Fetal Skull Anatomy

Flashcards about the fetal skull, sutures, and fontanelles.

Sinciput

The most anterior portion of the fetal skull; the brow.

Occiput

The region of the fetal skull located at the posterior part of the head.

Parietal Bones

Located on either side of the skull and ossify to form parietal eminences.

Frontal Bones

Ossify to form the frontal eminence of each bone and shape the forehead/sinciput.

Ossification

The natural process of bone formation/hardening.

Lambdoid Suture

Separates the occipital bone from the two parietal bones.

Sagittal Suture

Lies between the two parietal bones.

Coronal Suture

Separates the two frontal bones from the parietal bones, passing from one temple to another.

Frontal Suture

Separates the two frontal bones.

Moulding

The change in shape of the fetal head that takes place during its passage through the pelvis and birth canal during labour/birth.

Anterior Fontanelle (Bregma)

Diamond or kite shaped fontanelle which closes at approximately 18 months of age.

Posterior Fontanelle (Lambda)

Small, triangular shape fontanelle which closes at approximately 6 weeks of age.

Suboccipitobregmatic

From neck to bregma (top of head). Diameter 9.5cm

Suboccipito-frontal

Neck to forehead. Diameter 10cm

Occupitofrontal

Under nose to occiput (back of head). Diameter 11.5cm

Mento-vertical

Chin to saggital suture. Diameter: 14cm

Submentovertical

Chin to vertex (topish back of head). Diameter 11.5cm

Submentobregmatic

Chin to bregma (top of head). Diameter 9.5cm