Atlantoaxial Joint Intraarticular Injection

Abstract

The atlantoaxial joints are the paired articulations between the inferior articulating processes of the atlas and the superior articulating processes of the axis. These joints are primarily responsible for the 0 to 45 degrees of lateral rotation in each direction of the cervical spine. These joints can become a source of axial cervical pain in the event of cervical trauma or as a result of degenerative joint disease. In the presence of atlantoaxial joint arthropathy, pain is usually exacerbated by cervical rotation. The distribution of axial cervical pain from atlantoaxial joint arthropathy usually involves the ipsilateral retromastoid, suboccipital, or posteroauricular region.

Keywords

Atlantoaxial, Cervical, fluoroscopy, headache, Injection, spondylosis

Note: Please see pages ii , iii for a list of anatomic terms/abbreviations used throughout this book.

The atlantoaxial (a0) joints are the paired articulations between the inferior articulating processes of the atlas and the superior articulating processes of the axis. These joints are primarily responsible for the 0 to 45 degrees of lateral rotation in each direction of the cervical spine. These joints can become a source of axial cervical pain in the event of cervical trauma or as a result of degenerative joint disease. In the presence of atlantoaxial joint arthropathy, pain is usually exacerbated by cervical rotation. The distribution of axial cervical pain from atlantoaxial joint arthropathy usually involves the ipsilateral retromastoid, suboccipital, or posteroauricular region.

Atlantoaxial joint injections are indicated for the diagnosis and management of upper cervical pain and headache that emanate from the atlantoaxial joints of the cervical spine. For patients with predominantly unilateral pain, the ipsilateral joint is injected. These joints can be injected with either a lateral or posterior approach. The posterior approach is widely considered to be a safer technique because fewer vital vascular and neural structures are encountered between the skin and joint line when using this trajectory.

In this chapter, a posterior approach is described for the injection of the lateral portion of the atlantoaxial joints. With this approach, the joint is accessed by using a trajectory view and advanced with the use of multiplanar imaging, with an emphasis on safety by using the lateral view to confirm the depth. Because the lateral view is used to assess the depth, one need not “step off” the inferior or superior articulation of the joint before penetrating the joint capsule, as is often recommended. With this approach, the trajectory view is an anteroposterior view with a slight caudad tilt (i.e., a pillar view); this also serves as one of the multiplanar views.

It is crucial to precisely target the lateral one third of the atlantoaxial (aa) joint because straying too far medially or laterally can have devastating consequences.

Trajectory View ( Fig. 31.1 )

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Place the patient in the prone position with the neck slightly flexed and the head supported.

Fig. 31.1

A, Fluoroscopic image of the trajectory view with the needle in position between the superior articular border (SAB) and inferior articular border (IAB). B, Radiopaque structures, anteroposterior (AP) trajectory view. (Dentition not drawn in.) C, Radiolucent structures, AP trajectory view. Figure 32.6 demonstrates an angiogram to visualize the course of the vertebral artery (VA) relative to the atlantoaxial (aa) and atlantooccipital (ao) joints and other relevant structures.
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Confirm the level (with the anteroposterior view).
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Tilt the fluoroscope’s image intensifier slightly cephalad or caudad to maximally view the targeted joint space silhouette and facilitate easier entry between the two joint articulations.
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Optimize the superior articular border (sab) and inferior articular border (iab) to the appropriate orientation.
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Stay at the junction of the lateral one third and the medial two thirds of the joint space.