The patient came to the clinic 29-August-2016 complaining of LBP for 15 days with left sciatica for 10 days down to gastrocnemius left leg. MRI lumbar spine performed 23-August-2016 showing bulge L4-5 and central extruded disk L5-S1 more to the left. The patient is a known diabetic in baby aspirin.

On examination, the patient was not limping without scoliotic stance. SLRS was 85 degrees with pain in the left. There is weak dorsiflexion left foot -4/5.

The patient was advised to keep in conservative treatment, which failed and came back 06-September-2016 telling that his complains still the same.

The patient was sent for investigations and dynamic studies ruled out overmobility of L5-S1 segment. He was advised to stop aspirin for at least 5 days.

Left foraminotomy S1 was achieved. The extruded disk was removed lateral to the axilla of left S1 root. Due to severe compression, the latero-anterior wall of the root was lacking dura with the arachnoid bulging through it, The defect was coagulated to shrink the defect and Valsalva maneuver ruled out CSF leak.  Left sided cleaning of L5-S1 was performed. The depth of cleaning was 40 mm.  Using MultiGen, bipolar motor stimulation of left S1 was achieved with 1.3 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 1.0 V in the left S1 root with more brisk response. The dural defect was covered with layer of muscle. Routine closure of the wound.

Smooth postoperative recovery. The power of the left foot regained full strength and 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 80th 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 decrease of the threshold of stimulation power of motor stimulation after the procedure in the left S1 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.

Nor MRI or CT-scan can give precise real picture of the morphological event. This case is a demonstration, of how the the extrusion having a look of non considerable extrusion and in reality it was stuck to the root, that it caused dural defect.