Bregma

Last updated
Bregma
Kort-lang-skalle.gif
Superior view of the calvarium, bregma located at the intersection of the coronal and sagittal sutures.
  1. Coronal Suture
  2. Sagittal Suture
  3. Lambdoid Suture
(Lambda also visible at the intersection of the lambdoid suture by the sagittal suture.)
Details
Precursor Anterior fontanelle
System Skeletal system
Identifiers
Latin bregma
TA98 A02.1.00.016
TA2 418
FMA 264776
Anatomical terminology

The bregma is the anatomical point on the skull at which the coronal suture is intersected perpendicularly by the sagittal suture.

Contents

Structure

The bregma is located at the intersection of the coronal suture and the sagittal suture on the superior middle portion of the calvaria. [1] It is the point where the frontal bone and the two parietal bones meet. [1]

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. [2]

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. [3] [4] It may be identified by blunt scraping of the surface of the skull and washing to make the meeting point of the sutures clearer. [3]

Neonatal examination

Examination of an infant includes palpating the anterior fontanelle. [5] It should be flat, soft, and less than 3.5cm across. [5] 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). [6] This is strongly linked to more general growth. [6] 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. [6]

Etymology

The word "bregma" comes from the Ancient Greek βρέγμα (brégma), meaning the bone directly above the brain. [7]

Related Research Articles

<span class="mw-page-title-main">Skull</span> Bony structure that forms the head in vertebrates

The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone, however two parts are more prominent: the cranium and the mandible. In humans, these two parts are the neurocranium (braincase) and the viscerocranium that includes the mandible as its largest bone. The skull forms the anterior-most portion of the skeleton and is a product of cephalisation—housing the brain, and several sensory structures such as the eyes, ears, nose, and mouth. In humans, these sensory structures are part of the facial skeleton.

<span class="mw-page-title-main">Fontanelle</span> Anatomical feature of the infant human skull

A fontanelle is an anatomical feature of the infant human skull comprising soft membranous gaps (sutures) between the cranial bones that make up the calvaria of a fetus or an infant. Fontanelles allow for stretching and deformation of the neurocranium both during birth and later as the brain expands faster than the surrounding bone can grow. Premature complete ossification of the sutures is called craniosynostosis.

<span class="mw-page-title-main">Parietal bone</span> Bone in the human skull which, when joined together, forms the sides and roof of the cranium

The parietal bones are two bones in the skull which, when joined at a fibrous joint, form the sides and roof of the neurocranium. In humans, each bone is roughly quadrilateral in form, and has two surfaces, four borders, and four angles. It is named from the Latin paries (-ietis), wall.

<span class="mw-page-title-main">Craniosynostosis</span> Premature fusion of bones in the skull

Craniosynostosis is a condition in which one or more of the fibrous sutures in a young infant's skull prematurely fuses by turning into bone (ossification), thereby changing the growth pattern of the skull. Because the skull cannot expand perpendicular to the fused suture, it compensates by growing more in the direction parallel to the closed sutures. Sometimes the resulting growth pattern provides the necessary space for the growing brain, but results in an abnormal head shape and abnormal facial features. In cases in which the compensation does not effectively provide enough space for the growing brain, craniosynostosis results in increased intracranial pressure leading possibly to visual impairment, sleeping impairment, eating difficulties, or an impairment of mental development combined with a significant reduction in IQ.

<span class="mw-page-title-main">Levator palpebrae superioris muscle</span> Muscle in orbit that elevates upper eyelid

The levator palpebrae superioris is the muscle in the orbit that elevates the upper eyelid.

<span class="mw-page-title-main">Sagittal plane</span> Anatomical plane dividing the body into left and right

The sagittal plane is an anatomical plane that divides the body into right and left sections. It is perpendicular to the transverse and coronal planes. The plane may be in the center of the body and divide it into two equal parts (mid-sagittal), or away from the midline and divide it into unequal parts (para-sagittal).

Craniofacial surgery is a surgical subspecialty that deals with congenital and acquired deformities of the head, skull, face, neck, jaws and associated structures. Although craniofacial treatment often involves manipulation of bone, craniofacial surgery is not tissue-specific; craniofacial surgeons deal with bone, skin, nerve, muscle, teeth, and other related anatomy.

<span class="mw-page-title-main">Sagittal suture</span> Midline joint between the parietal bones of the skull

The sagittal suture, also known as the interparietal suture and the sutura interparietalis, is a dense, fibrous connective tissue joint between the two parietal bones of the skull. The term is derived from the Latin word sagitta, meaning arrow.

<span class="mw-page-title-main">Lambdoid suture</span> Connective tissue between the parietal bones and the occipital bone of the skull

The lambdoid suture is a dense, fibrous connective tissue joint on the posterior aspect of the skull that connects the parietal bones with the occipital bone. It is continuous with the occipitomastoid suture.

<span class="mw-page-title-main">Coronal suture</span> Connective tissue between the parietal bones and the frontal bone of the skull

The coronal suture is a dense, fibrous connective tissue joint that separates the two parietal bones from the frontal bone of the skull.

<span class="mw-page-title-main">Anterior longitudinal ligament</span> Ligament running down the front of the vertebral column

The anterior longitudinal ligament is a ligament that extends across the anterior/ventral aspect of the vertebral bodies and intervertebral discs the spine.

<span class="mw-page-title-main">Anterior superior iliac spine</span> Bony projection of the iliac bone

The anterior superior iliac spine (ASIS) is a bony projection of the iliac bone, and an important landmark of surface anatomy. It refers to the anterior extremity of the iliac crest of the pelvis. It provides attachment for the inguinal ligament, and the sartorius muscle. The tensor fasciae latae muscle attaches to the lateral aspect of the superior anterior iliac spine, and also about 5 cm away at the iliac tubercle.

<span class="mw-page-title-main">Confluence of sinuses</span> Venous sinus in the skull

The confluence of sinuses, torcular Herophili, or torcula is the connecting point of the superior sagittal sinus, straight sinus, and occipital sinus. It is below the internal occipital protuberance of the skull. It drains venous blood from the brain into the transverse sinuses. It may be affected by arteriovenous fistulas, a thrombus, major trauma, or surgical damage, and may be imaged with many radiology techniques.

<span class="mw-page-title-main">Superior sagittal sinus</span> Anatomical structure of the brain

The superior sagittal sinus, within the human head, is an unpaired area along the attached margin of the falx cerebri. It allows blood to drain from the lateral aspects of anterior cerebral hemispheres to the confluence of sinuses. Cerebrospinal fluid drains through arachnoid granulations into the superior sagittal sinus and is returned to venous circulation.

<span class="mw-page-title-main">Calcarine sulcus</span> Anatomical landmark in the brain of humans and other primates

The calcarine sulcus is an anatomical landmark located at the caudal end of the medial surface of the brain of humans and other primates. Its name comes from the Latin "calcar" meaning "spur". It is very deep, and known as a complete sulcus.

<span class="mw-page-title-main">Innermost intercostal muscle</span>

The innermost intercostal muscle is a layer of intercostal muscles. It may also be called the intima of the internal intercostal muscles. It is the deepest muscular layer of the thorax, with muscle fibres running vertically. It is present only in the middle of each intercostal space, and often not present higher up the rib cage. It lies deep to the plane that contains the intercostal nerves and intercostal vessels, and the internal intercostal muscles. The diaphragm is continuous with the innermost intercostal muscle.

<span class="mw-page-title-main">Carotid canal</span> Hole in the temporal bone in the skull for the internal carotid artery to enter the skull

The carotid canal is a passage in the petrous part of the temporal bone of the skull through which the internal carotid artery and its internal carotid (nervous) plexus pass from the neck into the cranial cavity.

<span class="mw-page-title-main">Anterior fontanelle</span> Fontanelle in human skull

The anterior fontanelle is the largest fontanelle, and is placed at the junction of the sagittal suture, coronal suture, and frontal suture; it is lozenge-shaped, and measures about 4 cm in its antero-posterior and 2.5 cm in its transverse diameter. The fontanelle allows the skull to deform during birth to ease its passage through the birth canal and for expansion of the brain after birth.

<span class="mw-page-title-main">Fibrous joint</span> Fixed joints between bones held together by dense, fibrous tissue

In anatomy, fibrous joints are joints connected by fibrous tissue, consisting mainly of collagen. These are fixed joints where bones are united by a layer of white fibrous tissue of varying thickness. In the skull, the joints between the bones are called sutures. Such immovable joints are also referred to as synarthroses.

<span class="mw-page-title-main">Calvaria (skull)</span> Top part of the skull

The calvaria is the top part of the skull. It is the superior part of the neurocranium and covers the cranial cavity containing the brain. It forms the main component of the skull roof.

References

PD-icon.svgThis article incorporates text in the public domain from page 135 of the 20th edition of Gray's Anatomy (1918)

  1. 1 2 "Skull, Scalp, and Meninges Overview". Imaging in Neurology, Part 1. AMIRSYS. 2016. pp. 288–291. doi:10.1016/B978-0-323-44781-2.50232-1. ISBN   978-0-323-44781-2.
  2. Gilroy, Anne M.; MacPherson, Brian R.; Wikenheiser, Jamie C.; Schuenke, Michael; Schulte, Erik; Schumacher, Udo (2020). Atlas of Anatomy. Anne M. Gilroy, Brian R. MacPherson, Jamie C. Wikenheiser, Markus M. Voll, Karl Wesker, Michael Based on: Schünke (4th ed.). New York: Thieme Medical Publishers. ISBN   978-1-68420-203-4. OCLC   1134458436.{{cite book}}: CS1 maint: date and year (link)
  3. 1 2 Carvey, Paul M.; Maag, Terrence J.; Lin, Donghui (1994). "13 - Injection of Biologically Active Substances into the Brain". Methods in Neurosciences. Vol. 21. Elsevier. pp. 214–234. doi:10.1016/B978-0-12-185291-7.50019-9. ISBN   978-0-12-185291-7. ISSN   1043-9471.
  4. Harley, Carolyn W.; Shakhawat, Amin M. D.; Quinlan, Meghan A. L.; Carew, Samantha J.; Walling, Sue G.; Yuan, Qi; Martin, Gerard M. (2018). "Chapter 19 - Using Molecular Biology to Address Locus Coeruleus Modulation of Hippocampal Plasticity and Learning: Progress and Pitfalls". Handbook of Behavioral Neuroscience. Vol. 28. Publisher. pp. 349–364. doi:10.1016/B978-0-12-812028-6.00019-7. ISBN   978-0-12-812028-6. ISSN   1569-7339.
  5. 1 2 Carreiro, Jane E. (2009-01-01). "8 - Labor, delivery and birth". An Osteopathic Approach to Children (2nd ed.). Churchill Livingstone. pp. 131–145. doi:10.1016/b978-0-443-06738-9.00008-3. ISBN   978-0-443-06738-9.{{cite book}}: CS1 maint: date and year (link)
  6. 1 2 3 Nikita, Efthymia (2017-01-01). "6 - Growth Patterns". Osteoarchaeology - A Guide to the Macroscopic Study of Human Skeletal Remains. Academic Press. pp. 243–267. ISBN   978-0-12-804021-8.{{cite book}}: CS1 maint: date and year (link)
  7. Liddell & Scott, Greek-English Lexicon

Additional images