Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Scientific Basis of Midwifery > Foetal Skull > Flashcards

Foetal Skull Flashcards

1
Q

Describe the skull

A
  • Consists of 29 bones
  • Ovoid shaped
  • Consists of vault, base and face
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the skull bones divided into?

A
  • Vault
  • 2 frontal
  • 2 parietal
  • 2 temporal
  • 1 occipital
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the vault?

A

Dome-shaped part between the orbital ridges and the nape of the neck

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the occipital bone

A
  • Lies at the back of the head

- Ossification centre = occipital protuberance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the parietal bones

A
  • Lie on either side of the skull

- Ossification centres = parietal eminences

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the frontal bones

A
  • Form the forehead and sinciput

- Ossification centres = frontal eminences

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the base?

A

Firmly united bone protecting the vital centres of the medulla oblongata

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the face

A
  • 14 small bones
  • Firmly united and non-compressible
  • Extends from orbital ridges to neck
  • The point between the eyebrows in known as the glabella
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 4 regions of the foetal skull?

A
  1. Forehead/ Sinciput region (brow)
  2. Vertex
  3. Occiput
  4. Face
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the forehead/ sinciput region

A

Extends from the anterior fontanelle and the coronal suture to the orbital ridges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the vertex

A

Bounded by the posterior fontanelle, the 2 parietal eminences and the anterior fontanelle
- Vertex positing = head first

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the occiput

A
  • Lies between the foramen magnum and posterior fontanelle

- The part below the occipital protuberance is known as the sub-occipital region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Name 3 landmarks

A
  1. Occipital protuberance
  2. Mentum (chin)
  3. Glabella
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a suture?

A
  • The cranial joints formed when 2 bones meet
  • Soft, fibrous tissue where ossification is not complete
  • Allows moulding during labour and birth and expansion of brain development
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is ossification?

A

The hardening of the bones of the vault from the ossification centre outwards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 4 sutures called?

A
  1. Frontal - between 2 halves of the frontal bone
  2. Sagittal - between 2 parietal bones
  3. Lamboidal - separates occipital bone and 2 parietal bones
  4. Coronal - separates front bones from parietal bones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a fontanelle?

A

A membranous non-ossified area where 2 or more sutures meet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe the anterior fontanelle

A
  • Diamond/kite shaped
  • Formed by junction of sagittal, coronal and frontal sutures
  • Larger than the posterior fontanelle
  • Closes at 18 months of age
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What should the anterior fontanelle feel like during a VE?

A
  • 4 sutures felt emanating from the fontanelle
  • Demonstrates de-flexed head
  • Alerts practitioners to larger diameter coming through pelvis
  • Indicates direct occipital position
20
Q

What is another name for the anterior fontanelle?

A

Bregma

21
Q

Describe the posterior fontanelle

A
  • Triangular
  • Smaller than the anterior fontanelle
  • Formed by junction of lamboidal and sagittal sutures
  • Closes at 6 weeks
22
Q

What should the posterior fontanelle feel like during a VE?

A
  • 3 sutures felt emanating from fontanelle
  • Well-flexed head position
  • Smaller diameter presenting
  • Indicated occipitoanterior position
23
Q

What is another name for the posterior fontanelle?

A

Lambda

24
Q

What are the 9 diameters of the foetal skull?

A
  1. Suboccipitobregmatic
  2. Suboccipitofrontal
  3. Occipitofrontal
  4. Mentovertical
  5. Submentovertical
  6. Submentobregmatic
  7. Biparietal
  8. Bisacromial
  9. Bitrochanteric
25
Q

Describe the suboccipitobregmatic diameter

A
  • Below the occipital bone to the centre of the anterior fontanelle
  • 9.5cm
26
Q

Describe the suboccipitfrontal diameter

A
  • Below the occipital bone to the centre of the frontal bone/ suture
  • 10cm
27
Q

Describe the occipitofrontal diameter

A
  • The occipital protuberance to the glabella (frontal bone)

- 11.5cm

28
Q

Describe the mentovertical diameter

A
  • From the point of the chin straight upwards to the highest point on the vertex
  • 13.5cm
29
Q

Describe the submentovertical diameter

A
  • From the point where the chin meets the neck, straight upwards to the highest point on the vertex
  • 11.5cm
30
Q

Describe the submentobregmatic diameter

A
  • From the point where the chin meets the neck to the centre of the bregma
  • 9.5cm
31
Q

Describe the biparietal diameter

A
  • Stretched between the parietal eminences and is the engaging/crowning diameter
  • 9.5cm
32
Q

Describe the bisacromial diameter

A
  • Stretched between the acromion processes on the 2 shoulder blades
  • Articulation of the clavicles on the sternum may reduce this diameter slightly
  • 12cm
33
Q

Describe the bitrochanteric diameter

A
  • Stretches between the greater trochanters of the femurs
  • This is the presenting diameter in breech presentation
  • 10cm
34
Q

What are the 3 main types of presentation?

A
  1. Vertex
  2. Face
  3. Brow
35
Q

Describe vertex presentation

A
  • When head is well-flexed, sub-occipitobregmatic and biparietal diameters present
  • Sub-occipitofrontal diameter distends vaginal orifice
  • When head is deflexed, presenting diameters are occipitofrontal and biparietal
  • This arises when occiput is in posterior position
  • If this remains, occipitofrontal diameter distends vaginal orifice
36
Q

Describe face presentation

A
  • When head is completely extended, presenting diameters are submentobregmatic and bitemporal
  • Submentovertical diameter distends the vaginal orifice
37
Q

Describe brow presentation

A
  • Occurs when head is partially extended and mentovertical and bitemporal diameters present
  • Vaginal birth unlikely
38
Q

What are the 5 main possible presenting parts?

A
  1. Cephalic
  2. Breech
  3. Face
  4. Brow
  5. Shoulder
39
Q

Define moulding

A

The change in shape of the foetal head that takes place during its passage through the birth canal

40
Q

Why does moulding occur?

A
  • Bones of vault allow a slight degree of bending as they are soft and able to override sutures
  • Results from pelvic girdle pressure
  • Enables skull to alter shape and negotiate pelvis
  • Diameters can be increased/decreased up to 1.5cm
  • Frontal bones pushed to anterior edge of 2 parietal bones and occipital bone pushed under parietal bones
41
Q

What relevance do sutures and fontanelles have to practice?

A
  • To diagnose position of foetal head in labour
  • Check foetal head for moulding
  • Placing SE clip away from fontanelle
  • Position is important for fixing ventouse cup
42
Q

What is the favourable position for labour?

A 
Lie - longitudinal
Presentation - cephalic
Position - left/right occipitoanterior
Attitude - flexion
Denominator - occiput
Presenting part - posterior part of anterior parietal bone
43
Q

Why is it important for the midwife to understand normal labour?

A
  • To detect normal progresses of labour
  • Awareness of abnormal mechanisms
  • Aids delivery technique
  • Assists in recognising shoulder dystocia
44
Q

What does it mean if the fontanelle is sunk/ raised?

A 
Sunk = dehydrated
Raised = infection
45
Q

What may cause bleeding in the great cerebral vein?

A

A tear in the tentorium cerebella

46
Q

What is a caput succedaneum?

A
  • Swelling caused by fluid under the skin
  • Caused by pressure on the cervix at delivery
  • Resolves within 24 hours
47
Q

What is a cephalic haematoma?

A
  • Swelling seen over 1 of 2 parietal bones
  • Results in blood escaping from ruptured blood vessels between skull and periosteum
  • Caused by trauma during delivery (e.g. forceps, ventouse)
  • Occurs a few hours after birth up to 18 months

Scientific Basis of Midwifery (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions