The patient was operated by me 22-January-2017 for recurrent disc L4-5 with right upward migration and after the surgery continued to complain of right buttock pain. The pain was agonizing one and when walking there was no sciatica, but when returning to sleep in bed and turning to the right side, the pain was agonizing. MRI done 23-January-2017 showed huge fresh re-recurrence of the same disc.

The wound was opened. Exploration of the wound. Further foraminotomy of right L4 root. The extruded disk from the L4-5 was reaching and compressing the axilla of right L4 root. It was missed during the first surgery, then removed now after what the root became lax. Further right sided cleaning of L4-5 was performed. Foraminotomy of the right L5 root was performed. Using MultiGen, bipolar motor stimulation of the right L4 was achieved with 0.8 V.  The right L5 root responded to 1.5 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 motor stimulation done to the last root and the response was 1.3 V with more brisk response. Routine closure of the wound.

Smooth postoperative recovery. The patient was sciatica free. He was sent to the ward.

The patient still having an estimated postoperative third recurrence less than 7%, because the disc space is shallower than before. The recurrence immediately after surgery is very rare and during 37 years , it is the fourth case making the estimated recurrence in this case around 0.04%.

This is the 103d 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 tell that the electrodes did not migrate during the procedure and the nerve is functioning properly. Here there was considerable improvement of the threshold of stimulation power of motor stimulation after the 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 anaesthesia protocol also the same. In this case adhesions could be a factor for initial high voltage requirement to achieve motor response, but adhesions were relatively minimal around the root, for what considerable improvement was achieved.

The root motor response of right L4 in previous surgery was 1.8 V which improved to 0.6 V and now is 0.8 V. It means that the effect of the manipulation still persisting after 48 hours after surgery.

The clinical picture of recurrence or missed fragment with application of BPRF is different from the usual recurrence without BPRF.