Introduction
Interventional procedures are frequently used to manage chronic spine pain (CSP) despite controversy concerning their effectiveness. We conducted a systematic review and network meta-analysis to establish the comparative effectiveness of frequently used procedures for chronic, axial or radicular, spine-related pain.
Method
We searched MEDLINE, EMBASE, CINAHL, CENTRAL, and Web of Science databases up to 24 January 2023, and included randomised controlled trials comparing different interventional procedures used to treat patients with CSP, or an interventional procedure vs. sham or usual care, and captured outcomes at ≥1 month follow-up. We excluded studies on chronic spine pain associated with cancer, infection, fracture or inflammatory rheumatic disease.
We collected data on pain relief at the follow-up time closest to, but not exceeding, 3-months for injections and the timepoint closest to, but not exceeding, 6-months for nerve ablation procedures. We conducted frequentist network meta-analyses to summarise the evidence and used the GRADE approach to rate the certainty of evidence.
Results
A total of 81 trials with 7,977 patients that explored 15 procedures were included in meta-analyses. All subsequent effects refer to comparisons with sham procedures and are provided as the weighted mean difference [WMD] on a 10cm VAS for pain; the minimally important difference is 1.5cm.
For axial spine pain, moderate certainty evidence shows that epidural injection of local anesthetic (WMD 0.28 [95% CI -1.18 to 1.75]), epidural injection of local anesthetic and steroids (WMD 0.20 [95% CI -1.11 to 1.51]), radiofrequency of the dorsal root ganglion (WMD 0.50 [95% CI -1.31 to 2.31), and joint-targeted steroid injection (WMD 0.83 [95% CI -0.26 to 1.93]) result in little to no difference in pain relief. Low certainty evidence suggests that intramuscular injection of local anesthetic (WMD -0.53 [95% CI -1.97 to 0.92]), epidural steroid injection (WMD 0.39 [95% CI -0.94 to 1.71]), joint-targeted injection of local anesthetic (WMD 0.63 [95% CI -0.57 to 1.83]), and joint-targeted injection of local anesthetic with steroids (WMD 0.22 [95% CI -0.42 to 0.87]) may provide little to no difference in pain relief; intramuscular injection of local anesthetic with steroids may increase pain (WMD 1.82 [95% CI -0.29 to 3.93]). Effects for joint radiofrequency ablation were supported by only very low certainty evidence.
For radicular pain, moderate certainty evidence shows that epidural injection of local anesthetic and steroids (WMD -0.49 [95% CI -1.54 to 0.55]) and radiofrequency of the dorsal root ganglion (WMD 0.15 [95% CI -0.98 to 1.28]) results in little to no difference in pain relief. Low certainty evidence suggests that epidural injection of local anesthetic (WMD -0.26 [95% CI -1.37 to 0.84]) or epidural injection of steroids (WMD -0.56 [95% CI -1.30 to 0.17]) results in little to no difference in pain relief. Effects for joint radiofrequency ablation and joint-targeted injection of steroids were supported by only very low certainty evidence.
Discussion
All interventional procedures supported by low to moderate certainty evidence showed no evidence of improved pain relief, compared to sham procedures, for axial or radicular chronic spine pain.