The patient came to the clinic 24-August-2016 complaining of LBP with bilateral sciatica for 7 years down to the heels of both feet with numbness both feet more the left. She can walk less than 150 meters and the condition is deteriorating. The patient is a known diabetic with arterial hypertension.

On examination, the patient was limping with exaggerated scoliotic stance. SLRS was 60 degrees with pain in both sides. There is weak dorsiflexion both feet 4/5 with hypalgesia both L5 roots territories more the left mixed with diabetic neuropathy.

The patient was sent for neurophysiologic investigations and MRI lumbar spine performed the same day showing spondylolisthesis L4-5 with severe segmental stenosis. Dynamic studies confirmed the overmobility of L4-5 segment. The patient was sent for cardiologic evaluation and stopped baby aspirin for 7 days.

Skeletonization of L4,5 and upper sacrum until the lateral processes of L4 and L5 were dissected. Transpedicular fixation was achieved using Zodiac system AlphatecSpine with 2 reduction screws to L4 level 6.5x40 mm, one polyaxial screw 6.5x45 mm left side, one polyaxial screw 7.5x40 mm to the right at L5 level. Decompressive laminectomy L4 lamina with removal of all flail fragments. Foraminotomy L4 and L5 roots both sides. Using MultiGen, bipolar motor stimulation of right L4 was achieved with 1.2 V, right L5 root was achieved with 2.0 V, left L4 root- 0.7 V, left L5 root 0.9 V. A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to both L4 and L5 roots was achieved using 4 bended catheters 10 mm exposed length in 2 settings. Further motor stimulation done to the same roots and the response was 1.1 V in the left L4 and 1.8 V in the right L5 root with more brisk response. The left L4 root respond to 0.7 V and the left L5 root to 0.9 V. Bended 2 rods 5.5 mm with 50 mm length with cross connector were used to obtain fusion and slight reduction. The harvested bone was melt and applied lateral to the rods. All stages of surgery were guided using the C-arm. Routine closure of the wound.

Smooth postoperative recovery. The power of both feet dramatically improved and she was sciatica free. She was sent to the ward.

The patient has a progressive spondylolisthesis, which needs surgical correction.

This is the 76th 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 all  roots.

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.

ILLICO retractor cannot be applied in this surgery.