58 



OBSTETRICS. 



Cephalic presentations, including vertex and face. 

 Breech or pelvic, including the hips and loins. 

 Inferior extremities, including the knees and feet. \ Churchil 

 Superior extremities, including the shoulder, elbow 

 and hand. 



Others, such as the back, belly, and sides, are so exceedingly rare, 

 that it is not considered advisable to burden the student's mind with 

 them, particularly as their treatment is the same as that of shoulder 

 presentations. 



The diagnosis of these different presentations may be described 

 in general terms, as follows, viz. : 



Of the head, by its hardness, by the presence of sutures and fon- 

 tanel les, and by its shape. 



Of the^^ce, by its irregular shape, by the orbits of the eyes, by 

 the nose, mouth, &c. 



Of the breech, by its softness, by the nates, organs of generation, 

 tubera ischii, and often by the meconium, by t^ single prominence 

 of the OS coccygis, and by the sphincter ani muscle, which con- 

 tracts when irritated by the finger. 



Of the knee, by its rounded form, and by the condyles of the 

 femur, and perhaps by the patella. 



Of the^oo^, by its length, shape, position at right angles to the leg, 

 by the equal length of the toes, the heel, &c. 



Of the shoulder, by its rounded shape, by the clavicle, the spine of 

 the scapula, the axilla, ribs, &c. 



Of the elhov), by its sharpness, produced by the olecranon process. 



Of the hand, by its shortness, the thumb and fingers, palmar and 

 dorsal aspect, &c. 



In regard to the positions, it is customary to note the relation be- 

 tween some point of the presenting part, and some other point in the 

 brim of the pelvis ; for instance, the first position of the vertex is that 

 in which the posterior fontanelle is found behind the left acetabulum. 

 The different positions will be spoken of in treating of the various 

 presentations. 



MECHANISM OF LABOUR. 



" When the long axis of the child's body corresponds with that of 

 the uterus, the child (provided the passages are round) can be born in 

 that position ; it matters little, so far as the labour is concerned, 

 which extremity of child presents, so long as this is the case ; but 

 where the long axis of the body does not correspond with that of the 

 uterus, the child must evidently lie more or less across, and will pre- 

 sent, with the arm or shoulder, a position in which it cannot be born. 

 Tn stating this, we wish it to be understood, that we merely refer to 

 the full grown living fcetus, and not to one which is premature, or 

 which has been some time dead in the uterus, as these follow no rule 



