THE FEMALE PELVIS 



383 



Pelvis Major (False Pelvis) 



Maximum distance between iliac crests . . . lof inches 



Distance between antero-superior iliac spines . . 9! ,, 

 Distance between fifth lumbar spine and the front of 



the pubic symphysis (the external conjugate) . 7g ,, 



Pelvis Minor (True Pelvis) 



These measurements apply to the bony pelvis. The measure- 

 ments of the pelvis major, however, can be readily carried out 

 on the living subject, and the relation between the interspinous 

 and the intercristal diameters sometimes gives a good indica- 

 tion as to the condition of the pelvis minor. The external 

 conjugate can also be obtained, and, within wide limits, it helps 

 to determine the antero-posterior diameter of the upper aper- 

 ture (brim). When the measurement exceeds 8J inches in the 

 living subject, there is no shortening of the latter diameter 

 on the other hand, when the measurement falls below 6 \ inches, 

 the antero-posterior diameter of the upper aperture is definitely 

 diminished. 



When the external conjugate falls between these limits, 

 other measurements are required. Of these the most useful 

 is the diagonal conjugate. It represents the distance between 

 the inferior aspect of the pubic symphysis and the sacral pro- 

 montory, and it can be determined on vaginal examination. 

 Under normal conditions, the diagonal conjugate is rather 



