The patient came was operated by me 03-November-2013 for extruded disk L4-5 with right downward migration. The patient was doing well until she came to the clinic 19-September-2016 telling that the last 2 months got LBP with left sciatica. MRI lumbar spine performed 07-September-2016 showing extruded disk L3-4 with left downward migration.

On examination, the patient was limping with exaggerated scoliotic stance. SLRS was 45 degrees with little pain in the right and 30 degrees with more pain in the left.. There is weak left quadriceps muscle 4/5.

Left hemilaminectomy L3 and remnants of L4 was achieved. Foraminotomy left L4 root was achieved. The extruded disk was removed lateral to the axilla under the L4 root, which was located relatively low. Left sided cleaning of L3-4 was performed. The depth of cleaning was 35 mm.  Using MultiGen, bipolar motor stimulation of left L4 was achieved with 1.3 V. A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to left L4 root was achieved using 2 bended catheters 10 mm exposed length. Further motor stimulation done to the same root and the response was1.3 V in the left L4 with more brisk response. Routine closure of the wound.

Smooth postoperative recovery. The power of left leg improved and she was sciatica free. She was sent to the ward.

The patient still have an estimated postoperative recurrence around 7%, because the disc space is still not shallow.

This is the 82d case using the BPRF mode with MultiGen. This procedure regained routine acceptance.  It became a usual part of the spine 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 tell that the electrodes did not migrate during the procedure and the nerve is functioning properly. Here there was no change of the threshold of stimulation power of motor stimulation after the 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.