fetal skull

Question 1

the bones that comprise the fetul skull form in two ways

Answer 1

The face is initially formed from cartilage which cover the course of fetal
development ossifies so that at term the face is almost completely ossified & facial
bones are fused
The bones of the vault originate from membrane and are more pliable & flatter, this
facilitates fetal passage through the bony structures of the maternal pelvis

Question 2

three main sections of the skull

Answer 2

face - orbital ridges of the eyes and the chin
base - chin to nape of neck
vault - orbital ridges of eyes to the nape of the neck

Question 3

smallness of the face is due to …

Answer 3

rudimentary development of the maxillae mandible and parasol sinuses . nose lies almost entirely between the orbits

Question 4

the vault

Answer 4

Only movable part of the skull
Multiple bones – not fused
Formation originates from membranes – this
makes the bones flatter

Question 5

frontal bone

Answer 5

form the forehead in the foetus the frontal bone is in two halves , which fuse into single bone after the age of eight

Question 6

parietal bone

Answer 6

lie on either side of the skull and occupy most of the skull

Question 7

occipital bone

Answer 7

form the back of the skull and part of its base joins with cervical vertebrae

Question 8

temporal bone

Answer 8

one on each side of the head closest to the ear

Question 9

the sutures

Answer 9

These are membranous lines found at the
junction between the bones of the vault.
There are four important sutures on the vault
where ossification has not been completed

Question 10

4 main sutures

Answer 10

frontal
saggital
coronal
lambdoidal

Question 11

define function of the frontal , coronal
saggiato and lambdoidal suture

Answer 11

The Frontal Suture: Separates the two frontal bones, it extends from
the root of the nose to the bregma.
The Coronal Suture: Separates the frontal and the parietal bones.
Sagittal Suture: Separates the two parietal bones.
Lambdoidal suture: Separates the occipital and the parietal bones

Question 12

when are fontanelles formed

Answer 12

where two or more sutures meet between the bones

Question 13

anterior fontanelle bregma

Answer 13

It is a diamond
shaped
membranous
space.
It has four angles
which correspond
with the entry of
each suture.
It is about 3-4cm
long and 1.5cm
wide.
It is a valuable aid
in vaginal
examination to
determining the
position.
Closes 18-24months
after birth

Question 14

posterior fontanelle bregma

Answer 14

It is a small triangular
membranous space.
It is felt on vaginal examination
during labour in a well flexed
head.
It closes at 6 weeks after birth.

Question 15

label the skull diagram

Answer 15

answer

Question 16

the scalp of the fetes consist of five layer what are they

Answer 16

The Skin
A subcutaneous tissue:
Contains blood vessels and hair
follicles.
Is the part where Caput
Succedaneum is formed.
A layer of Tendon – Galea
A loose layer of alveolar
tissue.
Limits movement of the
scalp over the skull.
The pericranium – is the periosteum of
the cranial bones which covers the outer
surface and is adherent to their edge.
Cephalhaematoma is limited to the
layer over the bones where it lays
because it is attached to the edge of the
bone.

Question 17

what is caput succedaneum

Answer 17

swelling appears at birth dissappears after a few days

Question 18

cephalhematoma

Answer 18

several hours after both , dissapears 6 weeks after birth

Question 19

moulding

Answer 19

during the passage through the birth canal , the head can be squeezed because of slight movement at the fontanelle and sutures and slight overriding of bones also occur

* Frontal bones slip under parietal bones 
* Parietal bones override each other Occipital bone slips under the parietal bone

Question 20

fetul skull diameters

Answer 20

practice

Question 21

parietal eminence

Answer 21

The site where intramembranous ossification
of the parietal bone begins

Question 22

attitude

Answer 22

Attitude - relationship between Fetal head and limbs to its body
* Flexed
* Deflexed
Hyper extended

Question 23

presentation

Answer 23

Presentation -which presenting part is leading determined by the part of the fetus in the lower uterine segment
* Face
* Brow
* Vertex
* Sinciput