Table 11

Guidelines for clinical trials vs clinical practice

FactorClinical trialClinical practice
Patient s election
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 t echnique
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 -r eported o utcomes
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 t echnique RFA t echnique
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.