436 FCETAL DYSTOKIA. 



difficulty in releasing them. In any case, the lower jaw and feet should 

 be corded ; this being done, the chest is pushed forward into the 

 uterus, when the upper parts of the limbs accompany it. The hand 

 can now fully extend the legs and bring them into the vagina along 

 with the head, and traction will complete the delivery. 



One or Both Fore-Limbs flexed at the Knees. 



The fore-limbs flexed at the knees, and fixed under the neck and chest, 

 are a very frequent and often troublesome comphcation. It is generally 

 foimd in the Mare and Cow ; when it occurs in the Sheep and Goat it is 

 rarely of any importance, as delivery can usually take place without 

 assistance ; in the young of Carnivora, the metacarpal bones are too 

 short to offer any obstacle when the knee is flexed. 



This misdirection of the fore-hmbs may occur in all the positions of 

 the anterior presentation, but chiefly in the dorso-sacral position. One 

 or both hmbs may be flexed, and the comphcation is not unusually 

 accompanied by a misdirection of the head ; hence, there are several 

 varieties of the complication, the most important being those due to the 

 general position of the foetus. It may occur in three positions — the 

 dorso-sacral, dorso-pubic, and dorso-ilial. 



Dorso-Sacral Position of the Foetus. — If at the moment when the 

 limbs of the foetus enter the pelvic inlet, they are not quite extended 

 and the feet are slightly below the level of the anterior border of the 

 pubis, the uterine contractions push them against this border, and there 

 they remain ; at the same time the head enters the inlet, and as it pro- 

 ceeds the limbs become flexed, the knees are bent and advance with it, 

 but the metacarpals and phalanges are directed backwards beneath the 

 forearms, and the hmbs thus doubled are applied against the neck. We 

 have therefore the head, fore-arms, and metacarpals in one mass, 

 entering or being propelled into the limited space afiorded by the inex- 

 tensible pelvic circle, and, according to circumstances, the hand of the 

 obstetrist will meet with these parts in varying relative positions, 

 depending on the stage of labour. When parturition has only recently 

 commenced, the head has entered, or is about to enter, the inlet, and 

 the limbs placed beneath it are still somewhat free in the uterine cavity, 

 while the foetus itself is not immovably fixed if the waters have not long 

 escaped. But when labour has been progressing for some time, the 

 head is well advanced in the passage — sometimes as far as the vulva ; 

 but considerably behind it are the limbs, imbedded on each side of the 

 jieck — the knees towards the head, the feet at the elbows. 



With the smaller Euminants, as already remarked, birth may 

 take place spontaneously even now, as they often have more than 

 one fcetus, and these comparatively small, compared with the pelvic 

 diameter; while the bones are elastic and yielding. But with such 

 animals as the Cow and Mare the foetus is nearly always single and 

 voluminous, and its skeleton is rigid and unaccommodating, and can 

 only undergo a very small reduction in size during its passage through 

 the pelvis. 



Therefore it is that, in the larger domesticated animals, such a devia- 

 tion of the limbs is always a serious cause of dystokia — not so much 

 from the increased volume that the doubled-up limbs gives to the neck, 

 as because the arms, incompletely extended on the shoulders, retain 



