The cervical zygapophyseal joints have been shown to be a potential source of pain from the cranium to the midthoracic spine (63). Cervical facet injections can provide diagnostic as well as therapeutic benefits for patients with a wide variety of head and neck pains.
After informed consent is obtained, the patient is placed in the prone position with the neck flexed and head turned to the opposite side to open the facet joint. A cushion is placed under the chest to allow neck flexion. The skin entry site lies about two vertebral segments below the target joint. The patient is prepared in a standard aseptic fashion over an area large enough to allow palpation of landmarks, and sterile technique is used throughout the procedure. A 3-in. (8-cm), 22-gauge spinal needle is advanced superiorly to the inferior margin of the joint. While advancing at a 45-degree angle, care is taken to ensure the needle is directed over the articular pillars and not allowed to stray medially toward the interlaminar space or excessively laterally. The needle is advanced until contact is made with the articular pillar, either above or below the targeted joint, and then redirected into the joint capsule. Lateral and anteroposterior fluoroscopic views are necessary to ensure that the needle is advanced to the joint midpoint. Injection of contrast media can be used to confirm proper placement in the joint. After negative aspiration, the joint is injected with a 1-mL or less mixture of 6 mg mixture of betamethasone sodium phosphate and betamethasone acetate and local anesthetic (Fig. 67-34). Excessive injectate volume may spread to the epidural space via communication with the joint.
FIGURE 67-34. Cervical zygapophyseal joint injection. Fluoroscopic approach for injection (arrows).
Total injected volume should not exceed 1 mL, because the joint volume is usually 1 mL or less. Anterior needle placement should be avoided because the neural foramen, epidural space, and vertebral artery are in close proximity to the anterior surface of the cervical joint.
Serious complications from cervical zygapophyseal joint injections are uncommon when meticulous care is given to ensure proper needle placement before injection. Local postinjection pain and light-headedness may occur. Ataxia and dizziness may occur if local anesthetics are used at the more proximal segments, secondary to loss of postural tonic-neck reflexes and proprioceptive input to the cervical muscles. The type of local anesthetic used will determine the duration of these effects. Vertebral artery injection of even small amounts of local anesthetic can cause a seizure; stroke is also possible if particulate steroids are used. Epidural or spinal blockade can occur if the needle placement is medial, resulting in regional blockade, respiratory compromise, and hypotension.