The patient was operated by me 21-November-2011 for spondylolisthesis of L5-S1. Then his son came to the clinic 06-June-2022, telling that his father is complaining of severe LBP and bilateral sciatica the last 2 weeks with exacerbation the last 5 days. MRI lumbar spine bad quality performed 16-May-2022 suggesting huge extruded disc L4-5 and severe segmental stenosis. He was advised to repeat investigations with complete protocols. The patient is a known hypertensive, diabetic with diabetic nephropathy and using during night Oxygen-generator for sleep apnea? He is using L-thyroxin for several years.

The patient then came 07-June-2022 with new MRI showing huge extruded disc L4-5 wide-based with upper right and lower left extrusion. Dynamic studies ruled out over-mobility. The upper right screw is broken at the mid-shaft, of no significance. ESR was 45 mm/h.

On examination, the patient is in agonizing pain, limping with scoliotic stance. Walking with the help of others. SLRS was 5 degrees right side with pain and 80 degrees left side with less pain. There is weak dorsiflexion both feet 4/5 with hypalgesia right L5 and S1 territories. 

The patient was sent for cardio, pulmonary, endocrine  and nephrology consultations.

Decompressive laminectomy L4-5 with foraminotomy both L5 roots. Bilateral removal of the extrusion and bilateral cleaning L4-5 disc space. Using MultiGen, bipolar stimulation of the right L5 root was responding to 2.1 Volts. Bipolar stimulation of the left L5 root was not responding even to 4.0 Volts. A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to both L5 roost  was achieved using 4 bended catheters 10 mm exposed length. Further bipolar stimulation of the right L5 root was responding to 1.8 Volts. Bipolar stimulation of the left L5 root was responding to 3.5 Volts. The patient was put in Reverse Trendelenburg position with Valsalva maneuver and hyperventilation. No CSF leak. The patient because he was obese and the Wilson frame, small to him showed massive bleeding from the epidural veins, for what 2 units blood were asked to be given after surgery. Smooth postoperative recovery. The power of the both feet improved. He was sent to the ward.

Too early now.

The recurrence rate here is around 7%, because the disc space is not shallow.

This is the 241st 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. The nerve improved moderately in motor stimulation after performed 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 5 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.

The patient due to many diseases, was considered to be high risk for G.A.