Anatomy of a Newborn Baby’s Skull

The cranium could appear to be one massive bone, nevertheless it’s manufactured from a number of main bones which can be linked collectively. The most important bones that compose the cranium embody:

2 frontal bones

2 parietal bones

1 occipital bone

These bony plates cowl the mind, and are held collectively by fibrous materials referred to as sutures.

What are sutures?

Sutures permit the bones to maneuver in the course of the beginning course of. They act like an growth joint. This enables the bone to enlarge evenly because the mind grows and the cranium expands. The result’s a symmetrically formed head. Some sutures lengthen to the brow, whereas others lengthen to the perimeters and again of the cranium. One suture in the midst of the cranium extends from the entrance of the top to the again. The most important sutures of the cranium embody:

Metopic suture. This extends from the highest of the top down the center of the brow, towards the nostril. The 2 frontal bone plates meet on the metopic suture.

Coronal suture. This extends from ear to ear. Every frontal bone plate meets with a parietal bone plate on the coronal suture.

Sagittal suture. This extends from the entrance of the top to the again, down the center of the highest of the top. The 2 parietal bone plates meet on the sagittal suture.

Lambdoid suture. This extends throughout the again of the top. Every parietal bone plate meets the occipital bone plate on the lambdoid suture.

If any of the sutures shut too early (fuse prematurely), there could also be no progress in that space. This will pressure progress to occur in one other space or path. This ends in an irregular head form (craniosynostosis).

What are fontanelles?

A fontanelle is the house between the bones of a child’s cranium the place the sutures intersect. There are 2 fontanelles. These areas are coated by robust membranes (dura) that defend the underlying smooth tissues and mind. The fontanelles embody:

Anterior fontanelle (additionally referred to as smooth spot). That is the junction the place the 2 frontal and 2 parietal bones meet. The anterior fontanelle stays smooth till about 18 months to 2 years of age. Healthcare suppliers can assess if there may be elevated intracranial stress by feeling the anterior fontanelle.

Posterior fontanelle. That is the junction of the 2 parietal bones and the occipital bone. The posterior fontanelle often closes first, earlier than the anterior fontanelle, in the course of the first a number of months of an toddler’s life.

As a result of the fontanelles are smooth early in life, it’s simple to take footage of a child’s mind with ultrasound.

On-line Medical Reviewer:
Anne Fetterman RN BSN

On-line Medical Reviewer:
Joseph Campellone MD

On-line Medical Reviewer:
Raymond Kent Turley BSN MSN RN

Date Final Reviewed:
8/1/2023