PELVIS PRESENTATIONS. 461 



of again suggesting to students and young accoucheurs, that if, in 

 turning by the feet, they wish to avoid the risk of often killing the 

 foetus, they ought never to lose sight of the fact that the head cannot 

 rotate on the spine more than a quarter of a circle, without luxating 

 it, or straining the spinal marrow, in a very dangerous way; that, in 

 general, it does not follow the motion of the trunk of the body, by 

 means of which attempts are made to rotate it; that it is impossible, 

 in any case, to affirm that it has rotated, merely on the ground that 

 the back, for example, has been turned from behind forwards; conse- 

 quently, that in any species of manoguvre whatever, we should com- 

 mit a very great error if we caused tiie child's body to turn more 

 than a quartor of a circle, without being assured that the head ac- 

 companies it in its movement. 



1041. Neither can I leave this subject without returning for a 

 moment to the consideration of the manoeuvre recommended by 

 Baudelocque for bringing the child's back in front, and which was 

 spoken of some pages back. It would, in my opinion, be wrong to 

 rely upon such attempts. If the womb is but slightly contracted, 

 it is useless to act in that way; when, on the contrary, the foetus is 

 forcibly compressed, the force which we exert upon it from below 

 upwards, seldom extends as far as the head, and even then it cer- 

 tainly does not change the general disposition of the womb, so as to 

 render the child at all more movable. This is not all; if it be not 

 certain that we shall be enabled, in this way, to render the rotation 

 of the occiput easier, it seems to me manifest that the abdomen, the 

 thorax, and even the cervical portion of the spine would not always 

 safely bear the various kinds of pressure and the twists to which 

 they will necessarily be subjected; lastly, to express my unreserved 

 opinion, I will say that this precept of Baudelocque seems to me to 

 be more the fruit of imagination than of observation, and that mo- 

 dern writers ought, previously to copying it, at least to have called it 

 in question and submitted it to a new examination. 



SECTION 4. 



Presentation of the Arm. 



1042. The premature escape of the arm does not, of itself, con- 

 stitute a position, and forms only a complication of other positions, 

 particularly that of the shoulder. Both arms have been seen, but 

 rarely, to present together at the vulva; unless brought there by 

 inconsiderate manoeuvres, they could not both thus descend except 

 in back or sternum positions. It is said that they have been both 



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