Effectiveness of Facet Joint Nerve Blocks in Managing Chronic Axial Spinal Pain of Facet Joint Origin: A Systematic Review and Meta-Analysis.

Background: Chronic axial spinal pain is one of the major causes of disability. Literature shows that spending on low back and neck pain and musculoskeletal disorders continues to escalate, not only with disability, but also with increasing costs, accounting for the highest amount of various disease categories. Based on the current literature utilizing controlled diagnostic blocks, facet joints, nerve root dura, and sacroiliac joints have been shown as potential sources of spinal pain. Therapeutic facet joint interventional modalities of axial spinal pain include radiofrequency neurotomy, therapeutic facet joint nerve blocks, and therapeutic intraarticular injections.

Objective: The objective of this systematic review and meta-analysis is to evaluate the effectiveness of facet joint nerve blocks as a therapeutic modality in managing chronic axial spinal pain of facet joint origin.

Study design: A systematic review and meta-analysis of randomized controlled trials (RCTs) and observational studies utilizing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist.

Methods: The available literature on facet joint nerve blocks in axial spinal pain was reviewed. The quality assessment criteria utilized were the Cochrane review criteria to assess risk of bias, the Interventional Pain Management Techniques - Quality Appraisal of Reliability and Risk of Bias Assessment (IPM-QRB) for randomized therapeutic trials, and the Interventional Pain Management Techniques - Quality Appraisal of Reliability and Risk of Bias Assessment for Nonrandomized Studies (IPM-QRBNR) for nonrandomized studies. The evidence was graded according to Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) assessment criteria. The level of evidence was based on best evidence synthesis with modified grading of qualitative evidence from Level I to Level V. A comprehensive literature search of multiple databases from 1966 to July 2023, including manual searches of the bibliography of known review articles was performed. Quality assessment of the included studies and best evidence synthesis were incorporated into qualitative and quantitative evidence synthesis.

Outcome measures: The primary outcome measure was the proportion of patients with significant relief and functional improvement of greater than 50% of at least 3 months. Duration of relief was categorized as short-term (less than 6 months) and long-term (greater than 6 months).

Results: This assessment identified 8 high-quality and one moderate quality RCTs and 8 high quality and 4 moderate quality non-randomized studies with application of spinal facet joint nerve blocks as therapeutic modalities. However, based on the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) assessment, only 3 of the 21 studies showed high levels of evidence and clinical applicability, with 11 studies showing moderate levels of GRADE evidence and clinical applicability.

Limitations: Despite the availability of multiple studies, the paucity of literature is considered as the major drawback. Based on Grading of Recommendations, Assessment Development, and Evaluations (GRADE) assessment, only 3 of the 21 studies showed high levels of evidence and clinical applicability.

Conclusion: Based on the present systematic review and meta-analysis with 9 RCTs and 12 non-randomized studies, the evidence is Level II with moderate to strong recommendation for therapeutic facet joint nerve blocks in managing spinal facet joint pain.