PELVIC LIMBS 679 



practically, parallel with the lower wall. The pelvis contains the 

 bladder and the last division of the bowel, called the rectum, and 

 in the female, between them, the vagina and part of the uterus. 



The outlet of the pelvis is between the body of the fifth caudal 

 vertebra, the tuberosities, and the posterior borders of the ascending 

 rami of the ischia. It is irregularly lozenge-shaped, pointed below 

 and narrow above. The transverse diameter, taken between the dorsal 

 tips of the tuberosities, is greater than the pubio-caudal diameter, 

 which extends from the posterior termination of the symphysis of the 

 pubes to the body of the fifth caudal. The plane of the outlet of the 

 pelvis faces downward and backward. 



The outer surface of the pelvis has been already described in the 

 consideration of the innominate bones, of the sacrum, and of the 

 caudal vertebrae. 



Nomenclature. The word pelvis is the Latin, from the Greek 

 pele, for a deep, wide vessel. 



VARIATIONS IN THE PELVIS. 

 VARIATIONS IN SIZE. 



The following are the more important measurements of the pelvis. 



The conjugate diameter of the brim is the distance from the median 

 point on the cephalic edge of the sacrum to the cephalic end of the 

 pubic symphysis. 



The obstetric conjugate diameter is the shortest distance from the 

 median point on the cephalic edge of the sacrum to the cephalic end of 

 the pubic symphysis. 



The diagonal conjugate diameter is the distance from the cephalic 

 end of the sacrum to the caudal end of the pubic symphysis. 



The obstetric conjugate diameter of the outlet is the distance from the 

 caudal end of the pubic symphysis to the caudal end of the sacrum. 



The transverse diameter is the width of the brim between the 

 pectineal eminences. 



The pectineal oblique diameter is the distance from the pectineal 

 eminence on one side to the cephalic end of the sacro-iliac articulation 

 on the other side. 



The true oblique diameter is the greatest oblique distance from the 

 sacro-iliac articulation on one side to the brim of the pelvis on the 

 other side. 



