Atlanto-occipital joint

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Atlanto-occipital joint
Anterior atlantoöccipital membrane and atlantoaxial ligament.
Posterior atlantoöccipital membrane and atlantoaxial ligament.
Latin	articulatio atlantooccipitalis
Gray's	subject #74 295
MeSH	Atlanto-Occipital+Joint
Dorlands/Elsevier	a_64/12160970

The Atlanto-occipital joint (articulation between the atlas and the occipital bone) consists of a pair of condyloid joints.

The ligaments connecting the bones are:

• Two Articular capsules
• Posterior atlantoöccipital membrane
• Anterior atlantoöccipital membrane
• Lateral atlantoöccipital

The movements permitted in this joint are (a) flexion and extension, which give rise to the ordinary forward and backward nodding of the head, and (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.

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.

Major Joints

Vertebral column: atlanto-axial - atlanto-occipital - temporomandibular - sternocostal - sacroiliac Upper extremity: sternoclavicular - acromioclavicular - shoulder - elbow/proximal radioulnar articulation - wrist/distal radioulnar articulation - carpometacarpal - metacarpophalangeal - interphalangeal Lower extremity: hip - knee - ankle - subtalar - metatarsophalangeal