Guidelines for clinical trials vs clinical practice
| Factor | Clinical trial | Clinical practice |
| Patient selection | ||
| Failure of conservative treatment | At least 3 months | Preferably 3 months, but may be less in certain circumstances (eg, incapacitating pain with strong suspicion of facetogenic origin, competitive athlete, military deployment) |
| Physical examination | No recommendation | No recommendation |
| Diagnostic imaging | No recommendation | No recommendation |
| Facet block technique | ||
| Injectate volume: | ||
| Medial branch block | ≤0.5 mL | ≤0.5 mL |
| Intra-articular block | <1.5 mL | <1.5 mL |
| Imaging: | ||
| Medial branch block | Fluoroscopy | Fluoroscopy |
| Intra-articular block | CT | Fluoroscopy or CT |
| Contrast | 0.1–0.3 mL | With or without contrast |
| Sedation | None | Not 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 blocks | Strongly consider for efficacy studies | Not routinely |
| Repeat diagnostic MBB for repeat RFA | No | No |
| RFA techniqueRFA technique | ||
| Stimulation | Motor necessary; sensory recommended in the absence of multiple lesions | Motor strongly recommended; sensory at discretion of practitioner |
| Needle size | Large (preferably at least 18-gauge) | Large |
| Temperature | 80°C–90°C | 80°C–90°C |
| Duration | Preferably at least 2 min | At least 1.5 min |
| Multiple lesions and/ or other techniques to increase lesion size | Necessary in the absence of clear-cut stimulation benchmarks | Depends on circumstances |
MBB, medial branch block; RFA, radiofrequency ablation.