The Effect of Sensory Stimulation Threshold on the Efficacy of Pulsed Radiofrequency Applied to the Dorsal Root Ganglion in Patients with Chronic Lumbar Radicular Pain

"Using C-arm fluoroscopy, a 22G, 10 cm RF needle with a 5 mm active tip will be directed from lateral to medial towards the vertebral foramen. Once the needle reaches the lateral edge of the pedicle shadow, the C-arm will be adjusted to a lateral view to confirm that the needle is located at the craniodorsal portion of the intervertebral foramen. Sensory stimulation will be delivered through the RF generator at 50 Hz, and paresthesia will be sought in the corresponding dermatome at values between 0.4-0.8 mA.~After achieving paresthesia, motor stimulation at 2 Hz will be applied, and the location near the DRG will be confirmed if motor stimulation is not elicited at values less than 1.5 times the sensory threshold. Pulsed RF will then be applied for 4 minutes at a setting of 45 V, 20 ms pulse width, and 2 Hz frequency. Following the application, needle will be directed slightly anterior and after appropriate contrast flow, dexamethasone will be injected."