76 



ANATOMY FOR NURSES 



[Chap. V 



the large (false), and small (true) pelvis. The narrowed bony 

 ring which is the dividing line is spoken of as the brim of the pelvis, 

 the ilio-pedineal line, and the strait. The large pelvis is all that 

 expanded portion of the pelvis situated above the brim ; it forms 

 an incomplete or false basin. The small pelvis is all that portion 

 situated below the brim. Its cavity is a little wider in every direc- 

 tion than the brim itself, while the large pelvis is a great deal wider. 

 The small bony pelvis is a basin with incomplete walls of bone, 



. Fig. 55. — Male Pelvis. 



the bottom of which is composed of the softer tissues, muscles, 

 and ligaments. The opening of the small pelvis, i.e. the space 

 just above the brim, is called the inlet, and the opening below is 

 called the inferior strait, or outlet. 



The female pelvis differs from that of the male in those particu- 

 lars which render it better adapted to pregnancy and parturition. 

 It is more shallow than the male pelvis, but wider.in every direction. 

 The inlet and outlet are larger, the bones are lighter and smoother, 

 and the coccyx is more movable. As can be seen by looking at 

 Fig. 54 and Fig. 55 a distinctive anatomical difference is that 

 the sub-pubic angle in a male is less than a right angle, and in the 

 female it is greater than a right angle. 



