474 



FCETAL DYSTOKIA. 



branes. It therefore results, that even when the latter is in the lumbo- 

 sacral position, posterior presentation, and every thing is favorable, yet 

 delivery should hastened if it is desired to preserve the life of the young 

 creature. 



The other three posterior positions — lumbo-pubic and right and left 

 lumbo-ilial — are unnatural, and demand the intervention of the obstetrist. 



Besides, these positions, as well as the lumbo-sacral, may be compli- 

 cated by a vicious direction of the limbs, which may lead to as great, if 

 less varied difficulties, as those encountered in the anterior presentation. 



The varieties of dystokia met with in the posterior presentation depend : 

 I. On the difficulties depending on the lumbo-pubic and lumbo-ilial posi- 

 tions ; 2. Those due to a vicious direction of the hind limbs ; 3. Those 

 arising from the head and fore legs. Some writers have alluded to 

 dystokia from a wrong direction of the tail ; but this must be very rare 

 indeed. 



Fig. 132. 

 Lumbo-sacral Position. 



SECTION I. 



-DYSTOKIA RESULTING FROM THE LUMBO-PUBIC AND LUMBO- 

 ILIAL POSITIONS. 



LuMBo-PUBic Position. 



In this, the posterior reversed position, the foetus is lying on its back, 

 its croup and loins corresponding to the floor of the abdomen or the 

 pubis of the mother, with the fe^ and belly towards the sacrum. 



As a consequence of this reversed position, the hind-limbs, which 

 soonest enter the pelvis, are inclined upwards and backwards into the 

 genital canal, and they are therefore the parts that first meet the hand in 

 exploration. Saint-Cyr points out what might be a cause of error in this 

 exploration, in the following terms : " As the anterior face of the hoof or 

 claws is directed upwards and the plantar surface (sole) downwards, the 

 explorer might be inclined to think that it was an anterior vertebro- 



