Suture (joint)

This article is about joints in the bones of the cranium. There is also an article about sutures as features of a wide range of animals. "Suture" also has other meanings in other contexts:

• Surgical suture, to describe stitches and other techniques for holding tissues together.
• Geology, to describe a certain type of boundary between layers of rock.

A suture is a type of fibrous joint which only occurs in the skull (or "cranium"). They are bound together by Sharpey's fibres. A tiny amount of movement is permitted at sutures, which contributes to the compliance and elasticity of the skull.

These joints are synarthroses.^[1]

It is normal for many of the bones of the skull to remain unfused at birth. If they are fused at birth, we speak of a craniosynostosis. The term "fontanelle" is used to describe the resulting "soft spots". The relative positions of the bones continue to change during the life of the adult (though less rapidly), which can provide useful information in forensics and archaeology. In old age, cranial sutures may ossify (turn to bone) completely.

List of sutures

Most sutures are named for the bones they articulate, but some have special names of their own.

Primarily visible from the side (norma lateralis)

• Coronal suture - between the frontal and parietal bones
• Lambdoid suture - between the parietal, temporal and occipital bones
• Occipitomastoid suture
• Parietomastoid suture
• Sphenofrontal suture
• Sphenoparietal suture
• Sphenosquamosal suture
• Sphenozygomatic suture
• Squamosal suture - between the parietal and the temporal bone
• Zygomaticotemporal suture
• Zygomaticofrontal suture

Primarily visible from front (norma frontalis) or above (norma verticalis)

• Frontal suture / Metopic suture - between the two frontal bones, prior to the fusion of the two into a single bone
• Sagittal suture - along the midline, between parietal bones

Primarily visible from below (norma basalis) or inside

• Frontoethmoidal suture
• Petrosquamous suture
• Sphenoethmoidal suture
• Sphenopetrosal suture

References

External links

• MedlinePlus Encyclopedia 002320
• Age at Death Estimation from Cranial Suture Closures
• http://commons.bcit.ca/biology/articulations/fibrous.html