|Latin||Articulatio fibrosa, junctura fibrosa|
These are fixed joints where bones are united by a layer of white fibrous tissue of varying thickness.
Such immovable joints are also referred to as synarthroses.
Most fibrous joints are also called "fixed" or "immovable".
These joints have no joint cavity and are connected via fibrous connective tissue.
The skull bones are connected by fibrous joints called sutures.
In fetal skulls the sutures are wide to allow slight movement during birth.
They later become rigid (synarthrodial).
Syndemoses are slightly moveable (amphiarthrodial).
The distal tibiofibular joint is another example.
This section is about joints in the bones of the skull.
For stitches holding tissues together, see Surgical suture.
For natural structures of a wide range of animals, see Suture (anatomy).
For other uses, see Suture (disambiguation).
A suture is a type of fibrous joint that is only found in the skull (cranial suture).
The bones are bound together by Sharpey's fibres.
These joints are synarthroses.
It is normal for many of the bones of the skull to remain unfused at birth.
The fusion of the skull's bones before birth is known as craniosynostosis.
The term "fontanelle" is used to describe the resulting "soft spots".
In old age, cranial sutures may ossify (turn to bone) completely.
The joints between the teeth and jaws (gomphoses) and the joint between the mandible and the cranium, the temporomandibular joint, form the only non-sutured joints in the skull.
Types of sutures
- Plane sutures – edges of the bones are flush with each other as in a normal butt joint. Eg: Internasal suture.
- Limbous sutures – edges are bevelled so the plane of the suture is sloping as in a mitre joint. Eg: Temporo-parietal suture.
- Schindylesis – formed by two bones fitting into each other similar to a bridle joint. Eg: Palatomaxillary suture.
- Denticulate sutures – the edges slot into each other as in a finger joint. Eg: Lambdoid suture.
- Serrate sutures – similar to a denticulate suture but the interlocking regions are serrated rather than square. Eg: Coronal suture.
List of sutures
Most sutures are named for the bones they articulate, but some have special names of their own.
Visible from the side
- Coronal suture – between the frontal and parietal bones
- Lambdoid suture – between the parietal and occipital bones and continuous with the occipitomastoid suture
- Occipitomastoid suture – between the occipital and temporal bones and continuous with the lambdoid suture
- Sphenofrontal suture
- Sphenoparietal suture
- Sphenosquamosal suture
- Sphenozygomatic suture
- Squamosal suture – between the parietal and the temporal bone
- Zygomaticotemporal suture
- Zygomaticofrontal suture
Visible from the front or above
- Frontal suture / Metopic suture – between the two frontal bones, prior to the fusion of the two into a single bone
- Sagittal suture – along the midline, between parietal bones
Visible from below or inside
Credits to the contents of this page go to the authors of the corresponding Wikipedia page: en.wikipedia.org/wiki/Fibrous joint.