The patient came to the clinic 03-September-2018 complaining of LBP  with right sciatica for 2 months with numbness dorsum right foot. The patient is a known epileptic with Tegretol CR 200 twice daily for 3 years.

On examination: She is limping with exaggerated scoliotic stance. SLRS was 20 degrees right side with pain and 30 degrees in the left shooting to the right leg. There was weak dorsiflexion right foot 2/5 with weak planterflexion same foot 3/5.

The patient was sent for investigations and MRI lumbar spine performed 03-September-2018 showing extruded disc L4-5 with right downward migration.

Right L4 partial hemilaminectomy with partial hemilaminectomy of L5. Foraminotomy right L5 root with removal of the extrusion lateral to the axilla in three big separated pieces and right sided cleaning L4-5 disc space. Using MultiGen, bipolar motor stimulation of the right L5 root was achieved with 2.0 V. A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to right L5 root was achieved using 2 bended catheters 10 mm exposed length. Further bipolar motor stimulation of the right L5 root was achieved with 0.9 V. The patient was put in Reverse Trendelenburg position with Valsalva maneuver. No CSF leak. Routine closure of the wound.

Smooth postoperative recovery. The power of right foot became normal. She was sciatica free. She was sent to the ward.

There is still an estimated postoperative recurrence around 7%, because the disc space height is not shallow.

This is the 167th 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 the threshold of stimulation power of motor stimulation of the affected roots after application improved dramatically.

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 in most cases.