Mastoid fontanelle

General Information
Latin	fonticulus mastoideus
Greek
TA98
TA2
FMA
Details
System	Skeletal system
Artery
Vein
Nerve
Lymphatic drainage
Precursor	Mesenchyme
Function
Identifiers
Clinical significance
Notes

The mastoid fontanelle is a small, membranous gap located at the junction of the temporal bone, parietal bone, and occipital bone in the infant skull. It is one of the several fontanelles present in the neonatal skull, which allow for the growth and expansion of the brain during early development.

Anatomy

The mastoid fontanelle is situated posterior to the ear and is bordered by the squamous part of the temporal bone, the mastoid process, and the lambdoid suture. It is one of the two posterolateral fontanelles, the other being the sphenoidal fontanelle.

Function

Fontanelles, including the mastoid fontanelle, serve several important functions in the developing infant. They allow for the skull to be flexible during birth, facilitating passage through the birth canal. Additionally, they accommodate the rapid growth of the brain during the first year of life.

Closure

The mastoid fontanelle typically closes by the end of the second year of life as the cranial bones fuse together. The timing of closure can vary among individuals, but it generally occurs after the closure of the anterior fontanelle.

Clinical significance

In some cases, the mastoid fontanelle may remain open longer than usual, which can be indicative of certain medical conditions such as hydrocephalus or congenital hypothyroidism. It is important for pediatricians to monitor the closure of fontanelles as part of routine infant health assessments.

See also

• Fontanelle
• Anterior fontanelle
• Posterior fontanelle
• Sphenoidal fontanelle

External links

• [Link to additional resources]