Radiofrequency procedures in chronic pain

Successful Thoracic Spinal Cord Stimulator Implantation in a High-Risk Patient With Intractable Intercostal Neuralgia: A Case Report

Intercostal neuralgia can be debilitating and extremely difficult to treat despite multi-modal therapies. The literature describing the role of neuromodulation in patients with intercostal neuralgia is scarce. In this medically challenging case report, we describe a 56-year-old male with a near complete resolution of intractable chronic intercostal neuralgia, secondary to traumatic rib fractures and multiple surgical interventions, with a single lead thoracic spinal cord stimulator (SCS) implant. Neuromodulation therapies should be considered as a viable option for this patient population.

The Mechanism of Action between Pulsed Radiofrequency and Orthobiologics: Is There a Synergistic Effect?

Radiofrequency energy is a common treatment modality for chronic pain. While there are different forms of radiofrequency-based therapeutics, the common concept is the generation of an electromagnetic field in the applied area, that can result in neuromodulation (pulsed radiofrequency—PRF) or ablation. Our specific focus relates to PRF due to the possibility of modulation that is in accordance with the mechanisms of action of orthobiologics. The proposed mechanism of action of PRF pertaining to pain relief relies on a decrease in pro-inflammatory cytokines, an increase in cytosolic calcium concentration, a general effect on the immune system, and a reduction in the formation of free radical molecules. The primary known properties of orthobiologics constitute the release of growth factors, a stimulus for endogenous repair, analgesia, and improvement of the function of the injured area. In this review, we described the mechanism of action of both treatments and pertinent scientific references to the use of the combination of PRF and orthobiologics. Our hypothesis is a synergic effect with the combination of both techniques which could benefit patients and improve the life quality.

Cervical facet joint platelet-rich plasma in people with chronic whiplash-associated disorders: A prospective case series of short-term outcomes

Objective

To explore the safety and feasibility of a single autologous injection of platelet-rich plasma (PRP) in cervical facet joints of people with chronic WAD and facet-mediated pain, and explore the association between pain relief reported with diagnostic medial branch blocks (MBBs) and 3-months post-PRP.

Design

A prospective case series of people with chronic whiplash-associated disorders and cervical facet joint mediated pain in a community setting.

Interventions

A single autologous PRP injection was provided to cervical facet joints under ultrasound and fluoroscopic guidance.

Measures

Adverse events were recorded one-week, and measures of pain (numerical pain rating scale - NPRS) and disability (Neck Disability Index - NDI) were collected prior to and 3-months following cervical facet joint PRP. People not reached for follow-up were considered failures for worst-case analysis. The correlation between percentage response to diagnostic cervical medial branch blocks (MBBs) and percentage pain relief reported at 3-months was also investigated.

Results

Forty-four people (82% female; mean age (SD): 45.2 (10.8) years) underwent cervical facet joint PRP. There was a significant improvement in pain and disability following PRP. Seventy percent of people exceeded MCID for pain. For NDI scores, 80% of people exceeded MCID. Forty-one percent of people reported greater than 50% relief of pain 3-months post-cervical facet joint PRP.There was no significant correlation between percentage relief of pain with cervical MBBs and percentage relief of pain 3-months post-PRP (r ​= ​0.06, p ​= ​0.73).There were no adverse events reported.

Conclusion

In people with chronic WAD and facet-mediated pain, preliminary data suggests that PRP is safe and it is feasible to move forwards with randomized studies to further investigate efficacy and effectiveness.

Awake CT-guided percutaneous stylomastoid foramen puncture and radiofrequency ablation of facial nerve for treatment of hemifacial spasm

OBJECTIVE

Hemifacial spasm (HFS) is a debilitating neuromuscular disorder with limited treatment options. The current study describes a novel minimally invasive procedure that provided effective and sustained relief for patients with HFS. The authors provide a detailed description of the awake CT-guided percutaneous radiofrequency ablation (RFA) of the facial nerve for treatment of HFS, and they examine its clinical efficacy. This is the first time in the literature that this procedure has been applied and systematically analyzed for HFS.

METHODS

Patients with a history of HFS were recruited between August 2018 and April 2020. Those with a history of cerebellopontine lesions, coagulopathy, ongoing pregnancy, cardiac pacemaker or defibrillator implants, or who declined the procedure were excluded from the study. Fifty-three patients who met the study criteria were included and underwent awake CT-guided RFA. Under minimal sedation, a radiofrequency (RF) needle was used to reach the stylomastoid foramen on the affected side under CT guidance, and the facial nerve was localized using a low-frequency stimulation current. Patients were instructed to engage facial muscles as a proxy for motor monitoring during RFA. Ablation stopped when the patients' hemifacial contracture resolved. Patients were kept for inpatient monitoring for 24 hours postoperatively and were followed up monthly to monitor resolution of HFS and complications for up to 19 months.

RESULTS

The average duration of the procedure was 32-34 minutes. Postoperatively, 91% of the patients (48/53) had complete resolution of HFS, whereas the remaining individuals had partial resolution. A total of 48 patients reported mild to moderate facial paralysis immediately post-RFA, but most resolved within 1 month. No other significant complication was observed during the study period. By the end of the study period, 5 patients had recurrence of mild HFS symptoms, whereas only 2 patients reported dissatisfaction with the treatment results.

CONCLUSIONS

The authors report for the first time that awake CT-guided RFA of the facial nerve at the stylomastoid foramen is a minimally invasive procedure and can be an effective treatment option for HFS.

Systematic Review of Radiofrequency Ablation for Management of Knee Pain

PURPOSE OF REVIEW

Chronic pain of the lower extremity remains challenging to manage. Radiofrequency ablation procedure applies heat to nerve fibers with the goal of mitigating chronic pain conditions of the knee. However, the clinical efficacy has not yet been adequately established. The goal of this review paper is to report the use of radiofrequency ablations in the treatment of osteoarthritis of the knee.

RECENT FINDINGS

PubMed and the Cochrane Controlled Trials Register were searched (final search 28 February 2018) using the MeSH terms "radiofrequency ablation," "neurolysis," "radiofrequency therapy," "pain syndrome," "analgesia," and "pain" in the English literature. Bibliographies of the published papers were screened for relevance to lower extremity radiofrequency ablation therapies. The quality of selected publications was assessed using the Cochrane risk of bias instrument. Of the 923 papers screened, 317 were further investigated for relevance. Our final search methodology yielded 19 studies that investigated the use of radiofrequency ablation at the knee. Of these 19 studies, there were four randomized control trials, two non-randomized control trials, three prospective studies, two retrospective studies, one case-control study, one technical report, and seven case reports. In summary, the data available suggests radiofrequency ablation as a promising and efficacious with all 19 studies revealing significant short- and long-term pain reductions in patients with knee pain.

A Systematic Review of Radiofrequency Treatment of the Ankle for the Management of Chronic Foot and Ankle Pain

BACKGROUND

Chronic pain of the lower extremity remains challenging to manage. Radiofrequency treatment applies heat to nerve fibers with the goal of mitigating chronic pain conditions. The clinical efficacy has not yet been adequately established for pathologies of the ankle and foot. In this review paper, we report the use and efficacy of radiofrequency treatment applied to foot and ankle pain.

RECENT FINDINGS

PubMed and the Cochrane Controlled Trials Register were searched (final search 30 March 2018) using the MeSH terms "radiofrequency ablation," "neurolysis," "radiofrequency therapy," "pain syndrome," "analgesia," "plantar heel pain," "plantar fascitis," and "chronic pain" in the English literature. Of the 23 papers screened, 18 were further investigated for relevance. Our final search methodology yielded 15 studies that investigated the use of radiofrequency treatment at the ankle. Of these 15 studies, there were three randomized control trials, four prospective studies, three retrospective studies, and five case reports. The quality of selected publications was assessed using the Cochrane risk of bias instrument. The evidence from our studies suggests that radiofrequency treatment can be used safely for the management foot and ankle pain. The technique (continuous vs pulsatile), temperature, location of treatment, and duration of administration need more thorough evaluation. Randomized control trials are needed to establish the efficacy and safety profile of radiofrequency ablation and its long-term benefits in patients with chronic pain of the foot and ankle.

CONCLUSION

The evidence from our studies suggests that radiofrequency treatment can be used safely for the management foot and ankle pain. The technique (continuous vs pulsatile), temperature, location of treatment, and duration of administration need more thorough evaluation. Randomized control trials are needed to establish the efficacy and safety profile of radiofrequency ablation and its long-term benefits in patients with chronic pain of the foot and ankle.

Interventional Anesthetic Methods for Pain in Hematology/Oncology Patients

This article reviews anesthetic interventional approaches to the management of pain in hematology and oncology patients. It includes a discussion of single interventions including peripheral nerve blocks, plexus injections, and sympathetic nerve neurolysis, and continuous infusion therapy through implantable devices, such as intrathecal pumps, epidural port-a-caths, and tunneled catheters. The primary objective is to inform members of hematology and oncology care teams regarding the variety of interventional options for patients with cancer-related pain for whom medical pain management methods have not been effective.

Short-Term Efficacy of Pulsed Radiofrequency Thermal Stimulation on Acupoints for Chronic Low Back Pain: A Preliminary Study of a Randomized, Single-Blinded, Placebo-Controlled Trial

Background

The objective of this study was to evaluate the pain-relief efficacy of thermal stimulation induced by a pulsed radiofrequency (PRF) thermal stimulation applied to acupoints (APs) in patients with low back pain (LBP). The study was designed as a randomized, single-blinded, placebo-controlled trial. Methods. Fifty-six LBP patients whose minimum pain intensity score on a visual analogue scale (VAS, 0-100 mm) was more than 30 mm were randomly allocated to either the placebo-controlled or the treatment group at a 1:1 ratio. The treatment and placebo-controlled groups received PRF thermal stimulation plus cupping therapy and cupping therapy only, respectively. Each patient was scheduled to receive a total of three treatment sessions over one week with allowing a window up to 4 days. Six of the 13 predefined APs were selected differently for each session depending on the change in patient's symptoms and intensity of pain. The primary outcome was the mean difference between the placebo-controlled and treatment group of VAS changes from the baseline to the end of the follow-up period.

Results

The patients' reported VAS scores from baseline to the end of follow-up (average: 9.8 days) were significantly decreased by 8.036 points (two-sided 95% CI, -11.841 to -4.231) and 13.393 points (two-sided 95% CI: 17.198 to -9.588) in the treatment and the placebo-controlled groups, respectively. However, the change in VAS scores between the treatment group and the placebo-controlled group was not significantly different (2.015 mm, two-sided 95% CI: -5.288 to 9.317).

Conclusion

The trial results indicated that treatment with either PRF thermal stimulation with cupping therapy or cupping therapy alone effectively relieved LBP. The efficacy of PRF thermal stimulation combined with cupping therapy was not superior to that of cupping therapy alone. Trial registration number: Clinical Research Information Service (KCT0002137). The trial was registered retrospectively on 10 November, 2016.

3D navigation of endoscopic rhizotomy at the lumbar spine

We present a detailed description of the surgical technique and the preliminary results of an endoscopic denervation for patients with chronic low back pain (CLBP) originating from the facet joints (FJ). Endoscopic denervation of the medial branches of the dorsal rami supplying the FJ has recently been appraised as providing excellent intraoperative visualization and long term pain relief for these patients. Conventional endoscopic rhizotomy has been expanded to include a the precise localization of 3D navigation. A surgical description and the results of our first four patients treated with 3D navigated endoscopic rhizotomy (3DNER) are presented. Four patients with a mean age of 59years and a follow-up time of 2months were included. All patients reported pain reduction in the immediate postoperative period, while three patients (75%) had long lasting relief. The patient without persisting relief had previously sustained a lumbar disc prolapse and only achieved minor pain relief with preoperative FJ infiltration, compared to the significant relief that was seen in the other patients. In contrast to conventional rhizotomy, 3DNER enables the surgeon to ablate more precisely and extensively, which is especially useful if scar tissue is present from previous injuries or surgeries. When successful, this technique may provide long lasting pain relief, especially if the preoperative FJ infiltrations are followed by a substantial pain reduction.

The interaction between the composition of preinjected fluids and duration of radiofrequency on lesion size

BACKGROUND

Clinical recommendations for the duration of radiofrequency (RF) delivery have been based on no-fluid design, which may not be representative of clinical practice where fluid preinjection occurs. The purpose of this study was to examine the interaction between the preinjection of fluids of differing compositions and duration of RF on lesion size. The variability of lesion development under different preinjection conditions was also examined across the RF lesion duration.

METHODS

Monopolar RF was performed with ex vivo chicken samples for 180 seconds without fluid preinjection or with fluid preinjected. Nonionic and ionic fluids were investigated. Lesion size parameters and and power levels were measured every 10 seconds. The surface area and efficiency index were calculated.

RESULTS

The preinjection of specific fluid increased the maximum mean surface area. Lesion growth continued throughout the entire lesion cycle. When all groups were considered together, the largest mean surface area occurred at 180 seconds. The preinjection of specific fluids altered the rate of lesion growth and the time required to achieve maximum lesion size in a fluid-specific manner. Significant variability was documented in the rate and amount of lesion growth under each condition. Extending lesioning time resulted in reduced lesion variability.

CONCLUSIONS

Fluid preinjection alters both final lesion size and the time required to achieve maximum lesion size. Extending the duration of RF lesion cycle beyond 90 seconds when fluid is preinjected allows for lesion size to be maximized while limiting lesion size variability, both of which assist in successfully lesioning a targeted nerve.

Brain abscess after percutaneous therapy for trigeminal neuralgia

We report a case of brain abscess following the percutaneous treatment for trigeminal neuralgia. This procedure envisages the access with a needle into the middle cranial fossa through the oral cavity. Thus, in this case, the bacterial infection can be more likely ascribed to the possible contamination of the needle inside the oral cavity rather than to other frequent and more controllable causes of infection like an imperfect sterilization of surgical instruments or an inadequate antiseptic preparation of both operator's hands and patient's skin. The subsequent brain abscess was treated with antibiotic therapy (Vancomycin 2 gr a day and Meropenem 8 g a day for 22 days before the surgical procedure and 30 days after, until complete normalization of laboratory parameters, clinical parameters, and neurological symptoms) and surgical drainage, although the culture of the abscess capsule and the purulent material resulted sterile. In conclusion, the percutaneous therapy for trigeminal neuralgia can be objectively related to risks, even if performed by expert hands. Therefore, it is important that the patient should be advised regarding risks/benefits and/or septic complications of such procedures, even if they occur very seldom. An association of surgery and antibiotic therapy results as effective treatment for this pathologic condition.

Modulation of Cervical Facet Joint Nociception and Pain Attenuates Physical and Psychological Features of Chronic Whiplash: A Prospective Study

OBJECTIVE

To investigate changes in clinical (physical and psychological) features of individuals with chronic whiplash-associated disorder who had previously undergone cervical radiofrequency neurotomy at the time point when the effects of radiofrequency neurotomy had dissipated and pain returned.

DESIGN

Prospective cohort observational trial of consecutive patients.

SETTING

Tertiary spinal intervention centre in Calgary, Alberta, Canada.

PATIENTS

A total of 53 consecutive individuals with chronic whiplash-associated disorder.

METHODS

Individuals underwent radiofrequency neurotomy and were assessed before radiofrequency neurotomy, at 1 and 3 months postprocedure, and then after the return of pain (approximately 10 months postprocedure).

MAIN OUTCOME MEASUREMENTS

Quantitative sensory tests (pressure; thermal pain thresholds; brachial plexus provocation test), nociceptive flexion reflex, and motor function (cervical range of movement; craniocervical flexion test) were measured. Self-reported disability, psychological distress, pain catastrophization, and posttraumatic stress disorder symptoms also were measured.

RESULTS

Upon the return of pain after radiofrequency neurotomy, levels of disability increased (P < .0001), and were no different to those before radiofrequency neurotomy (P = .99). There also was a significant deterioration in quantitative sensory testing measures and reduced cervical range of motion after the return of pain (all P < .05); all approaching values were recorded before radiofrequency neurotomy (P > .22). There were no significant changes in pressure hyperalgesia (P > .054) or craniocervical flexion test performance (P > .07) after the return of pain. Psychological distress and pain catastrophizing increased significantly after the return of pain (P < .01), and again were no different than measures taken prior to radiofrequency neurotomy (P > .13). However, there was no difference in number or severity of posttraumatic stress symptoms after the return of pain (P > .30).

CONCLUSIONS

Physical and psychological features of chronic whiplash-associated disorder are modulated dynamically with cervical radiofrequency neurotomy. These findings indicate that peripheral nociception is involved in the manifestations of chronic whiplash-associated disorder in this cohort of individuals.

A systematic review of peripheral nerve interventional treatments for chronic headaches

OBJECTIVE

This study aimed to systematically compare the outcomes of different types of interventional procedures offered for the treatment of headaches and targeted toward peripheral nerves based on available published literature.

BACKGROUND

Multiple procedural modalities targeted at peripheral nerves are being offered to patients for the treatment of chronic headaches. However, few resources exist to compare the effectiveness of these modalities. The objective of this study was to systematically review the literature to compare the published outcomes and effectiveness of peripheral nerve surgery, radiofrequency (RF) therapy, and peripheral nerve stimulators for chronic headaches, migraines, and occipital neuralgia.

METHODS

A broad literature search of the MEDLINE and CENTRAL (Cochrane) databases was undertaken. Relevant studies were selected by 2 independent reviewers and these results were narrowed further by the application of predetermined inclusion and exclusion criteria. Studies were assessed for quality, and data were extracted regarding study characteristics (study type, level of evidence, type of intervention, and number of patients) and objective outcomes (success rate, length of follow-up, and complications). Pooled analysis was performed to compare success rates and complications between modality types.

RESULTS

Of an initial 250 search results, 26 studies met the inclusion criteria. Of these, 14 articles studied nerve decompression, 9 studied peripheral nerve stimulation, and 3 studied RF intervention. When study populations and results were pooled, a total of 1253 patients had undergone nerve decompression with an 86% success rate, 184 patients were treated by nerve stimulation with a 68% success rate, and 131 patients were treated by RF with a 55% success rate. When compared to one another, these success rates were all statistically significantly different. Neither nerve decompression nor RF reported complications requiring a return to the operating room, whereas implantable nerve stimulators had a 31.5% rate of such complications. Minor complication rates were similar among all 3 procedures.

CONCLUSIONS

Of the 3 most commonly encountered interventional procedures for chronic headaches, peripheral nerve surgery via decompression of involved peripheral nerves has been the best-studied modality in terms of total number of studies, level of evidence of published studies, and length of follow-up. Reported success rates for nerve decompression or excision tend to be higher than those for peripheral nerve stimulation or for RF, although poor study quantity and quality prohibit an accurate comparative analysis. Of the 3 procedures, peripheral nerve stimulator implantation was associated with the greatest number of complications. Although peripheral nerve surgery seems to be the interventional treatment modality that is currently best supported by the literature, better controlled and normalized high-quality studies will help to better define the specific roles for each type of intervention.

A retrospective review and treatment paradigm of interventional therapies for patients suffering from intractable thoracic chest wall pain in the oncologic population

INTRODUCTION

Tumors invading the chest wall and pleura are often incurable, and treatment is targeted toward palliation of symptoms and control of pain. When patients develop tolerance or side effects to systemic opioid therapy, interventional techniques can better optimize a patient's pain. We performed a retrospective review of 146 patients from April 2004 to January 2014 who underwent diagnostic and therapeutic procedures for pain relief. Using four patients as a paradigm for neurolytic approaches to pain relief, we present a therapeutic algorithm for treating patients with intractable thoracic chest wall pain in the oncologic population.

MATERIAL AND METHODS

For each patient, we describe the use of intercostal/paravertebral nerve blocks and neurolysis, pulsed radiofrequency ablation (PRFA) of the thoracic nerve roots, or intrathecal pump placement to successfully treat the patient's chest wall pain. Analysis of 146 patient charts is also performed to assess effectiveness of therapy.

RESULTS

Seventy-nine percent of patients undergoing an intercostal nerve diagnostic blockade (with local anesthetic and steroid) stated that they had improved pain relief with 22% having prolonged pain relief (average of 21.5 days). Only 32% of successful diagnostic blockade patients elected to proceed to neurolysis, with a 62% success rate. Seven patients elected to proceed to intrathecal drug delivery.

DISCUSSION

Intercostal nerve diagnostic blockade with local anesthetic and steroid may lead to prolonged pain relief in this population. Furthermore, depending on tumor location, we have developed a paradigm for the treatment of thoracic chest wall pain in the oncologic population.

Interventions for treating pain and disability in adults with complex regional pain syndrome

BACKGROUND

There is currently no strong consensus regarding the optimal management of complex regional pain syndrome although a multitude of interventions have been described and are commonly used.

OBJECTIVES

To summarise the evidence from Cochrane and non-Cochrane systematic reviews of the effectiveness of any therapeutic intervention used to reduce pain, disability or both in adults with complex regional pain syndrome (CRPS).

METHODS

We identified Cochrane reviews and non-Cochrane reviews through a systematic search of the following databases: Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects (DARE), Ovid MEDLINE, Ovid EMBASE, CINAHL, LILACS and PEDro. We included non-Cochrane systematic reviews where they contained evidence not covered by identified Cochrane reviews. The methodological quality of reviews was assessed using the AMSTAR tool.We extracted data for the primary outcomes pain, disability and adverse events, and the secondary outcomes of quality of life, emotional well being and participants' ratings of satisfaction or improvement. Only evidence arising from randomised controlled trials was considered. We used the GRADE system to assess the quality of evidence.

MAIN RESULTS

We included six Cochrane reviews and 13 non-Cochrane systematic reviews. Cochrane reviews demonstrated better methodological quality than non-Cochrane reviews. Trials were typically small and the quality variable.There is moderate quality evidence that intravenous regional blockade with guanethidine is not effective in CRPS and that the procedure appears to be associated with the risk of significant adverse events.There is low quality evidence that bisphosphonates, calcitonin or a daily course of intravenous ketamine may be effective for pain when compared with placebo; graded motor imagery may be effective for pain and function when compared with usual care; and that mirror therapy may be effective for pain in post-stroke CRPS compared with a 'covered mirror' control. This evidence should be interpreted with caution. There is low quality evidence that local anaesthetic sympathetic blockade is not effective. Low quality evidence suggests that physiotherapy or occupational therapy are associated with small positive effects that are unlikely to be clinically important at one year follow up when compared with a social work passive attention control.For a wide range of other interventions, there is either no evidence or very low quality evidence available from which no conclusions should be drawn.

AUTHORS' CONCLUSIONS

There is a critical lack of high quality evidence for the effectiveness of most therapies for CRPS. Until further larger trials are undertaken, formulating an evidence-based approach to managing CRPS will remain difficult.

Interventions for treating pain and disability in adults with complex regional pain syndrome

BACKGROUND

There is currently no strong consensus regarding the optimal management of complex regional pain syndrome although a multitude of interventions have been described and are commonly used.

OBJECTIVES

To summarise the evidence from Cochrane and non-Cochrane systematic reviews of the effectiveness of any therapeutic intervention used to reduce pain, disability or both in adults with complex regional pain syndrome (CRPS).

METHODS

We identified Cochrane reviews and non-Cochrane reviews through a systematic search of the following databases: Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects (DARE), Ovid MEDLINE, Ovid EMBASE, CINAHL, LILACS and PEDro. We included non-Cochrane systematic reviews where they contained evidence not covered by identified Cochrane reviews. The methodological quality of reviews was assessed using the AMSTAR tool.We extracted data for the primary outcomes pain, disability and adverse events, and the secondary outcomes of quality of life, emotional well being and participants' ratings of satisfaction or improvement. Only evidence arising from randomised controlled trials was considered. We used the GRADE system to assess the quality of evidence.

MAIN RESULTS

We included six Cochrane reviews and 13 non-Cochrane systematic reviews. Cochrane reviews demonstrated better methodological quality than non-Cochrane reviews. Trials were typically small and the quality variable.There is moderate quality evidence that intravenous regional blockade with guanethidine is not effective in CRPS and that the procedure appears to be associated with the risk of significant adverse events.There is low quality evidence that bisphosphonates, calcitonin or a daily course of intravenous ketamine may be effective for pain when compared with placebo; graded motor imagery may be effective for pain and function when compared with usual care; and that mirror therapy may be effective for pain in post-stroke CRPS compared with a 'covered mirror' control. This evidence should be interpreted with caution. There is low quality evidence that local anaesthetic sympathetic blockade is not effective. Low quality evidence suggests that physiotherapy or occupational therapy are associated with small positive effects that are unlikely to be clinically important at one year follow up when compared with a social work passive attention control.For a wide range of other interventions, there is either no evidence or very low quality evidence available from which no conclusions should be drawn.

AUTHORS' CONCLUSIONS

There is a critical lack of high quality evidence for the effectiveness of most therapies for CRPS. Until further larger trials are undertaken, formulating an evidence-based approach to managing CRPS will remain difficult.

Assessing the effectiveness of 'pulse radiofrequency treatment of dorsal root ganglion' in patients with chronic lumbar radicular pain: study protocol for a randomized control trial

Background

Chronic lumbar radicular pain can be described as neuropathic pain along the distribution of a particular nerve root. The dorsal root ganglion has been implicated in its pathogenesis by giving rise to abnormal impulse generation as a result of irritation, direct compression and sensitization. Chronic lumbar radicular pain is commonly treated with medications, physiotherapy and epidural steroid injections. Epidural steroid injections are associated with several common and rarer side effects such as spinal cord infarction and death. It is essential and advantageous to look for alternate interventions which could be effective with fewer side effects.

Pulse radio frequency is a relatively new technique and is less destructive then conventional radiofrequency. Safety and effectiveness of pulse radio frequency in neuropathic pain has been demonstrated in animal and humans studies. Although its effects on dorsal root ganglion have been studied in animals there is only one randomized control trial in literature demonstrating its effectiveness in cervical radicular pain and none in lumbar radicular pain. Our primary objective is to study the feasibility of a larger trial in terms of recruitment and methodology. Secondary objectives are to compare the treatment effects and side effects.

Methods/designs

This is a single-center, parallel, placebo-controlled, triple-blinded (patients, care-givers, and outcome assessors), randomized control trial. Participants will have a history of chronic lumbar radicular pain for at least 4 months in duration. Once randomized, all patients will have an intervention involving fluoroscopy guided needle placement to appropriate dorsal root ganglion. After test stimulation in both groups; the study group will have a pulse radio frequency treatment at 42°C for 120 s to the dorsal root ganglion, with the control group having only low intensity test stimulation for the same duration. Primary outcome is to recruit at least four patients every month with 80% of eligible patients being recruited. Secondary outcomes would be to assess success of intervention through change in the visual analogue scale measured at 4 weeks post intervention and side effects. Allocation to each group will be a 1:1 ratio with allocation block sizes of 2, 4, and 6.

Trial registration

ClinicalTrials.gov NCT01117870

Meningitis after percutaneous radiofrequency trigeminal ganglion lesion. Case report and review of literature

CASE REPORT

A 79-year-old man with severe trigeminal neuralgia presented to the pain clinic, and was offered a radiofrequency trigeminal ganglion lesion. He had only partial response to the first procedure, so a second was undertaken. The following day he presented with signs of meningitis and the diagnosis was confirmed on lumbar puncture. He was treated with appropriate antibiotics, and recovered well.

LITERATURE REVIEW

The current literature on reports of meningitis after percutaneous trigeminal ganglion lesioning reveals an overall mean incidence of meningitis of 0.15% (confidence interval 0.10-0.21). The Scottish Intercollegiate Guidelines Network guide the decision on the routine use of antimicrobial prophylaxis, and although the risk of infection can be estimated from the literature and the severity of infection is high, the effectiveness and consequences of prophylaxis cannot be established.

CONCLUSION

If breach of the oral mucosa has occurred, then antibiotic prophylaxis should be administered.

Influence of radiofrequency energy delivery at the gastroesophageal junction (the Stretta procedure) on symptoms, acid exposure, and esophageal sensitivity to acid perfusion in gastroesophagal reflux disease

Several studies have demonstrated that radiofrequency energy delivery at the gastroesophageal junction (the Stretta procedure) induces symptom relief in gastroesophageal reflux disease (GERD), although improvement of acid exposure on pH monitoring was usually limited. A role for decreased esophageal sensitivity has been suggested. Our aim was to evaluate the influence of Stretta on symptoms, acid exposure, and sensitivity to esophageal acid perfusion in GERD. Thirteen patients with established proton pump inhibitor (PPI)-dependent GERD (three males; mean age, 51+/-10 years) participated in the study. Before and 6 months after the procedure symptom score, pH monitoring and Bernstein acid perfusion test were performed. The latter was done by infusing HCl (pH 0.1) at a rate of 6 ml/min 15 cm proximal to the gastroesophageal junction for a maximum of 30 min or until the patients experienced heartburn. Results were compared by Student's t-test. Stretta procedure time was 51+/-4 min and no complications occurred. After 6 months, the symptom score was significantly improved (12.5+/-2.0 to 7.5+/-2.1; P<0.05), seven patients no longer needed daily PPI, and acid exposure was significantly decreased (11.6%+/-1.6% to 8.5%+/-1.8% of time pH<4; P<0.05). The time needed to induce heartburn during acid perfusion decreased from 9.5+/-2.3 to 18.1+/-3.4 min (P=0.01), and five patients became insensitive to 30-min acid perfusion, versus none at baseline (P=0.04). In conclusion, the Stretta procedure induces subjective improvement of GERD symptoms and decreases esophageal acid exposure. In addition, esophageal acid sensitivity is decreased 6 months after the Stretta procedure. The mechanism underlying this finding and its relevance to symptom control require further studies.

Palliative radiofrequency ablation for recurrent prostate cancer

Percutaneous radiofrequency ablation (RFA) is a minimally invasive local therapy for cancer. Its efficacy is now becoming well documented in many different organs, including liver, kidney, and lung. The goal of RFA is typically complete eradication of a tumor in lieu of an invasive surgical procedure. However, RFA can also play an important role in the palliative care of cancer patients. Tumors which are surgically unresectable and incompatible for complete ablation present the opportunity for RFA to be used in a new paradigm. Cancer pain runs the gamut from minor discomfort relieved with mild pain medication to unrelenting suffering for the patient, poorly controlled by conventional means. RFA is a tool which can potentially palliate intractable cancer pain. We present here a case in which RFA provided pain relief in a patient with metastatic prostate cancer with pain uncontrolled by conventional methods.

Overall fibromyalgia pain is predicted by ratings of local pain and pain-related negative affect—possible role of peripheral tissues

OBJECTIVES

Despite variable numbers and intensities of local pain areas, fibromyalgia (FM) patients can provide overall clinical pain ratings. We hypothesized that the overall clinical pain is largely determined by the pain intensity of local body areas. Thus, we assessed the role of local body pains as predictors of overall clinical pain in FM patients.

METHODS

Ratings of overall clinical pain intensity and pain-related negative affect (PRNA) were obtained from 277 FM patients. In addition, the patients identified painful body areas by shading a body pain diagram and rated the intensity of each pain area using a mechanical visual analogue scale (VAS). Hierarchical regression analyses were used to examine predictors of overall clinical FM pain intensity including PRNA, number of local pain areas, and maximal/average intensity of local pain areas.

RESULTS

The average overall clinical pain rating of all FM patients was 4.6 (S.D. 2.3) VAS. The PRNA accounted for 19%, number of painful body areas for 9% and maximal/average local pain for 27% of the variance of overall clinical FM pain (P-values < 0.001). The combination of all factors predicted 55% of the variance in overall clinical pain intensity of FM patients.

CONCLUSION

Peripheral factors (maximal/average local pain and number of painful body areas) predicted most of the variance of overall clinical FM pain, suggesting that the input of pain by the peripheral tissues is clinically relevant. About 19% of the pain variance was predicted by PRNA. Thus, peripheral pain and negative affect appear to be particularly relevant for overall FM pain and may represent important targets for future therapies.

Craniofacial Neural Disorders: A Guide for Diagnosis and Management

The purpose of this article is to provide a succinct diagnosis and management regimen for neural disorders of the craniofacial region. This guide is an attempt to organize available data in a format for use by the craniofacial pain practitioner. The management regimens are brief because the management of many of these disorders may be outside the scope of dentistry. Also, the purpose of this guide is to be user-friendly and complete. Terminology is based on a literature review so individual disorders may be researched more completely.