The patient came to the clinic 20-August-2016  complaining of left sciatica down to all toes for 4 months. MRI lumbar spine performed 22-April-2016 showing extruded disk of L5-S1 with huge left downward migration.

On examination: the patient is now not limping with exaggerated scoliotic stance. SLRS was 15 degrees with pain left side. There is weak dorsiflexion left foot 3/5 and planterflexion same foot -4/5 with difficult setting. There is hypalgesia above the left knee and below. The left AJ was absent.

The patient was sent for investigations and MRI performed 20-August-2016 showing the same extrusion. Dynamic studies ruled out overmobility.

Foraminotomy left S1 was achieved. The extruded disk was removed lateral to the axilla from the left side and left sided cleaning of L5-S1 was performed. The depth of cleaning was 40 mm.  Using MultiGen, bipolar motor stimulation of left S1 root was achieved with 0.4 V. A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to 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 0.4 V in the left with more brisk response. Routine closure of the wound.

Smooth postoperative recovery. The power of left foot normalized and he was sciatica free. He 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 72nd 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 considerable decrease of the threshold of stimulation power of motor stimulation after the procedure in the right side.

With accumulation of data, it became clear that the irritated nerve with aberrant currents running in the C fibers up, not only causing 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.