Table 11

Guidelines for clinical trials vs clinical practice

FactorClinical trialClinical practice
Patient selection
Failure of conservative treatmentAt least 3 monthsPreferably 3 months, but may be less in certain circumstances (eg, incapacitating pain with strong suspicion of facetogenic origin, competitive athlete, military deployment)
Physical examinationNo recommendationNo recommendation
Diagnostic imagingNo recommendationNo recommendation
Facet block technique
Injectate volume:
 Medial branch block≤0.5 mL≤0.5 mL
 Intra-articular block<1.5 mL<1.5 mL
 Medial branch blockFluoroscopyFluoroscopy
 Intra-articular blockCTFluoroscopy or CT
Contrast0.1–0.3 mLWith or without contrast
SedationNoneNot routinely
Patient-reported outcomes
Pain relief cut-off≥50%, consider subgroup analysis for higher thresholds in efficacy studies≥50%, with lower cut-offs considered in certain circumstances (eg, other metrics of improvement achieved)
Multiple blocksStrongly consider for efficacy studiesNot routinely
Repeat diagnostic MBB for repeat RFANoNo
RFA techniqueRFA technique
StimulationMotor necessary; sensory recommended in the absence of multiple lesionsMotor strongly recommended; sensory at discretion of practitioner
Needle sizeLarge (preferably at least 18-gauge)Large
DurationPreferably at least 2 minAt least 1.5 min
Multiple lesions and/ or other techniques to increase lesion sizeNecessary in the absence of clear-cut stimulation benchmarksDepends on circumstances
  • MBB, medial branch block; RFA, radiofrequency ablation.