DEPARTMENT OF SURGERY. 
615 
( c ) Constriction of the Transverse Diameter .—The cause of 
his constriction is about the same as those mentioned above 
md are generally common to certain breeds ; in such constric- 
;ions the lateral walls of the pelvic canal approximate, either 
3y the change in the conformation of the pubis and ischium, or 
3y their abnormal size. 
Animals of this conformation should not be used for breed- 
ng purposes, for either of the above mentioned conditions in- 
:reases the danger of dystokia and especially when bred to large 
n ales. 
(D) Fractures of the Pelvis. —The most common frac- 
:ures of the pelvis are those of the external angle of the ilium, 
md the least that of the two pubes and ischia. In the horse, 
i fracture of the ischium often results from a fall or a kick ; 
md occasionally a fracture of the shaft of the ilium (Fig. 24). 
which is usually done by crushing. Pelvic fractures in general 
ire caused either by a fall, a blow, or by crushing; and as there 
is no means by which they can be placed in their normal posi- 
FIG. 24. 
FRACTURE OF SHAFT OF THE ILIUM. 
