The patient was operated by me 11-January-2018 for extruded disc L4-5 with right foraminal and downward migration and the right drop foot fully recovered. The patient then came 14-March-2018 complaining of right sciatica down to the the big toe right foot with right hip pain. The power of the right foot was normal and sensation was preserved. SLRS was 90 degrees with pain in the right. The patient was sent for investigations and MRI lumbar spine performed the same day showing a small recurrence at the L4-5 right side. CRP was 10 mg/L and ESR was 30 mm/h. It was decided to keep the patient in conservative treatment. The patient the came 18-April-2018 telling that there is no improvement form the conservative treatment. 

On examination, the patient is limping with scoliotic stance. SLRS was 90 degrees in the right with pain and 90 degrees in the left with pain shooting the the right. There was weak dorsiflexion right foot 4/5. The patient was sent for investigation and MRI lumbar spine performed 18-April-2018 showing enlargement of the recurrence of L4-5 with right foraminal occlusion. ESR was 17 mm/h and CRP was <5 mg/L.

Neurolysis of right L5 root was achieved. The extruded recurrent disk was removed lateral to the axilla from right side. Right sided intradiscal cleaning of L4-5 disc space was performed. For the future project, an hexagonal Allen key No 4 was with greater resistance than the previous surgery was going inside the annulus fibrosis defect. Using MultiGen, bipolar motor stimulation of the right L5 root was achieved with 1.2 V. 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 was achieved with 1.0 V. Routine closure of the wound.

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

The patient still having an estimated postoperative recurrence around 7%, because the disc space is still not shallow. It seems that recurrence among diabetic patients is higher than non diabetic.

This is the 148th 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 root after application was better.

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.

Here the case demonstrate that the effect of BPRF is limited for 2-3 months after application at best.