Parietal bone

Function

Forms the bulk of the cranial vault roof and side walls, enclosing and protecting the parietal lobes of the brain. The internal surface is grooved by the middle meningeal vessels that supply the dura mater.

Landmarks

• Parietal tuber (eminence)
• Superior and inferior temporal lines
• Grooves for the middle meningeal artery
• Parietal foramen

Articulations (joints)

• Right parietal (sagittal suture)
• Frontal bone (coronal suture)
• Occipital bone (lambdoid suture)
• Temporal bone (squamosal suture)
• Sphenoid bone (greater wing)

Clinical relevance

The pterion — where parietal, frontal, temporal and sphenoid meet — overlies the middle meningeal artery; a blow here causes extradural haematoma. Parietal fractures risk tearing these vessels.