The patient came to the clinic 23-April-2017 complaining of LBP for 1 week with bilateral sciatica more the left for 2 days with exacerbation last day of the sciatica with numbness both feet and more pain in the left foot. MRI lumbar spine performed 23-April-2017 showing huge extruded disc L5-S1 central wide-based more to the right, causing severe segmental stenosis.

On examination, the patient is in agonizing pain, limping with exaggerated scoliotic stance. SLRS was 25 degrees with pain in both sides. There is weak dorsiflexion left foot -4/5, right foot 4/5 and planterflexion right foot 4/5.

Decompressive laminectomy L5 and upper sacrum with foraminotomy both S1 roots. The extruded disk was removed lateral to the axilla of the right S1 root. Bilateral cleaning of L5-S1 disc space was performed. The right S1 root was shifted up and lateral and the cleaning was performed subaxillary. Using MultiGen, bipolar motor stimulation of the left S1 was achieved with 0.9 V. The right s1 was achieved with 0.7 V. Waiting 4 minutes the same procedure repeated and bipolar motor stimulation of the left S1 was achieved with 0.8 V, bipolar motor stimulation of the right S1 was achieved with 0.6 V. A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to both S1 roots was achieved using 4 bended catheters 10 mm exposed length. Further bipolar motor stimulation of the left S1 was achieved with 0.7 V, bipolar motor stimulation of the right S1 was achieved with 0.4 V. Routine closure of the wound.

Smooth postoperative recovery. The power of both feet normalized and he was sciatica free. He was sent to the ward.

The patient still having an estimated postoperative recurrence around 7%, because the disc space is still not shallow.

This is the 115th case using the BPRF mode with MultiGen. This procedure regained routine acceptance.  It became a usual part of the spine and peripheral nerves surgery. Click here for reference.

It still unclear to evaluate the differences of pre and post application motor responses. The only sure thing that it tells that the electrodes did not migrate during the procedure and the nerve is functioning properly. Here there was considerable improvement of the threshold of stimulation power of motor stimulation of the both S1 roots.

With accumulation of data, it became clear that the irritated nerve with aberrant currents running in the C fibers up, not only causing no change or elevation of the required voltage to achieve motor response, but they could cause the preoperative weakness. Ablation of such currents results in facilitation of the motor response and improvement of function with disappearance of pain.

It is unclear why the roots have several motor response with different patients, despite the fact that the neurological status is the same and the anesthesia protocol also the same.

It could be that the nerve is recovering minute by minute after decompression and this can explain why the motor conductivity is improving after the BPRF application, which require 4 minute session. This trail was performed intentionally to confirm or exclude such this conclusion. Here we noticed that the motor response of both nerves improved after first stimulation, confirming that the improvement came as a result of previous stimulation and BPRF still adding further improvement.