DYSTOKIA DEPENDING ON ANTERIOR PRESENTATION 441 



SECTION I. DYSTOKIA DUE TO THE FORE LIMBS. 



In the anterior presentation, and what we have designated the " normal 

 position," the two fore Hmbs of the foetus are extended in front towards 

 the pelvic inlet, the head being also extended and resting either upon or 

 between the legs, the distal extremity of which extends beyond its nose — 

 the whole forming a wedge-shaped mass. Consequently, the fore feet 

 should be the first parts to pass through the genital canal ; and if only 

 one appears with the head, or if the latter alone offers, then one or both 

 of the anterior limbs are in a wrong direction, and birth may be hindered 

 if they are not adjusted. The directions they may assume are generally 

 four : I. They may be incompletely extended in the pelvis ; 2. They may be 

 crossed over the neck ; 3. They may be bent at the knees ; 4. They may be 

 extended completely under thefcetus. Each of these misdirections may be 

 met with in the four principal positions of the anterior presentation, and, 

 as has been mentioned, one or both limbs may be involved ; if the latter, 

 then the direction may be the same or different. 



The cause of misdirection of the limbs is not well ascertained. In 

 many cases it may be due to insufficient dilatation of the os uteri, which 

 hinders their advancing with the head : the joints of the limbs readily 

 flexing when the feet come in contact with the cervix, while the uterine, 

 contractions propel the more rigid head and neck into the vagina. The 

 misdirection may also primarily occur during intra-uterine existence, and 

 before parturition sets in, and particularly if the fcetus dies before birth, 

 when its position is not the same as at that period. There can be no 

 doubt, however, that the accident generafly happens during parturition. 



I. Anterior Limbs incompletely Extended in the Pelvis. 



As might be inferred, this misdirection of the limbs differs but little 

 from that which they assume in normal parturition, they being only par- 

 tially retained, and the head more or less in advance of them. It is 

 usually due to the shoulders not being closely applied to the chest of the 

 foetus, and the elbows, consequently thrown wide apart, coming in con- 

 tact with the brim of the pelvis, thus proving an obstacle to the progress 

 of the young creature. It appears to occur generally in the vertebro- 

 sacral position, and most frequently in the Cow. It may also be owing 

 to the flexion of the fetlocks, when the feet meet with any trifling ob- 

 stacle. 



Indications. 



The indication in such a simple case as this is obvious — straighten the 

 fore limbs, and bring them to their proper height in the pelvis. Very 

 often this cannot be done by mere traction, which, in extending the arms 

 of the foetus, brings the elbows still further away from the body. In such 

 circumstances retropulsion must be resorted to, the body being pushed a 

 little beyond the pelvic inlet ; then traction being employed, the limbs 

 are readily extended to their natural position, and delivery may be ac- 

 complished with further assistance. 



2. Fore Limbs Crossed over the Neck. 



Saint-Cyr, asserts that this complication '-^ not very uncommon in the 

 Mare, less frequent in the Cow ; and he, with many other veterinary ob- 



