OBSTETRICS* 



Obstetrical Anatomy 



Name the soft organs concerned in obstetric anatomy. 

 Ovaries, uterus, vagina, vulva and mammae. 



What is the pelvis? Name the functions of the pelvis. How many 

 centres of ossification appear in its early formation? 



The pelvis is a bony framework at the posterior extremity of the 

 trunk, supporting the spinal colimm and resting upon the posterior 

 extremities. It contains, sustains and protects a portion of the 

 genito-urinary apparatus, as weU as the terminal portion of the 

 alimentary canal. It constitutes a most important fulcrum or fixed 

 point in various muscular movements and supplies a passageway for 

 the fcetus during the act of parturition. 



Five centres of ossification appear in each half in its early for- 

 mation; one for each of the three bones and two complementary 

 centres, one for the anterior spinous process and spine of the ileum, 

 the other for the ischial tuberosity. 



Make a drawing to show the normal position of the generative organs 

 of the mare. Show also the kidney, the bladder and the 

 rectum."!" 



State how the bones of the pelvis of the mare differ from those of (a) 

 the cow, (b) the sheep, (c) the goat, (d) the bitch, (e) the 

 cat. 



(a) The pelvis of the cow is longer and less vertical than in the 

 mare. Because of the greater curvature of the ischiopubie sym- 

 physis, the floor is concave. The pelvis of the cow is more cylindrical 

 and less conical than that of the mare. 



(b) and (c) The pelvis of the sheep and of the goat is about the 

 same as in the cow, except, of course, in size. The symphysis is 

 nearly rectilinear in its direction, and it ossifies at a very much 

 later period than in the cow or mare. 



(d) and (e) The marked angle formed by the sacrum and the 

 lumbar vertebrae diminishes the inlet of the pelvis. The direction 

 of the symphysis is rectilinear and the pelvic cavity is nearly 

 cylindrical. 



* Unless otherwise stated all questions relate to the horse, 

 t There are no illustrations in this book, but this drawing would seem com- 

 paratively simple. 



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