pulsed vs continuous radiofrequency neurotomy for cervical facet joint mediated pain

Conditions: Faceto-genic Neck Pain; Shoulder Pain Chronic; Faceto-genic Headache

Summary: different studies have revealed different success rates and patient satisfaction after cervical facet c-rf. in a study on 32 patients, with 15 months follow up, 25% had complete pain relief (8). another study had shown mean pain relief of 12.5 months and 11.5 months following a repeat procedure, with an effectiveness of 95% in 47 patients (8). in one study a success rate of 88% after first rf, and 86% following a repeat rf in 49 patients with facet mediated cervicogenic headache. they regarded the absence of anesthesia in the distribution of the 3rd occipital nerve, a technical failure (9). in a study from new zealand, demonstrated cervical facet rf as the sole treatment modality, produced 61% -74% complete pain relief with a median duration of 15-17 months in patients who had responded to facet joints diagnostic block (10). one more study in 2012 has demonstrated high voltage p-rf had a higher short-term effect compare to usual voltage, but results are still lower than c-rf (11). a double blind randomized prospective study has illustrated p-rf did not show any success rate in 6 months pain control, whereas c-rf had 95% pain control for trigeminal neuralgia (12). cohen in a recent study has compared p-rf with steroid injection for occipital neuralgia or migraine with occipital nerve tenderness (13). six weeks pain relief was 61% in p-rf group, and 36% in steroid injection group, with a positive outcome of 34%, and 26% respectively (13). one study on 2010 had reached to 52.6%, 6 months pain improvement on occipital neuralgia (14).

patients fulfilling eligibility criteria will be randomly allocated to prf or crf in a 1:1 ratio. the statistician will use redcap software to generate random numbers. patients will be registered to redcap software and will be concealed from both patients and health care staff. the study coordinator will enter patients' consent and study eligibility information to the redcap. once eligible, the redcap will assign the patient to one of the study group. patients will be blinded in the proposed study. the assessor is the person who will assess treatment success at the end of the study based on data from completed questionnaires. questionnaires will be completed every three months by patients through redcap system. a therapist is the person who will perform the procedure (pain specialist physician). the therapist will not be blinded, because of the nature of intervention. patient recruitment is estimated to be completed within 15-24 months. if the required sample size (calculated below) is recruited prior to this time, patient recruitment will be curtailed. during the first visit the investigator will perform eligibility for neck rf and patient will be received information about the study. patients will be book for two mbb 4-6 weeks apart. if the patient was eligible after the second mbb, patient will be asked to sign informed consent before screening. screening and recruitment, and randomization, and administer questionnaires will be performed by research co-ordinator. study informed consent form (icf) can be signed on the rf procedure day. if additional visits will be required to finalize the procedures related to the first visit they will be scheduled accordingly. after randomization the qualified participants will be scheduled for their rf. for the female subjects between the age of 18-50 a pregnancy test will be asked to obtain on screening visit in order to reduce the risk of pregnancy and potential harm to fetus, unless you had previous tubal ligation, or hysterectomy. post menopause patients are excluded. participants will be asked to complete the follow-up questionnaires at 1, 3, 6, 9, and 12 months. lanss questionnaire will be asked to be completed 6 weeks after rf. if the score was 12 or higher, patient will be asked to complete them every 4 weeks after till the score reduce to less than 12. lanss will be sent to the subjects through redcap software. on their last study visit, participants will have an exit interview, in addition to completing study measures.

Eligibility criteria:
inclusion criteria: age 18-90; pain duration \> 3 months cervical, shoulder pain or cevicogenic headache per pain diagram; two single blinded facet medial branch blocks (mbb) performed 30 days prior to the facet rf; subjects show 50% and more pain relief after each mbb (using vas for this assessment); unsuccessful or poorly tolerated previous treatments including: pain control medications, chiropractic, osteopathy, massage therapy, physiotherapy, acupuncture, aqua therapy, botox injection, and trigger point injection; exclusion criteria: non-english speakers; refusal to sign informed consent; less than 50% pain relief after mbb (using vas); variation in the dose of concomitant pain control medication less than 4 weeks before the procedure; allergy to medication or radiology contrast; patients with coagulation issues, those currently using anticoagulants and didn't stop them based on allevio clinic's policy for anticoagulants; pregnant patients; any pain interventions including previous rf, mbb, infusions 90 days prior to the first mbb for the same area (except failed botox injection, and trigger point injection);

Keywords: faceto-genic cervical pain chronic pain pulsed radiofrequency ablation continues radiofrequency ablation medial brunch block