The patient came to the clinic 15-July-2019 complaining of neck pain for 4 years with exacerbation last 2 months with MRI cervical done 16-July-2018 showing bulge C5-6 and C6-7  with mild weak extension left hand  and was treated conservatively. The patient then came 25-August-2021 with LBP and left sciatica for 3 months and was operated 09-July-2021 elsewhere without benefit. MRI done 08-July-2021 before surgery showing extruded disc L4-5 with left foraminal occlusion and repeated 22-August-2021 with the same picture as before surgery. He is diabetic and hypertensive in treatment.

On examination, the patient is not limping. SLRS was 70 degrees right side with pain and 15 degrees left side with more pain. There is weak dorsi and planterflexion left foot 3/5 with hypalgesia left L5 and S1 territories.

The patient was sent for investigations and cardio consultation. ESR was 33 mm/h, for what Zinnat was started.

The old wound was used. Neurolysis of the left L5 root. The extruded disc was removed lateral to the axilla and left sided intradiscal cleaning L4-5 was achieved. The root was short, for what fenestration attempted at first surgery failed. Using MultiGen, bipolar motor stimulation of the left L5 root was achieved even with 2.1 Volts, A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to the left L5 root  was achieved using 2 bended catheters 10 mm exposed length. Further bipolar motor stimulation of the left L5 root was achieved with 1.5 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. He 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 224th 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 nerve improved dramatically after BPRF, because it seems the root was severely compressed.

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 at least 5 minute 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.