Combined Continuous and Pulsed Radiofrequency Ablation for Pain Relief and Their Safety in Cervical Facet Pain
Condition: Radiofrequency Ablation
Study type: Interventional

Summary: 
      Continuous radiofrequency ablation (CRF) is the effective management for cervical facet joint
      pain but related with neuropathic symptoms in post-radiofrequency period. Additionally, pulse
      radiofrequency ablation (PRF) provides relief of neuropathic symptoms. However, the effect of
      CRF followed by PRF has yet to be validated
    

Detailed description: 
      Diagnostic procedure symptomatic facet joint was designated according to pain referral. Also,
      medial branches were injected with 2% lidocaine 0.3 ml per site.

      Treatment procedure The posterior technique was first described in 1995 . All interventions
      assessed the intravenous saline lock on arrival at the outpatient department using pulse
      oximetry and noninvasive blood pressure monitoring and intravenous sedation as required.
      Patients were assigned in a prone position under C-ARM fluoroscopic guidance with a
      Neurotherm NT 2000 Lesion Generator the (USA manufactured) . The electrode pad of the
      radiofrequency equipment was attached to the ipsilateral side of the posterior thigh. After
      the skin was then anesthetized with 1% lidocaine, a 20-gauge, 10-cm cannula with 10-mm curved
      active tip (Diros RF Cannula, Diros Technology Inc., Canada) was inserted along a 15 to 30
      degree angle to the sagittal plane (slightly posterior oblique approach) . The cannula was
      applied until reaching the lateral part of the articular pillar . Then the depth of the
      cannula was checked using a lateral view. A probe was inserted through the cannula and linked
      to a radiofrequency generator (Diros Technology OWL, Canada). After impedance were
      accomplished at below 500 Ohm, sensory stimulation was performed at 50 Hz and the patient
      reported not feeling any tingling sensation along the distribution of dermatome.
      Consequently, a motor stimulation (2 Hz) was executed until multifidus twitching was
      presented at stimulation less than 1 volts and no motor twitching was observed along the
      myotome. A non-ionic contrast medium was injected to ensure the intravascular injection
      before 1% lidocaine 0.5 ml was injected after the needle reached the desired location. The
      study investigated two lesions due to the anatomical variation of the medial branches.
      Patients in the CRF group (n = 16) underwent CRF at 80°C for 90 seconds for 2 cycles.
      Patients in the CPRF group underwent CRF at 80°C for 90 seconds for 1 cycle followed by PRF
      at 42°C for 120 seconds for 1 cycle. 0.125% bupivacaine plus 2 mg of dexamethasone in a total
      volume of 1 mL were injected after lesioning had performed.

      Measurement The demographic data including age, sex, comorbidities, body mass index (BMI),
      level of procedure, visual analog scale (VAS;1-100) Neck Pain Disability Index and
      complications were reviewed. It contains ten sectors: seven sectors related to everyday
      existing behaviors, two sectors correlated to pain, and one sector correlated to
      concentration. All items are marked from 0 to 5. A mark of 0 denotes the maximum level of
      function, while a mark of 5 indicates the bottom level of function. The maximum mark is 50,
      and a greater mark relates to an increased level of disability. The NDI scores were recorded
      before intervention and first month, third month, sixth month, ninth months and 12 months
      after intervention. The follow-up was performed either face to face or by phone, and patients
      were not permitted to use over-the counter analgesic medication. The primary outcome was
      number of patients who had successful treatment, expressed as at least 80% pain relief from
      baseline and NDI score less than 15 for at least 3 months . The secondary outcomes comprised
      the duration of pain relief defined as the time of pain relief until VAS had restored to at
      least 50% from baseline and side effects including numbness, ataxia, dysesthesia,
      hypersensitivity, itching and muscular weakness (dropped head syndrome) between group
      comparisons. A research assistant, who was uninvolved in the intervention or post-operative
      follow-up, collected all data in prospective medical records.
    

Intervention name(s): Flouroscopic guidance cervical medial branch radiofrequency ablation
Intervention type(s): Procedure
Intervention description(s): Electromagnetic wave deposition near nerve tissue for pain management
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: One model recieved continous RF while the other recieved combined pulsed and continous RF.
Masking: Double (Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: medial branch; Neck pain; Radiofrequency ablation