COMPARISON BETWEEN BIPOLAR PULSED RADIOFREQUENCY AND MONOPOLAR PULSED RADIOFREQUENCY IN CHRONIC LUMBOSACRAL RADICULAR PAIN
Authors: Chang MC, Cho YW, and Ahn SH
Study type: Prospective, Randomized controlled trial
Publication: Medicine (Baltimore) 2017; 96(9):e6236 (Link to PubMed)
Key Words: Lumbosacral Radicular Pain – Dorsal Root Ganglion – bipolar PRF vs monopolar PRF
Graph created by Boston Scientific based on the published data
To investigate the effect of bipolar Pulsed Radio Frequency (bPRF) stimulation of the DRG in patients with chronic lumbosacral radicular pain who were unresponsive to transforaminal epidural steroid injection (TFESI). The authors also compared the effect of bPRF to that of monopolar PRF (mPRF).
Patients: 50 patients with chronic lumbosacral radicular pain, refractory to TFESI, were recruited and randomly assigned to one of two groups; the bPRF (N=25) or mPRF (N=25).
- All patients had a longer than 6-months history of lumbar or sacral segmental pain radiating from the back toward the leg.
- Imaging findings confirmed either herniated lumbar disc or lumbosacral stenosis in the patients.
- Pain intensity was assessed by a blinded investigator using a numeric rating scale (NRS) at pre-treatment, and 1, 2, and 3 months after treatment. Successful treatment was defined as more than 50% reduction in NRS scores at 3 months follow-up.
PRF procedure: The affected DRG was punctured with one (mPRF) or two (bPRF) catheter needles (active tip electrodes) under fluoroscopy guidance. A sensory test was performed using an RF Generator (Cosman G4) until the patients reported a tingling sensation or dysesthesia, at less than 0.3V.
The PRF treatment was administered at 45V; 5ms PW; 5Hz for 360 seconds. The electrode tip did not exceed 42°C.
- NRS scores in both bPRF and mPRF groups showed a significant reduction at 1, 2, and 3 months after treatment, compared to baseline scores.
- NRS scores decline over time was significantly larger in the bPRF group, compared to mPRF group, at all follow-up time points.
- The rate of successful pain relief at 3-months posttreatment was significantly better for the bRFA group (76%) than for the mRFA (48%).
- The number of patients who used analgesics and calcium channel antagonists decreased dramatically for both treatment groups.
- The use of bPRF on the DRG can be an effective and safe interventional technique for chronic refractory lumbosacral radiculopathy.
- Bipolar PRF is a more effective method for managing chronic lumbosacral radicular pain compared to monopolar PRF.