Table 11

Clinical studies evaluating AO joint injections

Author, yearPatient populationDesignResultsComments
Busch and Wilson, 198916825 pts with head and neck pain of which 2 pts received LA and steroid AO and AA joint injectionsRetrospectivePain relief in both cases ranged from 3 weeks to 4 months (1 patient received serial injections)No reported adverse events other than transient ataxia and worsening pain for 24–48 hours. Fluoroscopically-guided AO and AA injections performed concurrently
Dreyfuss et al 19941593 pts who received fluoroscopically-guided AO injectionsCase seriesPain relief in all 3 pts ranging from 6 to 12 monthsNo reported adverse events. Multiple concurrent injections limits generalization
Lee et al 201516529 pts with refractory headache and neck pain and findings suggestive of AO joint pain. Pts with ≥50% pain relief after diagnostic AO block underwent fluoroscopically-guided AO joint injections with LA and steroidProspective observational study20 of 24 (83%) pts had a positive diagnostic block. Pain scores and function improved from baseline at 2-month follow-upPts received two AO joint injections 1 week apart. No reported adverse events
Centeno et al 201815810 pts received bilateral AO joint injectionsCase seriesAll injections reported as ‘successful’ with no adverse eventsHead flexed to open up joint and rotated ipsilaterally to displace vertebral artery medially. Injectate composition not reported.
Effectiveness outcome measures and follow-up period not reported
Shin et al 201817123 pts with chronic upper cervical pain, pain score ≥3/10, and ≥50% pain relief after diagnostic AO joint block received either AO joint injection with LA and steroid (n=11) or pulsed RF of the AO joint (n=12)Randomized comparative-effectiveness trialPain score improved from baseline with sustained relief at 6 months with no differences between groupsBetween 60% and 70% of pts achieved >50% pain relief through 6-month follow-up. Study not blinded. No adverse events reported
El Abd et al 2008166Single patient with right-sided neck pain and headache due to congenital fusion of AO joints bilaterally. Two injections done with LA and steroidCase report2 weeks after second therapeutic injection, patient reported 75% improvement. At 6 and 12 month follow-ups, pain reduction persistedAuthors reported no noticeable improvement in ROM
  • AA, atlanto–axial; AO, atlanto–occipital; LA, local anesthetic; pts, patients; RF, radiofrequency; ROM, range of motion.