The patient came to the clinic 19-September-2023 complaining of agonizing right sciatica for 2 months, numbness both feet more the right with inability to walk due to pain. MRI lumbar spine done 03-September-2023 showing severe LCS L3-4 bad quality. Dynamic studies ruled out overmobility. The patient is diabetic  and underwent discectomy L5-S1 2011 for right sciatica.

On examination, there is no scoliosis but limping. SLRS was 90 degrees without pain both sides. There is weak dorsiflexion right foot 3/5 with hypalgesia right L5 and S1 territories.

The patient was sent for investigations and MRI lumbar spine done 21-September-2023 showing severe LCS L3-4 with normal pelvis MRI.

Decompressive laminectomy L3 and upper third of L4 with foraminotomy both L4 roots with inspection of the disc space right side. Using MultiGen, bipolar stimulation of the right L4 root was responding to 1.0 Volt, bipolar stimulation of the left L4 root was not responding even to 4.0 Volts. A bipolar pulsed mode RF with 42 Celsius, 240 sec, 2 Hz and 20 msec duration to both L4 roots  was achieved using 4 bended catheters 10 mm exposed length. Further bipolar stimulation of the right L4 root was responding to 0.8 Volts, bipolar stimulation of the left L4 root was responding to 2.8 Volts. The patient was put in Reverse Trendelenburg position with Valsalva maneuver and hyperventilation. No CSF leak. The power of the feet improved. He was sent to the ward.

Too early now.

The patient has severe weak right foot with sciatica and severe stenosis of L3-4.

This is the 265th case using the MultiGen. This procedure regained routine acceptance.  It became a usual part of the spine and peripheral nerves surgery. Click here for reference. The patient showed considerable improvement of the motor stimulation after BPRF. The unusual thing that the left nerve was electrically in bad condition in relative to the right, which clinically is suffering.

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 was 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 5 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 or above the level of the axilla.

Before doing motor stimulation in peripheral nerve surgery with tourniquet. always remove the tourniquet before performing motor stimulation.