Pulsed radiofrequency application in the treatment of chronic pain.

The efficacy of pulsed radiofrequency (PRF) in the treatment of painful lumbosacral spondylosis has been reported. This case series reviews 22 consecutive patients presenting to clinic who had been previously treated with PRF with good results. Patients being prescribed opioids were excluded. During the PRF application, tissue temperature was limited to 43 degrees C. A minimum of 200 mA of current was delivered in each case. The minimum current (at 50 Hz) necessary to stimulate the involved nerve was recorded. The duration of time from PRF treatment until the patient requested a subsequent application was documented. The effective duration of PRF in patients treated for lumbosacral spondylosis ranged from 5 to 18 months (mean +/- SD: 9 +/- 3.7 months; n = 16). PRF applications to dorsal root ganglia were effective from 2 to 12 months (7 +/- 3.8 months; n = 8). Similar results were observed when PRF was applied to cervical medial branch nerves, one suprascapular nerve, and one stellate ganglion. The mean (50 Hz) sensory stimulation thresholds obtained before treatment ranged from 0.08 V to 0.14 V. In this select population of patients not receiving controlled substances, who had a favorable response to a previous PRF application, the duration of pain relief supports the use of PRF as an effective pain treatment.