The patient's relatives came to the clinic 04-December-2019 telling that he was complaining of weak both feet with numbness for several months. MRI lumbar spine performed 29-June-2019 showing severe lumbar canal stenosis L4-5 with possible wide based extrusion and possible spondylolisthesis. The patient felt down 1 month ago and got right transtrochanteric fracture and fixation was performed without traction of the leg. After then the patient lost ability to walk and using Foley's catheter. The patient is a known diabetic, underwent open heart surgery 3 years ago.

The patient was sent for investigations and overmobility of the spine was ruled out. Cardio evaluation was considered moderate risk for surgery. The patient was advised to stop anticoagulant for 7 days and given Zinnat 500 twice daily, because ESR was 48 mm/h and CRP was 20 mg/dL.

On examination before surgery: The patient is bedridden and has weak dorsiflexion both feet 4/5. Sensation preserved but complaining of numbness both feet and pain at the previous performed right hip surgery with Foley's catheter. The right lower limb is shorter than the left about 5 cm.

Decompressive laminectomy L4-5 with foraminotomy both L5 roots. Inspection of the L4-5 disc space revealed not to violate it both sides. Using MultiGen, bipolar motor stimulation of the left L5 root was achieved with 1.5 Volts. Bipolar motor stimulation of the right L5 root was achieved with 4.0 Volts. 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. Further bipolar motor stimulation of the left L5 root was achieved with 1.4 Volts. Bipolar motor stimulation of the right L5 root was achieved with 4.0 Volts. The patient was put in Reverse Trendelenburg position with Valsalva maneuver and hyperventilation. No CSF leak. Routine closure of the wound.

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

This is the 191st 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 nerve did not change, but the less affected improved.

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.