The patient came to the clinic 27-October-2022 complaining of LBP for 50 years with left shoulder and both knees pain. Exacerbation of LBP with bilateral sciatica the last year. MRI lumbar spine done 16-July-2022 showing severe stenosis L3-4 and L4-5 with bulge L5-S1. CRP was 24 mg /L and ESR was 54 mm/h. The patient cannot walk more than 5 meters with intermittent claudication both feet.

On examination, the patient is walking with crutches and help. SLRS was 40 degrees both sides with pain. Hypalgesia both L5 and S1 both feet with weak dorsiflexion both feet 3/5. Normal micturition and defecation. Severe O.A. both knees with pain left knee. The patient was given antibiotic and pain killers and medications to improve the knee joints and to be seen by cardiologist. The son came 18-January-2023 with cardio report permitting to perform surgery and covered her with concor and Blopress. He was asked to repeat ESR and CRP which were normal.

Decompressive laminectomy L4, upper half of L5 and lower half of L3. Foraminotomy both L4, L5 both sides. Using MultiGen, bipolar stimulation of the right L4 root was responding to 1.5 Volts. The left L4 responded to 1.3 Volts, bipolar stimulation of the right L5 root was not responding even to 3.5 Volts. The left L5 responded to 2.6 Volts.  A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to the all exposed roots was achieved using 4 bended catheters 10 mm exposed length in 2 sessions. Further bipolar stimulation of the right L4 root was responding to 1.4 Volts. The left L4 responded to 1.3 Volts, bipolar stimulation of the right L5 root was responding to 3.5 Volts. The left L5 responded to 2.4 Volts. The patient was put in Reverse Trendelenburg position with Valsalva maneuver and hyperventilation. No CSF leak. The power of the feet improved. She was sent to the ward. The patient is allergic to Pethidine.

MultiGen

Too early now.

The earlier the decompression of progressing lumbar canal stenosis the better the outcome.

This is the 250th 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 nerves 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 was 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 or above the level of the axilla.

Both L5 roots responded to higher voltage denoting their severe anatomic compromise.