of Edinburgh, Session 1871 - 72 . 
659 
sciatic ligaments, may be accompanied by some degree of enlarge- 
ment of the outlet by the posterior nutation of the apex of the 
sacrum. 
To Schultze’s theory of the facilitation of the latter part of the 
second stage of labour by extension of the spine several objections 
may be made. First, it is inconsistent with his views as to the 
facilitation of the entry of the foetal head into the brim of the 
pelvis by flexion of the spine. That view is based upon the assump- 
tion that the child’s head enters the brim of the pelvis so as pretty 
nearly to occupy it and have a nearly vertical axis in the axis of 
the brim. If this be true of the foetal head at the brim, it will be 
true of it during its course, mutatis mutandis , and it will be true 
of that part of the body which occupies the brim when the child's 
head is pressing on the perineum. It will be impossible, therefore, 
by any change of the axis of the uterus to bring the line of the 
labour force to bear upon the perineum in the direction of a straight 
line as Schultze represents it. Second, the upper cylindrical solid 
portion of the ligamentous pelvis, having a length of at least an 
inch and a half, has a well-determined axis with which must corre- 
spond the axis of any body fully occupying it, if the body is of 
uniform consistence, — conditions with which the foetus nearly com- 
plies. If this be the case, the direction of the force of labour will 
follow the same axis, and no change of its direction above the brim 
of the pelvis, however produced, can have any effect upon its direc- 
tion in any part below the brim of the pelvis. Third, Schultze 
forgets that his practice is intended to produce or increase posterior 
obliquity of the axis of the uterus to the brim, to increase the 
supposed curve of the natural promontory, and that every addi- 
tional degree of that curve necessarily produces additional loss of 
power. The more, then, he extends the spine he will diminish the 
power of labour available at the outlet of the pelvis, instead of 
increasing it, as he expects. Fourth, if Schultze’s* views, as illus- 
trated by his diagrams, are correct, a dangerous amount and direc- 
tion of force would be brought to bear upon the perineum, a 
structure whose integrity is already sufficiently imperilled by a 
force whose direction is gradually changed as the foetus passes 
through the lower half of the ligamentous pelvis. 
* Lehrbuch der Hebammenkunst, fig. liii. 
