bregma
{{short description|Meeting point of the coronal suture and the sagittal suture of the skull}}
{{Infobox anatomy
| Name = Bregma
| Latin =bregma
| Image = Kort-lang-skalle.gif
| Caption = Superior view of the calvarium, bregma located at the intersection of the coronal and sagittal sutures.
(Lambda also visible at the intersection of the lambdoid suture by the sagittal suture.)
| Precursor =Anterior fontanelle
| System =Skeletal system
| Artery =
| Vein =
| Nerve =
| Lymph =
}}
The bregma is the anatomical point on the skull at which the coronal suture is intersected perpendicularly by the sagittal suture.
Structure
The bregma is located at the intersection of the coronal suture and the sagittal suture on the superior middle portion of the calvaria.{{Cite book|chapter-url=https://www.sciencedirect.com/science/article/pii/B9780323447812502321|title=Imaging in Neurology, Part 1|publisher=AMIRSYS|year=2016|isbn=978-0-323-44781-2|pages=288–291|language=en|chapter=Skull, Scalp, and Meninges Overview|doi=10.1016/B978-0-323-44781-2.50232-1}} It is the point where the frontal bone and the two parietal bones meet.
= Development =
The bregma is known as the anterior fontanelle during infancy. The anterior fontanelle is membranous and closes in the first 18-36 months of life.{{Cite book|last1=Gilroy|first1=Anne M.|url=https://www.worldcat.org/oclc/1134458436|title=Atlas of Anatomy|last2=MacPherson|first2=Brian R.|last3=Wikenheiser|first3=Jamie C.|last4=Schuenke|first4=Michael|last5=Schulte|first5=Erik|last6=Schumacher|first6=Udo|publisher=Thieme Medical Publishers|others=Anne M. Gilroy, Brian R. MacPherson, Jamie C. Wikenheiser, Markus M. Voll, Karl Wesker, Michael Based on: Schünke|year=2020|isbn=978-1-68420-203-4|edition=4th|location=New York|oclc=1134458436}}
Clinical significance
= Cleidocranial dysostosis =
In the birth defect cleidocranial dysostosis, the anterior fontanelle never closes to form the bregma.
= Surgical landmark =
The bregma is often used as a reference point for stereotactic surgery of the brain.{{Cite book|last1=Carvey|first1=Paul M.|chapter-url=https://www.sciencedirect.com/science/article/pii/B9780121852917500199|title=Methods in Neurosciences|last2=Maag|first2=Terrence J.|last3=Lin|first3=Donghui|publisher=Elsevier|year=1994|isbn=978-0-12-185291-7|volume=21|pages=214–234|chapter=13 - Injection of Biologically Active Substances into the Brain|doi=10.1016/B978-0-12-185291-7.50019-9|issn=1043-9471}}{{Cite book|last1=Harley|first1=Carolyn W.|chapter-url=https://www.sciencedirect.com/science/article/pii/B9780128120286000197|title=Handbook of Behavioral Neuroscience|last2=Shakhawat|first2=Amin M. D.|last3=Quinlan|first3=Meghan A. L.|last4=Carew|first4=Samantha J.|last5=Walling|first5=Sue G.|last6=Yuan|first6=Qi|last7=Martin|first7=Gerard M.|publisher=Publisher|year=2018|isbn=978-0-12-812028-6|volume=28|pages=349–364|chapter=Chapter 19 - Using Molecular Biology to Address Locus Coeruleus Modulation of Hippocampal Plasticity and Learning: Progress and Pitfalls|doi=10.1016/B978-0-12-812028-6.00019-7|issn=1569-7339}} It may be identified by blunt scraping of the surface of the skull and washing to make the meeting point of the sutures clearer.
= Neonatal examination =
Examination of an infant includes palpating the anterior fontanelle.{{Cite book|last=Carreiro|first=Jane E.|chapter-url=https://www.sciencedirect.com/science/article/pii/B9780443067389000083|title=An Osteopathic Approach to Children|date=2009-01-01|publisher=Churchill Livingstone|isbn=978-0-443-06738-9|edition=2nd|pages=131–145|language=en|chapter=8 - Labor, delivery and birth|doi=10.1016/b978-0-443-06738-9.00008-3}} It should be flat, soft, and less than 3.5cm across. A sunken fontanelle indicates dehydration, whereas a very tense or bulging anterior fontanelle indicates raised intracranial pressure.
= Height assessment =
Cranial height is defined as the distance between the bregma and the midpoint of the foramen magnum (the basion).{{Cite book|last=Nikita|first=Efthymia|chapter-url=https://www.sciencedirect.com/science/article/pii/B9780128040218000061|title=Osteoarchaeology - A Guide to the Macroscopic Study of Human Skeletal Remains|date=2017-01-01|publisher=Academic Press|isbn=978-0-12-804021-8|pages=243–267|language=en|chapter=6 - Growth Patterns}} This is strongly linked to more general growth. This can be used to assess the general health of a deceased person as part of an archaeological excavation, giving information on the health of a population.
Etymology
The word "bregma" comes from the Ancient Greek βρέγμα (brégma), meaning the bone directly above the brain.Liddell & Scott, Greek-English Lexicon
References
{{Gray's}}
{{Reflist}}
Additional images
File:Slide3ROM.JPG|The bregma, human skull.
External links
{{Commons category|Bregma}}
- {{NormanAnatomy|lesson1}}
{{Sutures}}
{{Portal bar|Anatomy}}
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