The Atlanto-occipital joint (articulation between the atlas

Atlas (anatomy)

In anatomy, the atlas is the most superior cervical vertebra of the spine.It is named for the Atlas of Greek mythology, because it supports the globe of the head....

 and the occipital bone

Occipital bone

The occipital bone, a saucer-shaped membrane bone situated at the back and lower part of the cranium, is trapezoidal in shape and curved on itself...

) consists of a pair of condyloid joints. The atlanto-occipital joint is a synovial joint

Synovial joint

A Synovial joint, also known as a diarthrosis, is the most common and most movable type of joint in the body of a mammal. As with most other joints, synovial joints achieve movement at the point of contact of the articulating bones....

.

Ligaments

The ligaments connecting the bones are:

• Two Articular capsules
• Posterior atlantoöccipital membrane
  Posterior atlantoöccipital membrane
  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....
  
  
• Anterior atlantoöccipital membrane
  Anterior atlantoöccipital membrane
  The anterior atlantoöccipital 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....
  
  
• Lateral atlantoöccipital

Motions

The movements permitted in this joint are:

• (a) flexion
  Flexion
  In anatomy, flexion is a position that is made possible by the joint angle decreasing. The skeletal and muscular systems work together to move the joint into a "flexed" position. For example the elbow is flexed when the hand is brought closer to the shoulder...
  
   and extension
  Extension (kinesiology)
  In kinesiology, extension is a movement of a joint that results in increased angle between two bones or body surfaces at a joint. Extension usually results in straightening of the bones or body surfaces involved. For example, extension is produced by extending the flexed elbow. Straightening of...
  
   in the frontal axis, which give rise to the ordinary forward and backward nodding of the head.

• (b) slight lateral motion, lateroflexio, to one or other side in the sagital axis.

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

Semispinalis capitis

The Semispinalis capitis is situated at the upper and back part of the neck, deep to the Splenius, and medial to the Longissimus cervicis and 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.

Tension-like Headaches

The Atlanto-occipital joint features predominantly in the symptom of tension-like headaches as a result of prolonged inappropriate posture

Human position

Human positions refers to the different positions that the human body can take.There are several synonyms that refer to the human position, often used interchangeably, but having specific flavors....

 from poor ergonomic adaptation.

In such cases, patients typically report cracking of the neck, discomfort when sitting, continuous migraine

Migraine

Migraine is a chronic neurological disorder characterized by moderate to severe headaches, and nausea...

-like headaches, dullness, dizziness

Dizziness

Dizziness refers to an impairment in spatial perception and stability. The term is somewhat imprecise. It can be used to mean vertigo, presyncope, disequilibrium, or a non-specific feeling such as giddiness or foolishness....

, tingling in the fingers, sensitivity to light and a feeling the head is expanding.