ensue, and 

 soon the organ is pushed beyond the vulva, where its own weigiit carries 

 it downwards, and renders the prolapsus complete — the lining or mucous 

 membrane having become external. 



W^hen inversion is complete, the uterus has the form of an enormous 

 pear or calabash-shaped tumour hanging between the posterior limbs 

 — the wider and rounded portion being inferior, and sometimes ex- 

 tending as low as the hocks, the narrow extremity or pedicle being at 

 the vulva, in the interior of which, and between the labia and the 

 tumour, is a more or less deep and circular cul-de-sac, according as the 

 prolapsus has involved a certain extent of the vagina. 



That the surface of the tumour is composed of the uterine mucous 

 membrane, is easily apparent from its softness and colour — which is 



37 



