Cervical and thoracic zygapophyseal joint arthropathy refers to degenerative changes in the zygapophyseal joints (facet joints, z-joints) of the spine which may result in facet-mediated head, neck, and back pain.
It results from osteoarthritis of the z-joints, and it is a component of spondylosis, spondylolisthesis, trauma, and whiplash. Z-joints are considered part of the third, or posterior column of the spine, and usually deteriorate after the first, or anterior column, involving the intervertebral disks. The facet joints are often referred to as part of the “posterior elements”.
Epidemiology including risk factors and primary prevention
In patients with localized cervical or thoracic pain, the prevalence of z-joint pain amounts to 36-67% and 34-48%, respectively. This is in comparison to lumbar facet-mediated pain, which only accounts for 16-41% of lower back pain.1 The prevalence increases to 50-60% in trauma-induced chronic pain, including whiplash.2 In addition, 70% of cervicogenic headaches, which are seen in 4.1% of the population, result from C2-C3 z-joint arthropathy.3 Peak prevalence is in middle-aged individuals. Risk factors include genetics, major depression, and sedentary occupations that involve repetitive precision work with high level of muscular tension, such as data entry/management jobs.1,4Primary prevention is directed at modification and reduction of risk factors. There are no studies to date addressing race, sex, or morbidity/mortality of facet-joint mediated pain.
Z-joints are diarthrodial joints formed by the superior articular process of one vertebrae and the inferior articular process of the vertebrae above. In the cervical spine, they are oriented in a coronal oblique plane; in the thoracic spine, they are in a coronal plane. The z-joints function to limit excessive flexion, extension, side-bending, and axial rotation. The C2-3 z-joint is innervated by the third occipital nerve and a separate articular branch of the posterior ramus of C3. The C3 medial branch nerve innervates the C3-4 z-joint. The remainder of the joints have a bisegmental innervation from the medial branch of the dorsal rami of the same level and the level above it.5
Disease progression including natural history, disease phases or stages, disease trajectory (clinical features and presentation over time)
The intervertebral disc and the z-joints are the only articulations between adjacent vertebrae. They serve to stabilize and restrict excessive motion in the spine. Z-joint arthropathy is commonly seen in patients with degenerative disc disease and typically develops subsequent to it.6Degenerative z-joint changes are similar to those seen in other joints: osteophyte formation, articular process hypertrophy, osteosclerosis, thinning of articular cartilage with subchondral cyst formation, vacuum joint phenomenon or joint effusion, and hypertrophy of the joint capsule and ligamentum flavum.7 Joint hypertrophy causes distortion of the articular surfaces which can cause axial and/or referred pain.8
Specific secondary or associated conditions and complications
Complications include lateral recess stenosis, which may cause radicular symptoms. Z-joint arthropathy and associated ligamentum flavum hypertrophy can lead to central canal stenosis and subsequently result in myelopathy.7 Synovial cysts, while more common in the lumbar spine, can form in the cervical/thoracic joint, and may result in radicular symptoms.9 In rare instances, severe z-joint arthropathy can lead to segmental instability and joint subluxation. Whiplash injuries can result in chronic neck pain and headaches; frequently this pain is referred from z-joints, especially C2-3, injury.3
2. ESSENTIALS OF ASSESSMENT
There are no symptoms specific/unique to facet-mediated neck/back pain. Patients may present with non-specific symptoms which include deep/achy pain localized to paravertebral region (unilateral or bilateral) that may be exaggerated by hyperextension, twisting, side bending and torsional loads. Rarely is the pain axial or central. Patients may also report headaches or morning neck stiffness. Facet arthropathy pain is largely progressive, except when caused by trauma or whiplash injuries.10
Patients may present with specific referral patterns to the occiput, neck and upper back which may correlate to specific facet joints. Published sclerotomal pain maps identify these common referral areas, however they are very non-specific in terms of pathology and are substantially variable in spinal level overlap.11 These findings should be interpreted with caution as other pathologies such as discogenic pain can produce similar pain patterns.12
Facet-mediated neck/back pain is largely a diagnosis of exclusion. There are no specific signs or special examination maneuvers/movements to aide in the diagnosis. Diagnosis is often guided by the absence signs that may suggest alternate etiologies, such as neurological impairment or radicular symptoms.4 Numerous quality studies consistently fail to demonstrate a correlation between the popularized “facet loading” maneuver (pain upon extension and ipsilateral rotation) and facet mediated pain.10 The only physical exam finding that appears to consistently correlate with facet arthropathy, and later successful treatment, is paraspinal tenderness, which has been shown to distinguish facet pain from discogeninc back pain.10 Manual spine examination, when used in conjecture with paraspinal tenderness, may also be a useful clinical tool.13 Additional examination findings may include: range of motion restrictions (specifically in flexion, extension, and rotation), cervical kyphosis (loss of normal lordotic curvature), and hypertonicity of anterior/middle scalenes, trapezius, and sternocleidomastoid.
Patients may assume a forward flexed kyphotic posture to alleviate pain and will likely have limited mobility in all planes.11 Pain may be exacerbated by going from a sitting to standing position.14 Upper cervical spine z-joint arthropathy can limit head rotation, causing difficulty with driving, and can hinder conversations in social situations. These impairments may lead to decreased quality of life and can contribute to depression, especially in elderly patients.
Laboratory studies are indicated if there is suspicion of underlying cancer, rheumatologic disease, inflammatory disease, and infectious process, as well as in cases of unexplained spinal pain. In appropriate patients, Human Leukocyte Antigen-B27, Antinuclear Antibody, Rheumatoid Factor, and Serum Protein Electrophoresis are indicated.
The primary role of imaging is to exclude other pathologies (i.e., disc disease, tumor, fracture). X-ray, magnetic resonance imaging (MRI), computerized tomography (CT), and bone scan can reveal z-joint arthropathy, even in its early stages.14 Degenerative changes seen on imaging, however, lack predictive value for corresponding z-joint mediated pain, as degenerative changes are often seen in asymptomatic patients.15 Imaging may help to exclude z-joint arthropathy, as multiple radiological studies have demonstrated that disc degeneration almost always precedes z-joint degeneration, especially in older adults.10
Supplemental assessment tools
In addition to the clinical reference standard, the gold standard for diagnosis utilizes diagnostic medial branch blocks (MBB).5,16 Using fluoroscopic guidance, anesthetic medication can be injected adjacent to the medial branch nerves to assess for pain reduction. Clinically, a reduction in pain of 50% is considered a successful block; however, an 80% pain reduction it typically used in studies.17 Pain reduction following nerve block is not only diagnostic, it correlates with prognosis and response to further treatments. To minimize false positives, which can be as high as 58% in the thoracic spine and 27-63% in the cervical spine, a second diagnostic block is recommended with a different anesthetic (i.e., lidocaine vs. marcaine) in order to evaluate if pain relief is reproduced.10Compared to single blocks, the use of double blocks is associated with higher radiofrequency ablation (RFA) success rates, but with lower overall success rates, which is attributed to the increased rate of false-negative diagnostic blocks and elimination of placebo responders.10 MBBs may not be efficacious in patients with aberrant innervation of z-joints and when branches of the primary posterior ramus innervate other pain–generating structures (i.e. back muscles).
Early predictions of outcomes
Local pressure pain, defined as pain when applying pressure of at least 4 kg, is a predictor of RFA success.17 Ninety percent of patients who have successful pain relief with initial RFA have been shown to report satisfactory pain relief for eight to twelve months with subsequent RFAs.18
Patients with obesity and scoliosis are at higher risk for osteoarthritis.15Sedentary jobs at computer desk stations and those involving repetitive precision work with high level of muscular tension can be occupational risks.
Social role and social support system
Chronic neck pain can contribute to missed work and disability. Biopsychosocial variables such as self-esteem, coping mechanisms, home and community support network, and workplace satisfaction come into play. Cognitive behavioral therapy shows improvement in somatic, behavioral, and cognitive symptoms but only a small effect on pain.4 Lack of social support in the work environment also appears to have an effect.19 In contrast to patients with low back pain, psychological factors such as avoidance behavior and catastrophizing are not related to neck pain.5
Z-joint mediated pain can be mimicked by malingerers and patients with secondary gain, given that it is a diagnosis of exclusion with no absolute findings.
3. REHABILITATION MANAGEMENT AND TREATMENTS
Available or current treatment guidelines
Conservative treatment is recommended initially for both acute and chronic z-joint pain. Exercise therapy, including physical therapy, has the strongest evidence for efficacy compared to all other non-interventional treatments.10 Physical therapy has been shown to have a better outcome than a home exercise program, and is the best choice when choosing conservative treatment.19 Treatment focus is on posture correction, range of motion, muscular strengthening, and activity modification. Acupuncture, manipulation, and mobilization via chiropractic treatment and osteopathic manipulation has a positive short-term effect on pain relief,20 but when compared to sham, other non-interventional treatments, or physical exercise, the results are inconclusive.10
Medications such as NSAIDs are beneficial for neck and back pain, but have associated adverse effects, especially in in elderly patients. Topical agents are employed at all stages of the disease with variable results. A multidisciplinary approach should be employed, with minimally invasive interventional techniques offered to patients not responding to conservative treatment. RFA of the medial branch can be considered after a successful diagnostic anesthetic MBB(s). MBBs are the preferred interventional treatment technique over intra-articular z-joint injections. Comparatively, intra-articular injections, diagnostic (with local anesthetic) or therapeutic (with steroids), are more difficult to preform, are inferior diagnostic and prognostic indicators of RFA, and studies suggest that cervical spine intra-articular z-joint corticosteroid injections are largely ineffective.10 Alternative treatments such as hyaluronic acid injections into non-lumbar z-joints have not been studied.10 There is a lack of evidence for arthrodesis and surgery for spondylosis or facet-mediated pain. Surgery can, however, be indicated in patients with symptomatic instability of the spine.
At different disease stages
- Initial management is focused on medical and rehabilitation treatment. This includes NSAIDs, topical agents, ice/heat, physical therapy, chiropractic interventions, and home exercise. The primary goal is risk factor modification, postural training, activity modification, and mobilization. Early z-joint injections are sometimes performed for very painful presentations and may aid in participation in therapy.14 Muscle relaxants, including cyclobenzaprine, are effective agents for acute neck and back pain.10 Lastly, opioids provide short-term (less than 3 months) pain relief, but there is weak and inconsistent evidence for long-term use.
- If symptoms have been present for more than three months and have not responded to conservative treatment, interventional methods are often indicated, as detailed above. These interventions include intra-articular corticosteroid injections (though evidence supporting their efficacy remains weak) and RFA following diagnostic MBB. The addition of corticosteroid to local anesthetic has not been shown to provide a better outcome and is not recommended as first-line interventional therapy.21
- Currently, RFA is the standard of care for facetogenic pain. Analysis shows that initial cervical spine RFA provides pain relief for an average of 7 to 9 months, and up to a year in some patients, in approximately 60% of patients.10 Pain relief greater than 3 months is an indication for repeating RFA.).18,22 RFA typically is more efficacious for cervical compared to lumbar facets, largely because cervical nerve anatomy patterns facilitate better electrode placement and subsequent RFA success.10 Thoracic RFA is comparatively more difficult due to anatomic innervation variants and more complicated electrode placement. There are no comparative studies between IA injections and RFA.23 The focus from a functional perspective is still on restoring range of motion and strengthening postural muscles.
- In the chronic phase, if RFA has yielded positive results it can be repeated every six months. On subsequent RFA, more than 90% of patients reported satisfactory pain relief with 8-12 months of pain relief.18,22 Therapeutic intra-articular z-joint injections, while less commonly used due to poor efficacy, can be performed 4-6 times per year. If a patient has failed conservative and interventional management, their treatment becomes quite difficult. Transcutaneous electrical nerve stimulation (TENS) units may be considered as an alternate treatment modality.
The three main reasons for treatment failures are misdiagnosis, poor selection of patients for treatment, and technical failures. Depression, opioid use, radiation of pain to the occiput, previous back surgery, and a greater number of affected vertebral levels were associated with treatment failure of spinal facet pain. In addition, RFA of the C2-C3 level is also associated with a lower success rate compared to RFA of lower levels.10 Psychiatric comorbidity appears to be a risk factor for diminished pain relief after a MMB injection.1
Coordination of care
The physiatrist’s role is to coordinate a multidisciplinary approach to treatment. This includes physical therapy and home exercise programs, environmental modifications, nutrition, medications, manipulation, interventional techniques and addressing psychological factors.
Patient & family education
Patient and family education should be focused on risk factor reduction and modification, including smoking cessation, weight loss, postural mechanics, ergonomic adjustment, and home exercise programs.
Patients’ response to treatment can be measured by the visual analog scale or numerical rating scale, and the McGill Pain Questionnaire, Neck Disability Index, and Pain Disability Questionnaire. The use of ultrasound is currently under investigation for cervical MBBs. While promising, studies are limited.24
Translation into practice: practice “pearls”/performance improvement in practice (PIPs)/changes in clinical practice behaviors and skills
Conservative measures, such as medications and therapy followed by local joint injections are the mainstay of treatment. If symptoms progress beyond three months, interventional diagnostic methods such as MBB can be employed. If these blocks are successful, RFA can provide longer-lasting pain relief.
4. CUTTING EDGE/EMERGING AND UNIQUE CONCEPTS AND PRACTICE
Cutting edge concepts and practice
Pulsed, rather than continuous, RFA consists of smaller amounts of current at a lower temperature compared to thermal ablation. This is considered a safer alternative, although the risks are minimal when thermal ablation is performed correctly. Cooled RFA in the thoracic spine is a promising technique, and allows treatment of large lesions that compensate for the anatomic variability in the region.25 With proper technique and fluoroscopic confirmation of needle placement, risks can be minimized.
5. GAPS IN THE EVIDENCE-BASED KNOWLEDGE
Gaps in the evidence-based knowledge
There is limited research regarding the efficacy of conservative treatments such as physical therapy, manipulation, chiropractic adjustment, traction units, and acupuncture. The lack of a true placebo for nerve blocks has limited researchers’ ability to perform placebo-controlled trials, thereby restricting the concrete evidence needed for verifying the diagnostic accuracy and treatment efficacy of this procedure.1 Evidence behind thoracic interventions is also limited because they are infrequently performed. Disagreement exists whether one versus two diagnostic MBBs are considered sufficient as one MBB alone cannot control for false positives.1 In addition, there are no studies comparing MBBs to intra-articular blocks/injections at the cervical or thoracic facet levels, mostly due to the high risk associated with intra-articular injections at these levels. Further research is needed to establish evidence-based guidelines regarding the diagnosis and treatment of z-joint arthropathy and appropriate indications for interventions.
- Boswell MV, Manchikanti L, Kaye AD, et al. A Best-Evidence Systematic Appraisal of the Diagnostic Accuracy and Utility of Facet (Zygapophysial) Joint Injections in Chronic Spinal Pain. Pain Physician. 2015;18:E497-533.
- Gellhorn AC. Cervical facet-mediated pain. Phys. Med. Rehabil. Clin. N. Am. 2011;22:447–458.
- Mehnert MJ, Freedman MK. Update on the Role of Z-Joint Injection and Radiofrequency Neurotomy for Cervicogenic Headache. PM R. 2013 Mar;5:221-7.
- van Eerd M, Patijn J, Lataster A, et al. 5. Cervical facet pain. Pain Pract. Mar-Apr 2010;10(2):113-123.
- Bogduk N, McGuirk B. Acute neck pain: natural history. In: Bogduk N, McGuirk B, eds. Management of Acute and Chronic Neck Pain: An Evidence-based Approach. Philadelphia, PA: Elsevier; 2006:31-34.
- Butler D, Trafimow JH, Andersson GB, McNeill TW, Huckman MS. Discs degenerate before facets. Spine (Phila Pa 1976). Feb 1990;15(2):111-113.
- van den Hauwe L. Pathology of the Posterior Elements. In: van Goethem J, van den Hauwe L, Parizel P, eds. Spinal Imaging: Diagnostic Imaging of the Spine and Spinal Cord. New York, NY: Springer; 2007:157-172.
- Carrera GF. Lumbar facet joint injection in low back pain and sciatica: preliminary results. Radiology. Dec 1980;137(3):665-667.
- Stoodley MA, Jones NR, Scott G. Cervical and thoracic juxtafacet cysts causing neurologic deficits. Spine (Phila Pa 1976). Apr 15 2000;25(8):970-973.
- Cohen SP, Huang JH, Brummett C. Facet joint pain–advances in patient selection and treatment. Nat Rev Rheumatol. 2013;9:101–116.
- Aprill C, Dwyer A, Bogduk N. Cervical zygapophyseal joint pain patterns. II: A clinical evaluation. Spine (Phila Pa 1976). Jun 1990;15(6):458-461.
- Grubb SA, Kelly CK. Cervical discography: clinical implications from 12 years of experience. Spine (Phila Pa 1976). Jun 1 2000;25(11):1382-1389.
- Schneider GM, Jull G, Thomas K, Smith A, Emery C, Faris P, Cook C, Frizzell B, Salo P. Derivation of a clinical decision guide in the diagnosis of cervical facet joint pain. Arch Phys Med Rehabil. 2014;95:1695-701.
- Fenton D, Czervionke L. Facet Joint Injection and Medial Branch Block. In: Fenton D, Czervionke L, eds. Image-Guided Spine Intervention. Philadelphia, PA: Saunders; 2003:9-51.
- Friedenberg ZB, Miller WT. Degenerative Disc Disease Of The Cervical Spine. J Bone Joint Surg Am. Sep 1963;45:1171-1178.
- Manchikanti L, Boswell MV, Singh V, et al. Comprehensive evidence-based guidelines for interventional techniques in the management of chronic spinal pain. Pain Physician. Jul-Aug 2009;12(4):699-802.
- Cohen SP, Bajwa ZH, Kraemer JJ, et al. Factors predicting success and failure for cervical facet radiofrequency denervation: a multi-center analysis. Reg Anesth Pain Med. Nov-Dec 2007;32(6):495-503.
- Husted DS, Orton D, Schofferman J, Kine G. Effectiveness of repeated radiofrequency neurotomy for cervical facet joint pain. J Spinal Disord Tech. Aug 2008;21(6):406-408.
- Cote P, van der Velde G, Cassidy JD, et al. The burden and determinants of neck pain in workers: results of the Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associated Disorders. Spine (Phila Pa 1976). Feb 15 2008;33(4 Suppl):S60-74.
- Schellingerhout JM, Verhagen AP, Heymans MW, et al. Which subgroups of patients with non-specific neck pain are more likely to benefit from spinal manipulation therapy, physiotherapy, or usual care? Pain. Oct 31 2008;139(3):670-680.
- Manchikanti L, Singh V, Falco FJ, Cash KM, Fellows B. Cervical medial branch blocks for chronic cervical facet joint pain: a randomized, double-blind, controlled trial with one-year follow-up. Spine (Phila Pa 1976). Aug 1 2008;33(17):1813-1820.
- Smuck M, Crisostomo RA, Trivedi K, Agrawal D. Success of initial and repeated medial branch neurotomy for zygapophysial joint pain: a systematic review. PM R. 2012;4:686–692.
- Falco FJ, Erhart S, Wargo BW, et al. Systematic review of diagnostic utility and therapeutic effectiveness of cervical facet joint interventions. Pain Physician. Mar-Apr 2009;12(2):323-344.
- Obernauer J, Galiano K, Gruber H, Bale R, Obwegeser AA, Schatzer R, Loizides A. Ultrasound-guided versus Computed Tomography-controlled facet joint injections in the middle and lower cervical spine: a prospective randomized clinical trial. Med Ultrason. 2013;15:10-5.
- van Kleef M, Stolker RJ, Lataster A, Geurts J, Benzon HT, Mekhail N. 10. Thoracic pain. Pain Pract. Jul-Aug 2010;10(4):327-338.
Original Version of the Topic:
Thiru M. Annaswamy, MD, MA, Kinjal Parikh, DO. Cervical and Thoracic Zygapophsial joint arthropathy. Publication Date: 2012/12/28.
Clifford Everett, MD, MPH
Nothing to Disclose
Mark Bauernfeind, MD
Nothing to Disclose
David Essaff, DO
Nothing to Disclose