Percutaneous Cervical Nucleoplasty vs. Pulsed Radio Frequency of the Dorsal Root Ganglion in Patients with Contained Cervical Disk Herniation; A Prospective, Randomized Controlled Trial

Comparison between ultrasound-guided monopolar and bipolar pulsed radiofrequency treatment for refractory chronic cervical radicular pain: A randomized trial

BACKGROUND

Many patients complain of chronic cervical radicular pain, and pulsed radiofrequency (PRF) is known to have a positive effect for alleviating neuropathic pain.

OBJECTIVES

In the present study, we used ultrasound (US) guidance and compared the effects of monopolar PRF with those of bipolar PRF in patients with chronic cervical radicular pain refractory to repeated transforaminal epidural steroid injections.

METHODS

Sixty-six patients with chronic cervical radicular pain were included in this study. Patients were randomly assigned to one of the two groups: monopolar or bipolar PRF group (n= 33 per group). Pain intensity was evaluated using a numeric rating scale (NRS) at pretreatment, and at 1 and 3 months after the treatment. Target stimulation site was the extraforaminal nerve root.

RESULTS

Compared to the pretreatment NRS scores, patients in both groups showed a significant decrease in NRS scores at 1 and 3 months after the treatment. Reductions in the NRS scores over time were significantly larger in the bipolar PRF group. Three months after the treatment, 18 patients (54.5%) in the monopolar PRF group and 27 (81.8%) in the bipolar PRF group reported successful pain relief (pain relief of ⩾50%).

CONCLUSIONS

US-guided PRF can be an effective interventional technique for the management of chronic refractory cervical radiculopathy. Moreover, bipolar PRF has better treatment outcome than monopolar PRF.

Safety of Conventional and Pulsed Radiofrequency Lesions of the Dorsal Root Entry Zone Complex (DREZC) for Interventional Pain Management: A Systematic Review

Study Design

Systematic literature review.

Objective

The goal of this systematic review is to assess the clinical safety and potential complications of conventional and pulsed radiofrequency ablations targeting dorsal root entry zone complex (DREZC) components in the treatment of chronic pain.

Background

There is a growing popularity for the use of radiofrequency ablation (RFA) techniques targeting DREZC components by pain management physicians for an increasing variety of indications. To date, we lack a systematic review to describe the safety and the type of complications associated with these procedures.

Methods

This was a systematic literature review. This systematic search was limited to peer-reviewed literature using “radiofrequency ablation” as a search keyword using PubMed’s database for manuscripts published between inception and December 2020. Abstracts that involved the application of radiofrequency currents, of any modality, to DREZC components for the treatment of pain were included for full-text review. Search was limited to original data describing clinical outcomes following RFA performed for pain indications only, involving the DREZC components outlined above, in human subjects, and written in English. The primary outcomes were complications associated with conventional RFA and pulsed radiofrequency ablation (PRF). Complications were categorized as type 1 (persistent neurological deficits or other serious adverse events, defined as any event that resulted in permanent of prolonged injury; type 2 (transient neuritis or neurological deficits, or other non-neurological non-minor adverse event); type 3 (minor adverse events (e.g., headache, soreness, bruising, etc.).

Results

Of the 62 selected manuscripts totaling 3157 patients, there were zero serious adverse events or persistent neurological deficits reported. A total of 36 (1.14%) transient neurological deficits, cases of transient neuritis, or non-minor adverse events like uncomplicated pneumothorax were reported. A total of 113 (3.58%) minor adverse events were reported (bruising, transient site soreness, headache).

Conclusions

This systematic review indicates that the use of RFA lesion of the DREZC for interventional pain management is very safe. There were no serious adverse effects with a sizable sample of randomized controlled trial (RCT), prospective observational, and retrospective studies.

Pharmacological and non-pharmacological treatments for neuropathic pain: Systematic review and French recommendations

Neuropathic pain remains a significant unmet medical need. Several recommendations have recently been proposed concerning pharmacotherapy, neurostimulation techniques and interventional management, but no comprehensive guideline encompassing all these treatments has yet been issued. We performed a systematic review of pharmacotherapy, neurostimulation, surgery, psychotherapies and other types of therapy for peripheral or central neuropathic pain, based on studies published in peer-reviewed journals before January 2018. The main inclusion criteria were chronic neuropathic pain for at least three months, a randomized controlled methodology, at least three weeks of follow-up, at least 10 patients per group, and a double-blind design for drug therapy. Based on the GRADE system, we provide weak-to-strong recommendations for use and proposal as a first-line treatment for SNRIs (duloxetine and venlafaxine), gabapentin and tricyclic antidepressants and, for topical lidocaine and transcutaneous electrical nerve stimulation specifically for peripheral neuropathic pain; a weak recommendation for use and proposal as a second-line treatment for pregabalin, tramadol, combination therapy (antidepressant combined with gabapentinoids), and for high-concentration capsaicin patches and botulinum toxin A specifically for peripheral neuropathic pain; a weak recommendation for use and proposal as a third-line treatment for high-frequency rTMS of the motor cortex, spinal cord stimulation (failed back surgery syndrome and painful diabetic polyneuropathy) and strong opioids (in the absence of an alternative). Psychotherapy (cognitive behavioral therapy and mindfulness) is recommended as a second-line therapy, as an add-on to other therapies. An algorithm encompassing all the recommended treatments is proposed.

Percutaneous cervical discectomy: retrospective comparison of two different techniques

AIM

To compare clinical success and patient satisfaction of percutaneous cervical nucleoplasty (PCN) and percutaneous cervical discectomy (PCD) in contained cervical disc herniation treatment.

MATERIALS AND METHODS

We retrospectively identified 50 consecutive patients in our institution: 24 underwent the PCD treatment and 26 patients were treated by the PCN procedure. All patients complained of radicular pain with or without neck pain; diagnosis of contained cervical disc herniation was obtained by MRI; all patients had received conservative therapy which did not result in symptom improvement. Exclusion from our series consisted of patients who had undergone previous surgery at the indicated level, or those with myelopathy, or those in whom more than a sole herniation was treated in the same session. Overall procedure time, fluoroscopy time, radiation dose and complications were recorded. The MacNab scale score was used to assess clinical success in terms of pain relief at 2- and 6-month follow-up. After 4-6 months, a cervical MRI was obtained in 24 patients.

RESULTS

Neither major nor minor complications were reported. Regarding patient satisfaction, overall median modified MacNab score was excellent both at 2 and 6 months after treatment. No significant statistical difference was found in mean modified MacNab score at 2 and 6 months among patients grouped by treatment choice (p = 0.319 and 0.847, respectively); radiation dose was inferior in PCN group than in PCD, with no significant statistical difference.

CONCLUSION

PCD and PCN were found to be safe and effective in terms of pain relief in contained cervical herniation treatment.

Long-Term Clinical Outcomes of Percutaneous Cervical Nucleoplasty for Cervical Degenerative Diseases with Neck Pain and Cervical Vertigo

BACKGROUND

Good short- and mid-term clinical efficacy of percutaneous cervical nucleoplasty (PCN) for cervical degenerative diseases (CDD) with neck pain has been reported. However, few studies have assessed its long-term influence in patients with both neck pain and cervical vertigo. This study aimed to evaluate the curative efficacy of PCN for CDD with neck pain and cervical vertigo with minimum of 6 years of follow-up.

METHODS

Inpatients who underwent PCN for CDD with neck pain and cervical vertigo between April 2010 and March 2013 were enrolled. Clinical outcomes were assessed using the Cervical Vertigo Evaluation Scale (CVES); greater CVES scores reflected less impairment. Additional open surgeries were recorded.

RESULTS

Among 40 patients, 100% completed the 1-year short-term and 3-year mid-term follow-up (FU); 85% completed the 6-year long-term FU. Clinical effective rates were 67.5%, 67.5%, and 52.94% at short-, mid-, and long-term FU, respectively. CVES scores were greater than the preoperative CVES scores at all FU timepoints (P < 0.01). However, the CVES score was lower at the final FU than at the 3-year FU (P < 0.05). The neck pain score significantly decreased over time and was lower than the cervical vertigo score at the final FU (P > 0.05). Reoperation rates were 1/40 (2.50%) and 3/34 (8.82%) at mid- and long-term FU, respectively.

CONCLUSIONS

PCN in patients with CDD neck pain and cervical vertigo showed satisfactory clinical efficacy at short- and mid-term FU, and it was fair at long-term FU. Thus, PCN could be a complementary operation for CDD.

Microglial BDNF, PI3K, and p-ERK in the Spinal Cord Are Suppressed by Pulsed Radiofrequency on Dorsal Root Ganglion to Ease SNI-Induced Neuropathic Pain in Rats

Background

Pulsed radiofrequency (PRF) on the dorsal root ganglion (DRG) has been applied to alleviate neuropathic pain effectively, yet the mechanisms underlying pain reduction owing to this treatment are not clarified completely. The activated microglia, brain-derived neurotrophic factor (BDNF), phosphatidylinositol 3-kinase (PI3K), and phosphorylated extracellular signal-regulated kinase (p-ERK) in the spinal cord were demonstrated to be involved in developing neuropathic pain. Also, it has been just known that PRF on DRG inhibits the microglial activation in nerve injury rats. Here, we aim to investigate whether PRF treatment could regulate the levels of BDNF, PI3K, and p-ERK in the spinal cord of rats with spared nerve injury (SNI) via suppressing the spinal microglia activation to ease neuropathic pain.

Methods

The rats with SNI were intrathecally treated with minocycline (specific microglia inhibitor) or same volume of dimethyl sulfoxide once daily, beginning from 1 h before nerve transection to 7 days. PRF was applied adjacent to the L₄-L₅ DRG of rats with SNI at 45 V for 6 min on the seventh postoperative day, whereas the free-PRF rats were treated without PRF. The withdrawal thresholds were studied, and the spinal levels of ionized calcium-binding adapter molecule 1 (Iba1), BDNF, PI3K, and p-ERK were calculated by western blot analysis, reverse transcription-polymerase chain reaction, and immunofluorescence.

Results

The paw withdrawal mechanical threshold and paw withdrawal thermal latency decreased in the ipsilateral hind paws after SNI, and the spinal levels of Iba1, BDNF, PI3K, and p-ERK increased on day 21 after SNI compared with baseline (P < 0.01). An intrathecal injection of minocycline led to the reversal of SNI-induced allodynia and increase in levels of Iba1, BDNF, PI3K, and p-ERK. Withdrawal thresholds recovered partially after a single PRF treatment for 14 days, and SNI-induced microglia hyperactivity, BDNF upregulation, and PI3K and ERK phosphorylation in the spinal cord reduced on D14 due to the PRF procedure.

Conclusion

Microglial BDNF, PI3K, and p-ERK in the spinal cord are suppressed by the therapy of PRF on DRG to ease SNI-induced neuropathic pain in rats.

Effectiveness of pulsed radiofrequency treatment on cervical radicular pain: A meta-analysis

BACKGROUND

Cervical radicular pain is a challenging medical problem in terms of therapeutic management. Recently, pulsed radiofrequency (PRF) stimulation on the dorsal root ganglion (DRG) has been used to control several types of chronic pain. However, its effect on cervical radicular pain is still not well studied. To conduct a meta-analysis of available clinical studies on PRF treatment in patients with cervical radicular pain induced by cervical spine disease that was not responsive to other conservative treatments.

METHODS

A comprehensive database search was conducted on PubMed, Embase, Cochrane Library, and SCOPUS. We included studies published up to August 31, 2017, that fulfilled our inclusion and exclusion criteria. The pain degrees measured using visual analog scale (VAS) at pretreatment and after PRF on the DRG were collected for the meta-analysis. The Cochrane Collaboration's Handbook and Newcastle-Ottawa scale were used for the methodological quality assessments of included studies. The meta-analysis was performed using the Comprehensive Meta-analysis Version 2.

RESULTS

A total of 67 patients from one RCT study, 2 prospective observational studies, and one retrospective study were included in this meta-analysis. The pooled data of the 4 included studies showed that overall VAS after the PRF treatment was significantly reduced (P ≤ .001). In the subgroup analysis according to follow-up evaluation time points, the pain was significantly reduced at 2 weeks, 1 month, 3 months, and 6 months after the procedure (2 weeks: P = .02; 1, 3, and 6 months: P < .001).

CONCLUSION

According to the results of the meta-analysis, the use of PRF on the DRG is effective for alleviating cervical radicular pain, which was unresponsive to oral medications, physical therapy, or epidural steroid injection.

A comprehensive review of pulsed radiofrequency in the treatment of pain associated with different spinal conditions

OBJECTIVE

The objective of this review was to evaluate the efficacy of pulsed radiofrequency (PRF) treatment of pain associated with different spinal conditions. The mechanisms of action and biological effects are shortly discussed to provide the scientific basis for this radiofrequency modality.

METHODS

We systematically searched for clinical studies on spinal clinical conditions using PRF. We searched the MEDLINE (PubMed) database. We classified the information in one table focusing on randomized controlled trials (RCTs) and other types of studies. Date of last electronic search was October 2016.

RESULTS

We found four RCTs that evaluated the efficacy of PRF on cervical radicular pain and five observational studies. Two trials and three observational studies were conducted in patients with facet pain. For disc-related pathology, we found one RCT with PRF applied intradiscally and three RCTs for dorsal root ganglia PRF modulation lumbosacral radicular pain. For sacroiliac joint pain, spondylolisthesis, malignancies and other minor spinal pathology, limited studies were conducted.

CONCLUSION

From the available evidence, the use of PRF to the dorsal root ganglion in cervical radicular pain is compelling. With regard to its lumbosacral counterpart, the use of PRF cannot be similarly advocated in view of the absence of standardization of PRF parameters, enrolment criteria and different methods in reporting results; but, the evidence is interesting. The use of PRF in lumbar facet pain was found to be less effective than conventional RF techniques. For the other different spinal conditions, we need further studies to assess the effectiveness of PRF. Advances in knowledge: The use of PRF in lumbar facet pain was found to be less effective than conventional RF techniques. For the other different spinal conditions, we need further studies to assess the effectiveness of PRF.