Parietal Bones

Definition

The parietal bones are a pair of flat, irregularly shaped bones that form the upper and middle portions of the sides and roof of the skull. They are an essential component of the cranium, providing protection for the brain and contributing to the overall structure and shape of the head.

5 Must Know Facts For Your Next Test

1. The parietal bones meet at the sagittal suture, which runs from the front to the back of the skull.
2. The parietal bones contribute to the formation of the coronal suture, which connects the frontal and parietal bones.
3. During development, the parietal bones are separated by the posterior fontanel, which eventually closes as the skull matures.
4. The parietal bones provide attachment points for several muscles, including the temporalis and sternocleidomastoid muscles.
5. Injuries or abnormalities affecting the parietal bones can lead to conditions like craniosynostosis, in which the sutures fuse prematurely.

Review Questions

• Describe the location and function of the parietal bones within the skull.
  • The parietal bones are a pair of flat, irregularly shaped bones that form the upper and middle portions of the sides and roof of the skull. They are an essential component of the cranium, providing protection for the brain and contributing to the overall structure and shape of the head. The parietal bones meet at the sagittal suture and also contribute to the formation of the coronal suture, which connects the frontal and parietal bones.
• Explain the role of the parietal bones in the development and growth of the skull.
  • During infant development, the parietal bones are separated by the posterior fontanel, a soft, membranous gap that allows the skull to change shape during childbirth and early growth. As the skull matures, the posterior fontanel eventually closes, and the parietal bones fuse together. The parietal bones also provide attachment points for muscles that facilitate the movement and development of the skull, such as the temporalis and sternocleidomastoid muscles.
• Discuss the potential consequences of abnormalities or injuries affecting the parietal bones.
  • Injuries or abnormalities affecting the parietal bones can lead to various conditions, such as craniosynostosis, in which the sutures fuse prematurely. This can result in an abnormal skull shape and potentially impede brain development. Additionally, the parietal bones' role in providing protection for the brain means that any trauma or pathological changes to these bones could have serious implications for the overall health and functioning of the central nervous system.

Related terms

Cranium:

The cranium is the bony structure that forms the upper part of the skull, enclosing and protecting the brain.

Sutures:

Sutures are the fibrous joints that connect the bones of the skull, allowing for growth and development of the head.

Fontanels: Fontanels are the soft, membranous gaps between the bones of the infant skull that allow for the skull to change shape during childbirth and early development.