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[[Anatomy]] > [[Gray's Anatomy|Gray's Anatomy of the Human Body]] > III. [[Syndesmology]] > 5c. Articulations of the Vertebral Column with the Cranium


[[Anatomy]] > [[Gray's Anatomy| Gray's Anatomy of the Human Body]] > III. Syndesmology > 5c. Articulations of the Vertebral Column with the Cranium
[[Henry Gray]] (1821–1865). ''Anatomy of the Human Body''. 1918.


=='''Articulations of the Vertebral Column with the Cranium'''==
The ligaments connecting the [[vertebral column]] with the [[cranium]] are grouped into two sets:
* Those uniting the [[atlas]] (C1 vertebra) with the [[occipital bone]] 
* Those connecting the [[axis]] (C2 vertebra) with the occipital bone
===''Articulation of the Atlas with the Occipital Bone'' (''articulatio atlantoöccipitalis'')===


[[Henry Gray]] (1821–1865). Anatomy of the Human Body.  1918.  
This joint consists of a pair of [[condyloid joints]] between the [[occipital condyles]] and the [[superior articular facets]] of the atlas.
 
=='''Articulations of the Vertebral Column with the Cranium'''==
===Ligaments of the Atlanto-occipital Joint===
   
 
The ligaments connecting the vertebral column with the cranium may be divided into two sets: those uniting the atlas with the occipital bone, and those connecting the axis with the occipital bone.   
* Two [[Articular capsules]]
* [[Anterior atlanto-occipital membrane]]
* [[Posterior atlanto-occipital membrane]]
* Two [[Lateral atlanto-occipital ligaments]]
 
===='''Articular Capsules'''====
''(capsulæ articulares; capsular ligaments)''  
Thin and loose capsules enclosing each [[atlanto-occipital joint]], connecting the occipital condyles to the articular surfaces of the atlas.
 
===='''Anterior Atlanto-occipital Membrane'''====
''(membrana atlantoöccipitalis anterior)''  
[[File:Gray304.png|thumb|Anterior atlanto-occipital membrane (Gray 304)]]
 
A broad, dense fibrous membrane connecting the anterior margin of the [[foramen magnum]] to the anterior arch of the atlas. It is continuous laterally with the articular capsules and strengthened medially by a thick cord connecting the [[basilar part of the occipital bone]] to the anterior tubercle of the atlas.
 
* ''Anterior relation'': [[Rectus capitis anterior muscle]]  
* ''Posterior relation'': [[Alar ligaments]]


==='''Articulation of the Atlas with the Occipital Bone (''articulatio atlantoöccipitalis'')'''===
===='''Posterior Atlanto-occipital Membrane'''====
The articulation between the atlas and the occipital bone consists of a pair of condyloid joints. The ligaments connecting the bones are: 
''(membrana atlantoöccipitalis posterior)''
[[File:Gray305.png|thumb|Posterior atlanto-occipital membrane (Gray 305)]]


Two Articular Capsules.  
A thin, broad membrane attached above to the posterior margin of the foramen magnum and below to the posterior arch of the atlas. Defective laterally to accommodate the [[vertebral artery]] and [[suboccipital nerve]].


The Posterior Atlantoöccipital membrane. 
* ''Anterior relation'': [[Dura mater]] of the [[vertebral canal]] 
* ''Posterior relation'': [[Rectus capitis posterior minor]] and [[Obliquus capitis superior]]


The Anterior Atlantoöccipital membrane.  
===='''Lateral Atlanto-occipital Ligaments'''====
These are thickened portions of the articular capsule reinforced by fibrous bands. They extend from the [[jugular processes]] of the occipital bone to the bases of the transverse processes of the atlas.


Two Lateral Atlantoöccipital.
===='''Synovial Membranes'''====
Each atlanto-occipital joint contains a synovial membrane. Occasionally, they communicate with the synovial cavity behind the [[odontoid process]] of the [[axis]].


==== '''The Articular Capsules (''capsulœ articulares; capsular ligaments'')''' ====
===='''Movements of the Atlanto-occipital Joint'''====
The articular capsules surround the condyles of the occipital bone, and connect them with the articular processes of the atlas: they are thin and loose. 
The permitted movements include:


==== '''The Anterior Atlantoöccipital Membrane''' ====
* '''Flexion and Extension''': e.g., nodding "yes"
'''(''membrana atlantoöccipitalis anterior; anterior atlantoöccipital ligament'') (Fig. 304)''
* '''Lateral Flexion''': slight movement to one side
The anterior atlantoöccipitalis membrane is broad and composed of densely woven fibers, which pass between the anterior margin of the foramen magnum above, and the upper border of the anterior arch of the atlas below; laterally, it is continuous with the articular capsules; in front, it is strengthened in the middle line by a strong, rounded cord, which connects the basilar part of the occipital bone to the tubercle on the anterior arch of the atlas. This membrane is in relation in ''front'' with the Recti capitis anteriores, ''behind'' with the alar ligaments. 


==== '''The Posterior Atlantoöccipital Membrane''' ====
**Muscles involved**:
'''(''membrana atlantoöccipitalis posterior; posterior atlantoöccipital ligament'') (Fig. 305)''' 
The posterior atlantoöccipital membrane, broad but thin, is connected above, to the posterior margin of the foramen magnum; below, to the upper border of the posterior arch of the atlas. On either side this membrane is defective below, over the groove for the vertebral artery, and forms with this groove an opening for the entrance of the artery and the exit of the suboccipital nerve. 
The free border of the membrane, arching over the artery and nerve, is sometimes ossified. The membrane is in relation, ''behind'' with the Recti capitis posteriores minores and Obliqui capitis superiores; in ''front'' with the dura mater of the vertebral canal, to which it is intimately adherent. 


==== '''The Lateral Ligaments''' ====
* '''Flexion''': [[Longus capitis]], [[Rectus capitis anterior]]
The lateral ligaments are thickened portions of the articular capsules, reinforced by bundles of fibrous tissue, and are directed obliquely upward and medialward; they are attached above to the jugular processes of the occipital bone, and below, to the bases of the transverse processes of the atlas. 
* '''Extension''': [[Rectus capitis posterior major]], [[Rectus capitis posterior minor]], [[Obliquus capitis superior]], [[Semispinalis capitis]], [[Splenius capitis]], [[Sternocleidomastoid]], [[Trapezius]] (upper fibers)
* '''Lateral flexion''': [[Rectus capitis lateralis]], assisted by [[Trapezius]], [[Semispinalis capitis]], [[Splenius capitis]], and [[Sternocleidomastoid]] (same side)


==== '''Synovial Membranes''' ====
===''Ligaments Connecting the Axis with the Occipital Bone''===
There are two synovial membranes: one lining each of the articular capsules. The joints frequently communicate with that between the posterior surface of the odontoid process and the transverse ligament of the atlas. 


==== '''Movements''' ====
These include:
The movements permitted in this joint are ('<nowiki/>'''a'<nowiki/>''') flexion and extension, which give rise to the ordinary forward and backward nodding of the head, and ('<nowiki/>'''b'''') slight lateral motion to one or other side. 
''[[Flexion]]'' is produced mainly by the action of the Longi capitis and Recti capitis anteriores. 
''[[extension]]'' by the Recti capitis posteriores major and minor, the Obliquus superior, the Semispinalis capitis, Splenius capitis, Sternocleidomastoideus, and upper fibers of the Trapezius. 
The Recti laterales are concerned in the ''[[lateral movement]]'' assisted by the Trapezius, Splenius capitis, Semispinalis capitis, and the Sternocleidomastoideus of the same side, all acting together. 


<nowiki/>'''<nowiki/>'''
* [[Membrana tectoria]]
* [[Alar ligaments]]
* [[Apical ligament of the dens]]


=== '''ligaments Connecting the Axis with the Occipital Bone''' ===
===='''Membrana Tectoria'''====
The Membrana Tectoria. Two Alar. The Apical Odontoid.
''(occipitoaxial ligament)'' 
[[File:Gray308.png|thumb|Membrana tectoria (Gray 308)]]


==== '''The Membrana Tectoria''' ====
A broad, strong band within the [[vertebral canal]] and a superior continuation of the [[posterior longitudinal ligament]].  
'''(''occipitoaxial ligament'') (Figs. 307, 308)''' 
The membrana tectoria is situated within the vertebral canal. It is a broad, strong bands which covers the odontoid process and its ligaments, and appears to be a prolongation upward of the posterior longitudinal ligament of the vertebral column. 
It is fixed, below, to the posterior surface of the body of the axis, and, expanding as it ascends, is attached to the basilar groove of the occipital bone, in front of the foramen magnum, where it blends with the cranial dura mater. Its anterior surface is in relation with the transverse ligament of the atlas, and its posterior surface with the dura mater.


==== '''The Alar Ligaments''' ====
* Attached inferiorly to the posterior surface of the body of the [[axis]] 
'''(''ligamenta alaria; odontoid ligaments'') (Fig. 307)'''  
* Attached superiorly to the [[basilar part]] of the [[occipital bone]], anterior to the foramen magnum  
* Blends with the [[cranial dura mater]]


The alar [[ligaments]] are strong, rounded cords, which arise one on either side of the upper part of the odontoid process, and, passing obliquely upward and lateralward, are inserted into the rough depressions on the medial sides of the condyles of the occipital bone. In the triangular interval between these ligaments is another fibrous cord, the '''apical odontoid ligament''' (Fig. 308), which extends from the tip of the odontoid process to the anterior margin of the foramen magnum, being intimately blended with the deep portion of the anterior atlantoöccipital membrane and superior crus of the transverse ligament of the atlas. 
===='''Alar Ligaments'''====
''(ligamenta alaria; odontoid ligaments)'' 
[[File:Gray307.png|thumb|Alar ligaments (Gray 307)]]


It is regarded as a rudimentary intervertebral fibrocartilage, and in it traces of the notochord may persist. The alar ligaments limit rotation of the cranium and therefore receive the name of '''[[check ligaments]]'''  
Two strong, rounded cords arising on either side of the apex of the [[odontoid process]] and inserting into the medial sides of the occipital condyles. They limit rotation and are sometimes referred to as '''[[check ligaments]]'''.


In addition to the ligaments which unite the atlas and axis to the skull, the ligamentum nuchæ (page 290) must be regarded as one of the ligaments connecting the vertebral column with the cranium.
===='''Apical Ligament of the Dens'''====
''(ligamentum apicis dentis)'' 
A slender fibrous band extending from the tip of the odontoid process to the anterior margin of the [[foramen magnum]], blending with the [[deep anterior atlanto-occipital membrane]] and superior crus of the [[cruciate ligament of the atlas]]. It may contain remnants of the [[notochord]].


{{grays}}
===''Additional Connection: Ligamentum Nuchae'''===
__NOINDEX__
The [[ligamentum nuchae]] is a strong, midline structure that connects the [[spinous process]] of the [[seventh cervical vertebra]] and [[external occipital protuberance]]. It supports the head and functions as an additional ligament linking the vertebral column to the skull.
{{Bones of torso}}
{{Human regional anatomy}}
{{grays adapted}}
[[Category:Bones of the vertebral column]]
[[Category:Vertebrate anatomy]]
[[Category:Skeletal system]]
[[Category:Bones of the thorax]]
[[Category:Irregular bones]]
[[Category:Back anatomy]]
[[Category:Spine| ]]
[[Category:Craniovertebral joints]]

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Anatomy > Gray's Anatomy of the Human Body > III. Syndesmology > 5c. Articulations of the Vertebral Column with the Cranium

Henry Gray (1821–1865). Anatomy of the Human Body. 1918.

Articulations of the Vertebral Column with the Cranium[edit]

The ligaments connecting the vertebral column with the cranium are grouped into two sets:

  • Those uniting the atlas (C1 vertebra) with the occipital bone
  • Those connecting the axis (C2 vertebra) with the occipital bone

Articulation of the Atlas with the Occipital Bone (articulatio atlantoöccipitalis)[edit]

This joint consists of a pair of condyloid joints between the occipital condyles and the superior articular facets of the atlas.

Ligaments of the Atlanto-occipital Joint[edit]

Articular Capsules[edit]

(capsulæ articulares; capsular ligaments) Thin and loose capsules enclosing each atlanto-occipital joint, connecting the occipital condyles to the articular surfaces of the atlas.

Anterior Atlanto-occipital Membrane[edit]

(membrana atlantoöccipitalis anterior)

Anterior atlanto-occipital membrane (Gray 304)

A broad, dense fibrous membrane connecting the anterior margin of the foramen magnum to the anterior arch of the atlas. It is continuous laterally with the articular capsules and strengthened medially by a thick cord connecting the basilar part of the occipital bone to the anterior tubercle of the atlas.

Posterior Atlanto-occipital Membrane[edit]

(membrana atlantoöccipitalis posterior)

Posterior atlanto-occipital membrane (Gray 305)

A thin, broad membrane attached above to the posterior margin of the foramen magnum and below to the posterior arch of the atlas. Defective laterally to accommodate the vertebral artery and suboccipital nerve.

Lateral Atlanto-occipital Ligaments[edit]

These are thickened portions of the articular capsule reinforced by fibrous bands. They extend from the jugular processes of the occipital bone to the bases of the transverse processes of the atlas.

Synovial Membranes[edit]

Each atlanto-occipital joint contains a synovial membrane. Occasionally, they communicate with the synovial cavity behind the odontoid process of the axis.

Movements of the Atlanto-occipital Joint[edit]

The permitted movements include:

  • Flexion and Extension: e.g., nodding "yes"
  • Lateral Flexion: slight movement to one side
    • Muscles involved**:

Ligaments Connecting the Axis with the Occipital Bone[edit]

These include:

Membrana Tectoria[edit]

(occipitoaxial ligament)

Membrana tectoria (Gray 308)

A broad, strong band within the vertebral canal and a superior continuation of the posterior longitudinal ligament.

Alar Ligaments[edit]

(ligamenta alaria; odontoid ligaments)

Alar ligaments (Gray 307)

Two strong, rounded cords arising on either side of the apex of the odontoid process and inserting into the medial sides of the occipital condyles. They limit rotation and are sometimes referred to as check ligaments.

Apical Ligament of the Dens[edit]

(ligamentum apicis dentis) A slender fibrous band extending from the tip of the odontoid process to the anterior margin of the foramen magnum, blending with the deep anterior atlanto-occipital membrane and superior crus of the cruciate ligament of the atlas. It may contain remnants of the notochord.

Additional Connection: Ligamentum Nuchae'[edit]

The ligamentum nuchae is a strong, midline structure that connects the spinous process of the seventh cervical vertebra and external occipital protuberance. It supports the head and functions as an additional ligament linking the vertebral column to the skull.




Gray's Anatomy[edit]

Anatomy atlases (external)[edit]

[1] - Anatomy Atlases

Adapted from the Classic Grays Anatomy of the Human Body 1918 edition (public domain)