Pulsed Radiofrequency Spinal Cord Neuromodulation for Residual Symptoms after Cervical Surgery
Authors: Buric Josip , Omar-Pasha Omar , Sinan Tarik Saud 
Published: May 2015

Introduction

Cervical decompression, discectomy, fusion, and arthroplasty are treatment modalities of choice for various pathological conditions of cervical spine. Occasionally after these procedures, some degree of neck pain, paresthesia, and/or palsy may still be reported by patients. Pulsed radiofrequency (PRF) neuromodulation of spinal cord dorsal root entry zone, pregangliar and postgangliar nerve root parts, is a well-known invasive pain therapy modality used for a variety of pain symptoms. This study was done to evaluate if a single session, PRF neuromodulation, might be effective in the treatment of residual symptoms after cervical surgical procedures.

Materials and Methods

Thirty-eight patients from three different clinical settings were included in the study. Eighteen patients have been previously submitted to one- or two-level anterior discectomy and interbody fusion, 10 patients to two or more level anterior discectomy, decompression, and fusion, 7 patients had a one- to two-level arthroplasty performed, while the rest had a posterior decompression with or without instrumented fusion. Upon surgery, 22 patients reported some residual symptoms mainly of neck pain, radiating pain to scapular and/or shoulder area, and 15 of them had only or also paresthesia and/or pain radiating to one or both upper limbs. Four patients also had some degree of residual palsy that did not improve completely after the surgery. The neuromodulation procedure was performed not less than 3 months after the surgery (mean time from surgery to PRF treatment was 4.5 months). In all the cases, the PRF procedure was done by Pasha-catheter that was introduced inside the vertebral channel at the midthoracic level, interlaminary, and under local anesthesia only. In the cases of neck pain, extradural treatment of dorsal root entry zones, pregangliar and occasionally postgangliar nerve fibers at multiple levels from C2 to D1, was done bilaterally. In the cases of symptoms radiating to the upper limbs, the treatment was mainly focused on the side of the symptoms and the treatment was centered on dorsal root entry zones and preganglionic fibers. When the residual palsy was present, the preferred treatment was intrathecal treatment of the dorsal root entry zone and the ganglion area. The mean treatment duration was 58 ± 14 minutes. Except when an intradural modality of treatment was performed, all the patients were discharged on the same day after a 6-hour in-hospital observation. The intradurally treated patients were discharged the next morning. In 3 cases, posttreatment headache was reported in the first 24 hours, while in 10 cases the pain was at the introduction site. No short- or long-term complications were observed.

Results

At 2-month follow-up, 34 patients reported significant improvement in pain levels while at 1-year follow-up, 29 patients were still reporting significant improvement in pain levels as compared with preoperative status. Preoperative mean VAS value for all the patients was 5.5 ( ±  2) and the 1-year reduction evaluation was 1.5 ( ±  1). Out of the four patients with residual palsy, two patients were found almost free of the palsy, one patient did not improve at all, and another had just partial improvement in the strength.

Conclusion

The PRF neuromodulation of the spinal cord and gangliar structures seems to be reasonably useful for the treatment of the residual pain and neurological symptoms after different cervical surgical procedures.