The patient came to the clinic 26-June-2019 complaining of LBP with right sciatica down to the left foot with numbness all toes right foot for 45 days. MRI done 26-May-2019 showing severe degenerative spine with stenosis of L2-3, L3-4, wedging of L3 and severe compression of the right L5 root at L4-5 level, which could be due to facet part compression of extruded disc. The patient claim that she was seen by me more than 25 years with this degenerative spine and she was recommended t keep in conservative treatment. Before the recent event, she could walk more than 2 Km and she never complain of LCS manifestations. She is hypertensive for 25 years and receiving L-thyroxin 150 microgram for 10 years.

On examination: She is in agonizing pain, limping and scoliotic stance. SLRS was 80 degrees right side with pain and 90 degrees in the left without pain. There was weak dorsiflexion right foot -3/5, planterflexion right foot 4/5.

The patient was sent for investigations: Dynamic studies ruled out overmobility. Lab investigations were uneventful. Ct-scan ruled out presence of isthmolysis or presence of elements of overmobility. The patient was advised for surgery and start immediately Zinnat 500 twice daily to decrease the possibility of postoperative infection and to be seen by cardiologist.

Right L4-5 foraminotomy. All the compressive elements were drilled out and inspection of the disc showed extruded disc L4-5 with severe compression of the right L5. The extruded small disc was removed and the disc space was very shallow. Extended foraminotomy of the right L5 roots was achieved.  Using MultiGen, bipolar motor stimulation of right L5 root was achieved with 2.7 Volts. A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to the right L5 root  was achieved using 2 bended catheters 10 mm exposed length. Further bipolar motor stimulation of the right L5 root was achieved even with 1.8 V. The patient was put in Reverse Trendelenburg position with Valsalva maneuver. No CSF leak. Routine closure of the wound.

Smooth postoperative recovery. The power of the right foot normalized and the sciatica disappeared. She was sent to the ward.

The old changes of the spine were ignored and surgery was directed to the recent cause of her complains.

This is the 181st 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 tells that the electrodes did not migrate during the procedure and the nerve is functioning properly. Here the threshold of stimulation power of motor stimulation of the severely affected nerves improved dramatically after 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 anesthesia protocol also the same.

It could be that the nerve is recovering minute by minute after decompression and this can explain why the motor conductivity is improving after the BPRF application, which require 4 minute session in most cases.

After the 172d case, the elevation of motor stimulation above 5 V was abandoned to avoid delayed dural tear with subsequent CSF leak, which take place at the contact at the lower electrode shaft with the dura below the level of the axilla.