Facet Joints in Spinal Pain

As a synovial joint, the z-joint may be affected by any of the inflammatory processes that involve joints, including rheumatoid arthritis

Facet Joint Arthritis

Figure 11.4. Axial computed tomography images depicting the anatomical variation in the articular surface of the facet joints. Joints may have straight or curved articular surfaces, and osteophytic ridging may make joint access difficult for intra-articular injections. (A) The L2-3 facet joints, which have a nearly straight contour in this patient, are oriented in a nearly sagittal plane. (B) The L5-S1 facet joints. In this patient, the articular processes have relatively convex and concave articular surfaces. Osteophytic ridging may make intra-articular access difficult without CT guidance.

Figure 11.4. Axial computed tomography images depicting the anatomical variation in the articular surface of the facet joints. Joints may have straight or curved articular surfaces, and osteophytic ridging may make joint access difficult for intra-articular injections. (A) The L2-3 facet joints, which have a nearly straight contour in this patient, are oriented in a nearly sagittal plane. (B) The L5-S1 facet joints. In this patient, the articular processes have relatively convex and concave articular surfaces. Osteophytic ridging may make intra-articular access difficult without CT guidance.

Figure 11.5. Posterior view diagram of the lumbar spine depicting the typical course of the "facet nerve" or medial branch dorsal ramus. In the lumbar spine, the nerve takes a very typical course along a groove at the junction of the superior articular process and transverse process of a vertebra. Note that each facet joint is supplied by smaller branches arising from the two adjacent medial branches. To block one facet joint, two medial branch injections are typically performed.

Facet Joint Injection Side Effects

and osteoarthritis. The fibrous, bony, and cartilaginous components of the joint may also be injured traumatically. Pain fibers (unmyelinated nerve endings) as well as substance P have been demonstrated in the synovial membrane within the joint and synovial membrane, and within the joint capsule as well. Pain innervation is also present in other local soft tissue structures adjacent to the joint including the multifidus,

Figure 11.6. Posterior view of the cervical spine depicting the course of the medial branch. In the cervical spine, the medial branch stereotypically courses along a small groove in the midportion of the lateral mass of a vertebra, before coursing along the bone to innervate the joint. As in the lumbar spine, each joint is supplied by medial branches from levels above and below the joint.

Figure 11.6. Posterior view of the cervical spine depicting the course of the medial branch. In the cervical spine, the medial branch stereotypically courses along a small groove in the midportion of the lateral mass of a vertebra, before coursing along the bone to innervate the joint. As in the lumbar spine, each joint is supplied by medial branches from levels above and below the joint.

Course Medial Branches

the local spinal nerves, and the dura and epidural space. Joint inflammation may cause localized hyperemia and venous stasis, thus affecting other local tissues. The exact neurological mechanisms of facet-mediated pain is incompletely understood, although demonstration of pain fibers in the joint and locally provide some possible explanation for what is now a relatively well-accepted pain syndrome (facet syndrome).6 Patients may also experience radicular symptoms as a consequence of irritation or mass effect on the spinal nerve locally.

The facet syndrome is characterized by one or more of the following typical complaints:

Local paraspinal tenderness over a facet joint

Posterior pain aggravated by extension and rotation toward the involved side

Hip and buttock pain in a nonradicular distribution Morning pain and stiffness

Occasional improvement with heat or anti-inflammatory drugs Positive response (pain relief) with joint injection

Images may demonstrate abnormalities in the joints including osteo-phytic spurring, accumulation of fluid in the joint capsule, or a localized synovial cyst. Bone scanning may demonstrate increased bony turnover locally, and examination by magnetic resonance imaging (MRI) may reveal enhancement locally about the joint. Often, however, there is a poor correlation between pain and imaging abnormalities, and the diagnosis is typically made on clinical grounds and confirmed by diagnostic facet joint block with elimination of pain.

Joint injections may be requested for either diagnostic or therapeutic indications.7-9 Diagnostic injection may be requested to confirm a clinical suspicion of a facet-mediated pain syndrome. The joint selected for injection may be specifically requested or determined from imaging studies or physical examination. Intra-articular injection of steroid may be used for longer acting anti-inflammatory activity, and there are reports of long-term effectiveness in pain management (>6 months pain relief) depending, of course, on the exact pathological process in the joint. Long-term pain relief appears to be most successful in treating posttraumatic facet syndrome, and injections may be useful to treat injuries of the whiplash and paraspinal strain types.

Facet Joint Block Technique

Facet joint blockade may be requested to confirm a suspected diagnosis of facet-mediated pain, to treat a symptomatic synovial cyst, as a precursor to possible medial branch neurotomy, or for management of chronic facet-mediated spinal pain.10-12 Contraindications are those typical for any injection procedure: specifically impaired coagulation, active infection, or allergy to the medications to be used. Levels to be injected are selected on the basis of specific request, physical symptoms (pain diagram), and imaging studies. It is often difficult to localize pain to a single level, and several joints (unilateral or bilateral) may be injected at the same setting, particularly for therapeutic purposes.

Multiple injections may confuse diagnosis, however, and should be avoided when a diagnosis block is requested. Injections may be performed with local anesthetic only for diagnosis, and steroid solution may be added if more long-lasting pain relief is the goal. Steroid injection remains somewhat controversial, and long-term benefits are as difficult to prove as they are to disprove. Intra-articular injection of steroid is a well-accepted therapy for pain in other joints (hips, knees, and shoulders), and there is anecdotal evidence of long-term pain relief from facet joint blocks with steroid. While long-term relief cannot be proven, steroid injection may prove useful, particularly in the setting of a comprehensive pain management program, which may include other adjuncts such as strengthening and stabilization therapy.

Injections are typically well tolerated and are performed under local anesthetic only, although some patients may request intravenous (IV) conscious sedation, especially if multiple levels are to be injected. A patient under conscious sedation should be rousable for questioning, since there sometimes is reproduction of typical pain (concordant provocative response) on injection into the joint, which may further substantiate the diagnosis. Injections are typically performed under fluoroscopic guidance, although computed tomography (CT) may be utilized for severely diseased or arthritic joints when intra-articular access is critical.

Several permissible techniques for facet joint blocks may be used and have been described in the literature, including intra-articular injec-tion,11-13 periarticular injection, and medial branch block.14,15 Intra-articular injection is imperative in some instances (specifically for attempt at drainage or treatment of symptomatic synovial cyst), although periarticular injections are most often used for chronic pain management. Medial branch blocks are most frequently requested as a diagnostic tool prior to planned medial branch rhizotomy (neurotomy), since some reports have suggested that medial branch block may be more accurate than direct joint injection for prediction of outcome.16-18

As with all spinal injections, the procedure, potential risks, and possible outcomes are discussed with the patient, and informed consent is obtained. Potential risks discussed with the patient should include allergic reaction, transient postprocedural pain flare-up, bleeding, and infection. If steroids are to be administered, side effects and risks associated with their use should be discussed as well, and if steroids must be used on a diabetic patient, he or she should be warned of transient effects on blood glucose levels.

For lumbar injections, the patient is placed in a prone position, and the back is cleansed and draped in the usual sterile fashion. The x-ray tube is obliqued to a position parallel to the joint (more obliquity is required in the lumbosacral junction and little obliquity at the thora-columbar junction). The orientation is selected under fluoroscopy to directly view the joint along the imaging plane, parallel to the articular surfaces of the articular processes (Figure 11.7). Once the joint has been profiled, local anesthesia is achieved in the skin overlying the joint along the selected plane of orientation. For intra-articular technique, a 22-gauge needle is advanced in the plane of the joint space until bone

Arthritis Relief Now

Arthritis Relief Now

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Responses

  • simon
    Is there increased pain with medial branch block when inflammation is present?
    4 years ago
  • peter loewe
    What is posterior osseous ridging?
    2 years ago

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