Table 22.

Guidelines for clinical trials versus clinical practice

Factor	Clinical trial	Clinical practice
Patient selection
History and physical examination of cervical facet joints	Inclusion criteria: Paraspinous muscle tenderness, ideally under fluoroscopy Pain with movement (eg, extension, rotation, lateral flexion) Pain consistent with referral maps Exclusion criteria: Radicular symptoms Bilateral neck pain unless study adequately powered Active psychological comorbidities	Inclusion criteria: Paraspinous muscle tenderness Pain with movement Pain consistent with referral maps Exclusion criteria: Radicular symptoms
History and physical examination AA/AO joints	No recommendation	No recommendation
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, deployment)
Radiological findings for facet joint pain	No recommendation	No recommendation
Patient reported outcomes	Follow IMMPACT and other relevant guidelines, more detailed than clinical practice	Dependent on patient’s goals
Pain relief cut-off for positive MBB	>50% (consider higher cut-off for efficacy trials or subgroup analysis)	>50%
Functional measures	Sole criterion not recommended for assessing MBB results (composite with pain relief should be considered for RFA effectiveness)	Sole criterion not recommended for assessing MBB results (composite with pain relief may be considered for RFA effectiveness)
Repeat RFA	>30% for at least 3 months per IMMPACT and lumbar facet guidelines29 281	>30% for at least 3 months per IMMPACT and lumbar facet guidelines29 281
Repeat diagnostic MBB for repeat RFA	No – previous RFA should be an exclusion criterion for studies not evaluating repeat RFA	No
Injection technique
AO and AA imaging	Pre-injection CT or MRI, fluoroscopy and real-time contrast injection with strong consideration of DSA or CT	Pre-injection CT or MRI, fluoroscopy and real-time contrast injection or DSA
Approach	Posterior/posterior oblique	Posterior/posterior oblique
Volume and prognostic test
Medial branch block	< 0.3 mL	< 0.3 mL
Diagnostic block (IA vs MBB)	MBB	MBB
Diagnostic block (single vs dual)	Single block (consider dual blocks only for efficacy studies)	Single block (consider dual blocks in individuals with low index of suspicion)
Imaging	Fluoroscopy or US	Fluoroscopy or US
Approach	Lateral (TON, C3–C7)	Lateral (TON, C3–C7)
	Posterior oblique (C8)	Posterior oblique (C8)
Volume and steroid use for AA/AO injections	Non-particulate <1 mL	Non-particulate <1 mL
Sedation	Avoid	Avoid
RFA technique
Stimulation	Motor for all levels	Motor for all levels
	Sensory for single lesions and C2–3	Sensory for single lesions and C2–3
Needle orientation	Parallel (preferable) or near-parallel	Parallel or near-parallel
	Posterior two-thirds of the articular pillar for C2–3	Posterior two-thirds of the articular pillar for C2–3
Lesion size	No recommendation due to unknown risk/benefit	No recommendation due to unknown risk/benefit
Cannulae confirmation	PA/lateral and possibly contralateral oblique	PA/lateral and contralateral oblique if necessary
Implanted devices	Exclude patients	Neurostimulators – deactivate
		Pacemakers – asynchronous mode if possible
		Defibrillators – deactivate if possible
Grounding pad placement	Dry, hairless skin devoid of tattoos	Dry, hairless skin devoid of tattoos
Spinal hardware	Exclude patients unless specifically addressing outcomes in this population	Avoid contact with hardware, adjust approach (eg, posterior oblique) as necessary
Repeat RFA	No more than twice/year	No more than twice/year
Post-lesion steroids	No steroids for efficacy study unless administered to all patients	Per physician judgment based on risk:benefit analysis
Anticoagulation	Exclude subjects who cannot stop anticoagulants	Discontinue only after careful risk:benefit assessment

AA, atlanto–axial; AO, atlanto–occipital; CT, computed tomography; DSA, digital subtraction angiography; IA, intra-articular; MBB, medial branch block; MRI, magnetic resonance imaging; PA, posteroanterior; RFA, radiofrequency ablation; TON, third occipital nerve; US, ultrasound.