OF THE PELVIS. 45 



115. As to the measurement of the oblique diameters, the length 

 of the neck of the femur has appeared to vary too much to permit 

 practitioners to repose much confidence in it ; but I think, on this 

 subject there has been a very general misapprehension ; for among 

 a pretty considerable number of well formed pelves I have never 

 found in this direction a difference exceeding a quarter of an inch, 

 more or less, than the one indicated. 



As the cristse of the ilia may be considerably raised or much de- 

 pressed, without the straits having undergone any modification, we 

 should be exposed to too many and too serious mistakes, were we 

 to take half the distance between them as the measure of the bis- 

 iliac diameter. This last is surrounded by too many muscles, and 

 moreover is of too little importance for us to measure it in any 

 other way than with the hand. 



116. The fingers suffice for ascertaining the state of the inferior 

 strait. According to the authors, the woman should be seated upon 

 the edge of a chair, but she may also be examined while standing 

 up. The ball of the fore finger is placed upon the point of the coc- 

 cyx, and the point of the thumb on the edge of the snb-pubic liga- 

 ment, after which the two fingers, being held at the same distance 

 apart, are referred to a graduated scale to ascertain the degree of 

 separation. While the extremity of the index is pressed against the 

 point of the coccyx, the radial edge of the finger, instead of the thumb, 

 may be pressed against the top of the pubic arch ; but there is more 

 danger in this method of painfully pressing against the external sexual 

 organs, if their sensibility happens to be excited. To measure the 

 ischiatic diameter, we must press the points of two fingers against the 

 lips of the ischia, at the spot where the great sacro-sciatic ligament is 

 inserted, taking care to push the fat aside by gentle pressure. 



117. Although it is true that this exterior exploration does not 

 enable us to pronounce with confidence as to the nature and degree 

 of deformity of the pelvis, it is nevertheless the only one we can have 

 recourse to in virgins ; in other women it is permissible to attempt 

 the internal mensuration, which it has been proposed to perform in 

 a great many different ways. 



118. Coutouly was the first to propose measuring the interior 

 of the pelvis by means of a pelvimeter, which bears his name. It 

 is impossible to convey a clearer idea of such an instrument, fre- 

 quently modified by its inventor, than by comparing it to the shoe- 

 maker's rule employed in measuring the length of the foot. It is 

 introduced, closed, into the vagina, after which it is opened, and one 

 of its branches rests against the pubis, while the other is applied to 

 the sacro-vertebral projection. Now, the movable or sliding branch 



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