The patient was operated by me 22-December-2005 for huge extruded disc L5-S1 with left downward migration. The patient then came 11-January-2020 complaining of LBP with left sciatica without neurological deficit. MRI lumbar spine performed 12-January-2020 showing soft recurrence of L5-S1 left side. She was advised to keep in conservative treatment. The patient then came 07-July-2021 telling that the last 3 weeks the LBP and left sciatica reappeared with exacerbation at the last 6 days. She is diabetic for 3 years, in medication.

On examination, the patient is limping with exaggerated scoliotic stance . SLRS was 90 degrees both sides without pain. There is weak dorsiflexion left foot 4/5 with dysesthesia left S1 territory.

The patient was sent for investigation and MRI of the lumbar spine done 17-July-2021 showed recurrence of L5-S1 of hard consistency with left upward migration.

The old wound was used. Left L5-S1 hemiflavotomy with extended neurolysis of the left S1 root. The extruded disc was removed by drilling the bony extrusion lateral to the axilla and left sided intradiscal cleaning L5-S1 was achieved.  The left side of the lamina was drilled off superiorly to identify the upper migrating piece so as not to miss it. Using MultiGen, bipolar motor stimulation of the left S1 root was achieved even with 1.1 Volts, A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to the left S1 root  was achieved using 2 bended catheters 10 mm exposed length. Further bipolar motor stimulation of the left S1 root was achieved with 0.6 Volts. The patient was put in Reverse Trendelenburg position with Valsalva maneuver and hyperventilation. No CSF leak. A piece of muscle tissue was used to cover the root territory to minimize the postoperative scar formation and prevent postoperative CSF leak. Routine closure of the wound. Smooth postoperative recovery. The power of the left foot dramatically improved. She was sent to the ward.

MultiGen

Too early now.

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

This is the 220th 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 motor stimulation of the affected nerves improved dramatically after BPRF.

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.

After the 172d case, the elevation of motor stimulation above 5 V was abandoned to avoid delayed dural tear with subsequent CSF leak, which take place at the contact at the lower electrode shaft with the dura below the level of the axilla.

This rare case with extradural arachnoid cyst with extruded disc simultaneously compressing the running by root.