DESTRUCTION OF THE PELVIC GIRDLE 185 



56. DESTRUCTION OF THE PELVIC aiBDLE IN THE 

 ANTERIOR PRESENTATION 



Fig. 71 



Object. In somewhat rare instances, perhaps most fre- 

 quently in the cow, the pelves of the mother and fetus be- 

 come interlocked, the antero-external angle of the fetal 

 ilium, I', becoming locked with the shaft of the maternal 

 ilium, I, at C in such a manner that any safe degree of trac- 

 tion fails to dislodge it. 



The interlocking is generally, if not always, caused by 

 traction wrongly applied. At the stage of expulsion or ex- 

 traction of the fetus, when the interlocking occurs, any 

 traction applied should be parallel to the long axes of the 

 posterior limbs of the cow : the head of the fetus should be 

 directed toward the hind feet of the cow. 



TecKnic. Remove one anterior limb subcutaneously, 

 (53) and eviscerate, (59) through an opening made by the re- 

 moval of two or three of the exposed ribs. Introduce the 

 chisel through this opening, carry it back with the 

 hand, place it against the shaft of the fetal ilium, I', and have 

 an as.sistant drive it through the bone from before to behind. 

 Revolve the chisel forcibly on its long axis to completely 

 break down the ilium and its periosteum. Then withdraw 

 the chisel, place it against the pubic brim either at the 

 symphysis pubis or opposite the obturator foramen, and 

 drive it through the pubis and ichium at either of these 

 points. The coxo-femoral articulation is thus detached 

 and isolated so that the entire limb may drop backward be- 

 yond its fellow, the remnant of the severed ilium, I', can 

 drop downward or move in any direction, the entire pelvis 

 thus loses its rigidity and undergoes great diminution in 

 size so that it can readily be withdrawn. 



