The patient came to the clinic 08-August-2021 complaining of LBP for 1 years with right sciatica down to the right S1 territory. MRI lumbar spine done 31-March-2021 showing huge extruded disc L2-3 and bulge L5-S1. The patient noticed urination problems the last 3 months. The patient is diabetic and hypertensive for 5 years under treatment.

On examination, the patient in agonizing pain, limping with exaggerated scoliotic stance. SLRS was 90 degrees both side with pain and the pain in the left side shooting to the right leg. There is weak dorsiflexion both feet.

The patient sent for investigations, which done the same day showing the huge extruded disc L2-3 with right upper compression and left lower compression with severe segmental stenosis. Dynamic studies showed minimal spondylolisthesis L4-5 without gross overmobility.

Using the C-arm. the L2-3 level was identified and decompressive laminectomy L2-3 was done with foraminotomy both L 3 roots. Inspection of the disc of L2-3 both side was uneventful and was decided not to violate it. Using MultiGen, bipolar motor stimulation of the right L3 root was achieved with 3.0 Volt, the left L3 root was achieved with 1.7 Volts. A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to the left L4 root  was achieved using 2 bended catheters 10 mm exposed length. Further bipolar motor stimulation of the right L3 root was achieved with 1.8 Volt, the left L3 root was achieved with 1.3 Volts. The patient was put in Reverse Trendelenburg position with Valsalva maneuver and hyperventilation. No CSF leak. A piece of fat tissue was used to cover the root territory to minimize the postoperative scar formation. Routine closure of the wound. Smooth postoperative recovery. The power of the feet improved. He was sent to the ward.

MultiGen

Too early now.

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

This is the 222d 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 did not change 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.