The patient came to the clinic 05-January-2017 complaining of LBP and left sciatica. He was operated elsewhere for PLD L5-S1 for left sciatica 2 years ago. The patient started to complain of LBP 4 months after surgery with exacerbation of LBP with left sciatica the last 3 months. MRI lumbar spine performed 23-October-2016 showing recurrent disc L5-S1 left side.

On examination, the patient is in agonizing pain, limping with exaggerated scoliotic stance. SLRS was 20 degrees in the left side. There is weak left foot dorsiflexion -4/5, planterflexion same foot 4/5.

The patient was sent for new investigations and MRI lumbar spine performed 05-January-2017 showing huge recurrent disc L5-S1 with left up and downward migration. Dynamic studies were uneventful.

Left S1 neurolysis and foraminotomy was achieved. The Level of the L5-S1 was identified with scarolysis of the left S1 root. The extruded disk was removed lateral to the axilla under the S1 root. Left sided cleaning of L5-S1 was performed. Using MultiGen, bipolar motor stimulation of the left S1 was achieved with 2.5 V. A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to the left S1 root was achieved using 2 bended catheters 10 mm exposed length. Further motor stimulation done to the same root and the response was 2.3 V in the left S1 with more brisk response. Routine closure of the wound.

Smooth postoperative recovery. The power of the left foot improved and he was sciatica free. He was sent to the ward.

The patient still having an estimated postoperative re-recurrence less than 7%, because the disc space is shallower than before.

This is the 99th 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 tell that the electrodes did not migrate during the procedure and the nerve is functioning properly. Here there was considerable improvement 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.

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 anaesthesia protocol also the same. In this case adhesions could be a factor for initial high voltage requirement to achieve motor response.