Flexion of Anterior Limbs at Carpus 757 



the operator should take the further precaution to see that the 

 elbow is completely extended, before any traction is applied 

 to other- portions of the fetus, because, until this is done, the 

 position remains such that expulsion cannot readily occur. 



3. Flexion of the Anterior I^imbs at the Carpus. 



This obstacle to birth occurs chiefly in the calf and foal, and to a 

 lesser extent in the lamb and kid, but in these cases it is very rare 

 and of less significance. In carnivora and the sow the condition is 

 not present, or not of moment as a cause of dystokia, because the 

 limbs are short and may readily fold backward and permit the 

 head to present alone. 



Fig. 131. Fi,axDRE OF THB Anterior Limbs at the Carpus. 

 (St. Cyr.) 



In such cases the metacarpus is flexed upon the radius, the ra- 

 dius upon the humerus, and the humerus upon the scapula, so 

 that the entire limb is folded and the shoulders are pushed back 

 upon the chest, thus greatly increasing the perpendicular and 

 transverse diameters of the fetal body in the region of the chest, 

 and offering a very great obstacle to its expulsion, which is 

 greatly heightened by the impaction of the carpus in the pelvic 

 canal, or in front of or beneath the pubic brim. 



