The patient was operated by me 16-June-2015 for severe LCS with spondylolisthesis L3-4, L4-5, during which decompressive laminectomy L1 down to L5 with transpedicular fixation of L2-3-4 was performed.  The patient came many times to the clinic showing slight improvement of the neurologic status and several times underwent full investigations for his surgery. The patient then came to the clinic 06-March-2017 complaining of heaviness of the left leg with LBP in the sacral area.

On examination, the patient is still using crutches for walking. SLRS was 80 degrees left side with pain. There is weak left quadriceps muscle -4/5. Previously all the time it was 5/5. Dorsi and planterflexion right foot 3/5 as previous all examination. The power of all other muscles both legs were 5/5. There is pain of the left lower chest cage.

he patient was sent for investigations and MRI lumbar spine performed showing as be huge extruded disc D12-L1 with central upward migration, more to the left. The patient was sent for cardiac evaluation.

Decompressive laminectomy D12. The left lateral mass of D12-L1 was severely compressing the spinal cord. It was drilled out with removal of the bony and ligamenteous elements. Foraminotomy left Th12 root. Inspection of the disc space and around the root, above the disc space and below did not reveal any disc extrusion. Using MultiGen, bipolar motor stimulation of the left Th12 was achieved with 1.3 V. A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to left Th12 root was achieved using 2 bended catheters 10 mm exposed length. Further bipolar motor stimulation of the left Th12 was achieved with 0.6 V with more vivid response. Routine closure of the wound.

Smooth postoperative recovery. The power of left quadriceps muscle became better. He was sent to the ward.

The patient has very shallow disc space, that extrusion is impossible to occur. The patient before surgery was diagnosed as having extrusion, but during surgery, it became evident that the compression was from the bony ligamenteous elements of the left facet joint.

After fusion of L2-3-4, the stress point was added to the D12-L1 segment and it was mostly the cause of such event.

This is the 112th 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 there was dramatic improvement of the threshold of stimulation power of motor stimulation of the left D12 root.

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 4-5 minutes session.