ABXOUMAL POSTERIOR PRESEXTATIOXS. 4G1 



effecting a passage through the Hinited space. When to tliis bulk is 

 ailded tlu' Hexed portion of the hnibs, it will be seen that this cause of 

 dystokia, generally most formidable in all cases, must be more so with 

 primiparip, and especially if some time has been allowed to elapse since 

 the commencement of parturition, if the " waters " have esca])ed, and 

 if amateurs and empirics have been interfering. With I'egard to this 

 interference, however, it must be admitted that it is less to be dreaded 

 in this presentation than perhaps in any other ; incompetent people are, 

 fortunately, at a loss how to act, as there is nothing to lay hold of, and 

 the nature of the malposition or the manner of remedying it is obscure, 

 perhaps unknown to them. 



In the diverse complicated positions of the posterior limbs in this 

 presentation, it may be remarked that they are more frequent and 

 difficult in the Mare than in the Cow — the increased difficulty being 

 doubtless due to the gi'eater length of the limbs in the Foal than the 

 Calf. 



The malposition of the hind-limbs may be of three kinds : 1. Limbs 

 incompletely extended in the genital canal ; 2. Flexed hocks, the 

 doubled limbs engaged more or less deeply in the passage ; 3. Ilind- 

 limbs completely retained in the uterus, and applied more or less closely 

 against the abdomen of the fujtus, the back part of the thighs and the 

 croup presenting at the inlet. 



We have mentioned that one or both limbs may be in a vicious posi- 

 tion ; even when the two are misdirected they may not be in the same 

 deviation — one leg being perhaps Hexed at the hock and the other ex- 

 tended forward towards the chest, one Hexed at the fetlock while the 

 other is bent at the hock, etc. 



This presentation is somewhat rare, and though differing little from 

 the natural one, yet frequently leads to death of the Foal, as birth 

 cannot take place without assistance ; though the Calf, having more 

 vital tenacity, can live longer, and therefore has more chance of being 

 born alive, even if help be not afforded for some time. It is generally 

 due to the prominent stiHes being arrested at the inlet by the thin 

 margin of the pubis in the Mare, or the inclined plane this part forms 

 in the Cow. When the hind-limbs become fixed the body of the fa'tus 

 continues to pass outwards, so that the fenuu-s become more vertical, 

 and this causes the croup to be raised against the lumbar region, and 

 finally to be jammed there. The accident is much less frequent in the 

 Cow than the Mare, probably because of the sloping border of the 

 pubis. 



Exploration discovers the soles of the hind-feet uppermost, with the 

 shank incompletely extended on the tibia, which again is partially 

 Hexed on the femur ; the stiHes are also found pressing against the 

 margin of the pubis, while beyond this the croup is jammed upon the 

 sublumbar arch. 



Indications. — These are : push the croup forward in the uterus during 

 the inten-als between the pains, while traction is made on the cords 

 which have been attached to the lower part of the legs. 



If the hind-legs chance to be incompletely extended in the reverse or 

 lumbo-ilial position — which is possible, particularly in the Cow — the 

 foetus should be pushed forwards, its hind-legs extended, and the 

 creature placed in the lumbo-sacral position, when delivery can be 

 completed. 



