The patient came to the clinic 07-March-2018 complaining of neck pain for 3 days with left sciatica for 1 month after slipping from stair with LSS-X-ray performed at that time showing spondylolisthesis L4-5.

On examination, the patient is limping with exaggerated scoliotic stance. There is neck pain when turning the head to the left, down, up and bending the head to the left shoulder. There is weak extension left hand and left triceps 4/5. SLRS was 45 degrees in the right with pain and 15 degrees in the left with pain. There is weak dorsi and planterflexion left foot 4/5 and both quadriceps and left iliopsoas 4/5.

The patient was sent for investigations and MRI whole spine done 08-March-2018 showing normal cervical spine, the spinal cord shifted to the right at D4-7, huge extruded disc L3-4 with left downward migration, extruded disc L4-5 with left upward migration with spondylolisthesis L4-5. Dynamic studies showed retrolisthesis L3-4 and spondylolisthesis L4-5.

Skeletonization of L3,4,5 down to the lateral processes. Transpedicular fixation of L3-4,5 using monoaxial 4 screws 6.5x45 mm to L3 and L5 and OSI reduction 2 screws 6.5x45 mm to L4 vertebrae. After inserting the screws motor stimulation 8 V was applied to all screws and there was n response. Foraminotomy of left L4 and 5 roots was achieved. The extruded disk L3-4, L4-5 were removed lateral to the axilla from left side. Left sided intradiscal cleaning of L3-4, L4-5 disc spaces was performed. Insertion of FIDIS TLIF cage 10x10x30 to the L4-5 disc space. Using MultiGen, bipolar motor stimulation of the left L5 root was achieved with 1.0V. 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 1.0V. Routine closure of the wound.

Smooth postoperative recovery. The power of the left leg became normal. He was sciatica free. He was sent to the ward.

The operation was difficult and took 7 hours, because the patient has massive bleeding due to huge amount of pain-killers, for what it was necessary to give him Vit K during surgery and 2 units packed RBCs and 4 units FFP after surgery in the ward.

It seems that these changes were related to his trauma.

This is the 147th 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 stimulation power of motor stimulation of the root after application was the same.

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.