atlantoaxial

The median atlantoaxial joint is sometimes considered a double joint:

The atlantoaxial ligament as the dorsal ramus emerges 3.

The lower border gives attachment to the posterior atlantoaxial ligament, which connects it with the axis.

The lateral atlantoaxial joint involves the lateral mass of atlas and axis.

In 11% of patients, there is atlantoaxial (upper neck vertebrae) instability that can lead to spinal cord compression, weakness and paralysis.

Atlantoaxial ligament can refer to:

Profound and complex neurological deficits may be found in patients with the combined deformity of atlantoaxial subluxation-subaxial subluxation-atlantoaxial impaction.

Any segment of the cervical spine may be affected by the rheumatoid inflammatory process, but destructive changes are most prominent at the occipito atlantoaxial junction.

Excessive laxity of the posterior transverse ligament can lead to atlantoaxial instability, a common complication in Down's Syndrome patients.

The atlantoaxial joint in common terminology is actually a composition of three: two lateral and one median atlantoaxial joints.

Atlantoaxial subluxation is the most common deformity and is due to destruction and resultant laxity of the transverse ligament.

Pathology of the C1-C2 (atlantoaxial) joint, the most mobile of all vertebral segments, accounts for 4% of all spondylosis.

No patient with atlantoaxial subluxation and fusion of C1 and C2 progressed to develop atlantoaxial impaction.

The bulging of this mass may further reduce the space available for the spinal cord and cause neurological deficits in patients with only a moderate degree of atlantoaxial subluxation.

Plain radiographs of the cervical spine in flexion and extension will allow recognition of atlantoaxial subluxation and subaxial subluxation.

Waldman S. et al., Atlanto-Occipital and Atlantoaxial Injections in the Treatment of Headache and Neck Pain.

This deformity has been termed cranial settling, superior migration of the odontoid, or atlantoaxial impaction and is seen almost exclusively in association with atlantoaxial subluxation.

Youhimoto H, et al., Kinematic Evaluation of Atlantoaxial Joint Instability: An In Vivo Cineradiographic Investigation.

Recent studies using magnetic resonance imaging in patients with atlantoaxial subluxation have shown an inflammatory mass of granulation tissue around the odontoid arising from the synovial lining of the articulations.

This periodontoid mass is not visible in patients who have had surgical fusion of the first two cervical vertebrae or in whom deformity has progressed to that of atlantoaxial impaction (see below).

The anterior atlantoaxial ligament is a strong membrane, fixed, above, to the lower border of the anterior arch of the atlas; below, to the front of the body of the axis.

The atlantoaxial articular capsules are thick and loose, and connect the margins of the lateral masses of the atlas with those of the posterior articular surfaces of the axis.

In patients with atlantoaxial impaction, however, odontoid erosion and osteoporosis may make plain radiographs inadequate for assessing the extent of cranial settling and resultant penetration of the odontoid into the foramen magnum.

The upper and lower borders respectively give attachment to the anterior atlantooccipital membrane and the anterior atlantoaxial ligament; the former connects it with the occipital bone above, and the latter with the axis below.

Extensive rheumatoid disease of the cervical spine results, then, in a combined deformity of atlantoaxial subluxation subaxial subluxation and atlantoaxial impaction - a devastating complication and a truly formidable therapeutic challenge.