What movement occurs at the atlantoaxial joint?
The C1 C2 spinal motion segment, also called the atlantoaxial joint, is located in the upper portion of the cervical spine. It consists of the C1 and C2 vertebrae, and the anatomical structures connecting them. This segment provides rotational motion, supports the head, and protects the spinal cord and nerve pathways.
What happens at the atlanto-occipital joint?
Function. The movements permitted in this joint are: (a) flexion and extension around the mediolateral axis, which give rise to the ordinary forward and backward nodding of the head. (b) slight lateral motion, lateroflexion, to one or other side around the anteroposterior axis.
Is the atlanto-occipital joint a pivot joint?
The atlanto-occipital joint (O-C1) acts as a pivot for the flexion/extension motion of the cranium, with 13 degrees average flexion/extension and 8 degrees lateral bending, thus allowing only a few degrees of axial rotation.
Which joint is between atlas and axis?
pivot
The axis is the second cervical vertebra; it has what is called the odontoid process about which the atlas rotates. The joint between the atlas and axis is a pivot type of joint. It allows the head turn from side to side. It is also called the atloaxoid joint.
What joints have no movement?
Synarthroses (immovable). These are fixed or fibrous joints. They’re defined as two or more bones in close contact that have no movement. The bones of the skull are an example. The immovable joints between the plates of the skull are known as sutures.
Does the OA joint rotate?
The atlanto-occipital membrane connects the anterior portion of the foramen magnum to the anterior arch of C1 for anterior-posterior stability. The OA joint is responsible for 10 degrees of flexion, 25 degrees of extension, 5 degrees of sidebend, and 4 degrees of conjugate rotation.
What type of joint is C0-C1?
condyloid synovial joints
The atlanto-occipital articulation (also known as the C0-C1 joint/articulation) is comprised of a pair of condyloid synovial joints that connect the occipital bone (C0) to the first cervical vertebra (atlas/C1).
How does the atlantoaxial joint work?
The primary movement of the atlantoaxial joint complex is rotation. In rotation the atlas together with the head, rotate around the dens of axis. This movement allows us to turn our head to look towards the left or towards the right.
What is a condyloid joint example?
The condyloid joint occurs where an egg-shaped surface of a bone fits into a concavity in another bone. Examples include the wrist joint (radiocarpal joint) and the temporomandibular joint.
What kind of joint is the atlanto-occipital joint?
Atlanto-Occipital Joint. The right and left atlanto-occipital joints together form an ellipsoidal joint that allows movement in flexion, extension, and, to a lesser extent, left and right lateral flexion (Table 5-5). A little rotation also occurs between occiput and atlas (Standring et al., 2008).
Where does the atlanto-occipital articulation take place?
The atlanto-occipital articulation is comprised of a pair of condyloid synovial joints that connect the occiput (C0) to the first cervical vertebra (atlas/C1). Article:
Where does the rotation of the occipital joint occur?
Rotation (conjunct) Occurs with lateral flexion due to the slanted articular surfaces, anteromedial orientation of the articular facets, and the alar ligaments. Total ROM: 5-7° in each direction. Axis: Vertical axis anterior to the foramen magnum.
Is the atlanto-occipital joint locked in retroflexion?
In retroflexion the atlanto-occipital and atlantoaxial joints are locked and the examination looks at the region below C2/C3. The farther backward the cervical spine is inclined, the more the rotation takes place in the lower and cervicothoracic sections.