Application of Traction 587 



ing, it is located below the pubic brim and must mount that 

 obstacle in order to gain the pelvic canal. Presenting thus, 

 if traction should be necessary or desired, it should be applied to 

 the fetus somewhat obliquely upward, so as to lift the fetus up- 

 ward and backward over the pubic brim. 



During the progress of the fetal head through the pelvis, the 

 traction should be directly backward or slightly upward and 

 backward, but, when the fetal head arrives at the vulva, if the 

 traction is continued upward it tends to force the poll of the head 

 too powerfully against the superior vulvar commissure, and not 

 only tends thereby to cause an obstruction to delivery by jam- 

 ming the fetal head against this part, but also endangers the in- 

 tegrity of the superior commissure of the vulva it.self and tends 

 to cause more or less laceration of it. Consequently the direc- 

 tion at this point should be somewhat downward in order to 

 avoid, as far as possible, any injury to the soft parts. 



After the head has passed through the vulva, the traction 

 should be continued more and more downward as the body of the 

 fetus advances, until finally, when the withers have passed the 

 vulva, the line of traction should be almost perpendicular to the 

 long axis of the spinal column of the mother or parallel to the 

 long axis of the posterior limbs of the mother. 



If the animal is standing, the direction of traction, when the 

 fetus is well advanced, should be immediately downward toward 

 the floor, or if she is lying down it should be directed toward 

 her hind feet. Such a direction in traction permits the ventral 

 wall of the fetal body to become .somewhat relaxed, and in this way 

 the fetal viscera may pass backward or forward in the body cav- 

 ity and thus escape from that part of the cavity which is being 

 most compressed in the birth pas.sage, thereby decreasing the 

 diameter of the fetal body at the most critical point. 



The downward direction of the traction pulls the tuberosities 

 of the fetal ilia downward from the uppermost part of the 

 maternal pelvis, and prevents their becoming interlocked with 

 those of the mother. 



Unless care is exercised at this time, the fetal and maternal 

 pelves become immov-ably locked. We have repeatedly seen this 

 occur where one or two honses have been hitched to the head of 

 a calf and violent traction employed in a direct line without 



