The patient came to the clinic 27-October-2016 complaining of LBP with bilateral sciatica for 6 years. The last 10 days numbness of the left L5 root territory. MRI lumbar spine performed 24-October-2016 showing spondylolisthesis L4-5 with bulge all diski lumbar spine. Dynamic studies showing G II spondylolisthesis L4-5. The patient is a known diabetic with arterial hypertension.

On examination, the patient is not limping now. She has exaggerated scoliotic stance. SLRS was 75 degrees with pain left side. There is weak dorsiflexion both feet -4/5 right and 3/5 left. The left AJ is absent.

The patient was sent for cardiac consultation.

Skeletonization of L3-4-5 down to the transverse processii of L4 and L5. Check of overmobility was positive for L4-5. The facets were fractured and have mobile fragments which were removed. Transpedicular distraction-reduction-fixation of L4-5 using XIA 3 system with 3 monoaxial screws 6.5x50 to L5 and L4 and one 6.5x35 mm to the left side of L5. Bipolar motor stimulation of left L5 was achieved with 1.8 V. The right L5 root was responding to 1.5 V. A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to both L5 roots was achieved using 4 bended catheters 10 mm exposed length lateral to the isthmi and the rods . Further motor stimulation done to the same roots and the response was 1.3 V to the left L5 root, with more brisk response and 1.3 V to the right L5 root. Cross connector was applied 50 mm Slight distraction reduction was applied. Routine closure of the wound. All stages of surgery were performed under C-arm guidance.

Smooth postoperative recovery. The power of both feet normalized. She was sent to the ward.

The patient has bulge diski several levels, that cannot explain the agonizing pain. The segmental overmobility is the determinant factor for pain generation, which needs correction.

This is the 92d 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 in one root and improvement of the other.

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.

In this case the roots were reached externally, lateral to the isthmi and the rods.