The patient was operated by me 18-June-2009 for extruded disc L4-5 with left downward migration. The patient then came to the clinic 14-November-2018 complaining of LBP with right sciatica for three months after RTA. MRI lumbar spine performed 30-September-2017 showing bulge L4-5. The patient performed elsewhere discectomy C5-6 3 years ago. The patient now is hypertensive in Concor and Co-Diovan. He is in Zyloric for gout.

On examination: He is limping with exaggerated scoliotic stance. SLRS was 20 degrees right side with severe pain and 80 degrees in the left without pain. There was weak dorsiflexion right foot 3/5.

The patient was sent for investigations and MRI lumbar spine performed 14-November-2018 showing huge recurrent extruded disc L4-5 with right downward migration causing severe segmental stenosis. All other investigations were within normal limits.

Before the surgery the patient claimed that he lost feeling of the right foot. Foraminotomy right L5 root with removal of the extrusion lateral to the axilla and right sided cleaning L4-5 disc space. Using MultiGen, bipolar motor stimulation of the right L5 root was achieved with 2.8 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 2.3 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 the right foot was unable to evaluate because the patient is telling he cannot feel the right foot. He still having dysesthesia of the right foot. He was sent to the ward.

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

This is the 171st 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 root after application improved dramatically, but the motor stimulation was high before and after application, denoting the severe damage of the root.

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.