Radiofrequency for chronic lumbosacral and cervical pain: Results of a consensus study using the RAND/UCLA appropriateness method.

BACKGROUND: Despite the routine use of radiofrequency (RF) for the treatment of chronic pain in the lumbosacral and cervical region, there remains uncertainty on the most appropriate patient selection criteria. This study aimed to develop appropriateness criteria for RF in relation to relevant patient characteristics, considering RF ablation (RFA) for the treatment of chronic axial pain and pulsed RF (PRF) for the treatment of chronic radicular pain. METHODS: The RAND/UCLA Appropriateness Method (RUAM) was used to explore the opinions of a multidisciplinary European panel on the appropriateness of RFA and PRF for a variety of clinical scenarios. Depending on the type of pain (axial or radicular), the expert panel rated the appropriateness of RFA and PRF for a total of 219 clinical scenarios. RESULTS: For axial pain in the lumbosacral or cervical region, appropriateness of RFA was determined by the dominant pain trigger and location of tenderness on palpation with higher appropriateness scores if these variables were suggestive of the diagnosis of facet or sacroiliac joint pain. Although the opinions on the appropriateness of PRF for lumbosacral and cervical radicular pain were fairly dispersed, there was agreement that PRF is an appropriate option for well-selected patients with radicular pain due to herniated disc or foraminal stenosis, particularly in the absence of motor deficits. The panel outcomes were embedded in an educational e-health tool that also covers the psychosocial aspects of chronic pain, providing integrated recommendations on the appropriate use of (P)RF interventions for the treatment of chronic axial and radicular pain in the lumbosacral and cervical region. CONCLUSIONS: A multidisciplinary European expert panel established patient-specific recommendations that may support the (pre)selection of patients with chronic axial and radicular pain in the lumbosacral and cervical region for either RFA or PRF (accessible via https://rftool.org). Future studies should validate these recommendations by determining their predictive value for the outcomes of (P)RF interventions.

3. Pain originating from the lumbar facet joints.

INTRODUCTION: Pain originating from the lumbar facets can be defined as pain that arises from the innervated structures comprising the joint: the subchondral bone, synovium, synovial folds, and joint capsule. Reported prevalence rates range from 4.8% to over 50% among patients with mechanical low back pain, with diagnosis heavily dependent on the criteria employed. In well-designed studies, the prevalence is generally between 10% and 20%, increasing with age. METHODS: The literature on the diagnosis and treatment of lumbar facet joint pain was retrieved and summarized. RESULTS: There are no pathognomic signs or symptoms of pain originating from the lumbar facet joints. The most common reported symptom is uni- or bilateral (in more advanced cases) axial low back pain, which often radiates into the upper legs in a non-dermatomal distribution. Most patients report an aching type of pain exacerbated by activity, sometimes with morning stiffness. The diagnostic value of abnormal radiologic findings is poor owing to the low specificity. SPECT can accurately identify joint inflammation and has a predictive value for diagnostic lumbar facet injections. After "red flags" are ruled out, conservatives should be considered. In those unresponsive to conservative therapy with symptoms and physical examination suggesting lumbar facet joint pain, a diagnostic/prognostic medial branch block can be performed which remains the most reliable way to select patients for radiofrequency ablation. CONCLUSIONS: Well-selected individuals with chronic low back originating from the facet joints may benefit from lumbar medial branch radiofrequency ablation.

5. Sacroiliac joint pain.

INTRODUCTION: Sacroiliac (SI) joint pain is defined as pain localized in the anatomical region of the SI joint. The reported prevalence of SI joint pain among patients with mechanical low back pain varies between 15% and 30%. METHODS: In this narrative review, the literature on the diagnosis and treatment of SI joint pain was updated and summarized. RESULTS: Patient's history provides clues on the source of pain. The specificity and sensitivity of provocative maneuvers are relatively high when three or more tests are positive, though recent studies have questioned the predictive value of single or even batteries of provocative tests. Medical imaging is indicated only to rule out red flags for potentially serious conditions. The diagnostic value of SI joint infiltration with local anesthetic remains controversial due to the potential for false-positive and false-negative results. Treatment of SI joint pain ideally consists of a multidisciplinary approach that includes conservative measures as first-line therapies (eg, pharmacological treatment, cognitive-behavioral therapy, manual medicine, exercise therapy and rehabilitation treatment, and if necessary, psychological support). Intra- and extra-articular corticosteroid injections have been documented to produce pain relief for over 3 months in some people. Radiofrequency ablation (RFA) of the L5 dorsal ramus and S1-3 (or 4) lateral branches has been shown to be efficacious in numerous studies, with extensive lesioning strategies (eg, cooled RFA) demonstrating the strongest evidence. The reported rate of complications for SI joint treatments is low. CONCLUSIONS: SI joint pain should ideally be managed in a multidisciplinary and multimodal manner. When conservative treatment fails, corticosteroid injections and radiofrequency treatment can be considered.

Radiofrequency Ablation for the Management of Pain of Spinal Origin in Orthopedics.

Radiofrequency (RF) is a minimally invasive procedure for interrupting or modifying nociceptive pathways to manage musculoskeletal neuropathic and nociplastic pain. RF has been used to manage cervical and lumbar facet joint syndromes. The benefits of RF are the following: it is safer than surgery; it doesn´t need general anesthesia, by that means diminishing the complications; it causes pain alleviation for a minimum of 3-4 months; it can be repeated if needed; it improves joint function; and it minimizes the necessity for oral pain treatment. RF must not be used in pregnant women; unstable joints, uncontrolled diabetes mellitus; and presence of an implanted defibrillator. Even though complications from RF are rare, possible adverse events are infection, hemorrhage, numbness or dysesthesia, greater pain in the procedure area, and differentiation impact. Even though there is a peril of injuring non-targeted neural tissue and other tissues, this can be lessened by carrying out the procedure with the help of fluoroscopy, ultrasonography or computed tomography. RF seems to be a helpful procedure for relieving chronic pain syndromes; despite this, definite proof of the procedure's effectiveness is still needed. RF is an encouraging procedure for treating chronic spinal pain, especially when other procedures are pointless or not feasible.

Upper limb and lower limb radiofrequency treatments in orthopaedics.

Radiofrequency (RF) is a minimally invasive technique for disrupting or altering nociceptive pathways to treat musculoskeletal neuropathic and nociplastic pain. RF has been employed to treat painful shoulder, lateral epicondylitis, knee and hip osteoarthritis, chronic knee pain, Perthes disease, greater trochanteric pain syndrome, plantar fasciitis, and painful stump neuromas; it has also been employed before and after painful total knee arthroplasty and after anterior cruciate ligament reconstruction. The benefits of RF include the following:it is safer than surgery; there is no need for general anaesthesia, thereby reducing adverse effects; it alleviates pain for a minimum of 3-4 months; it can be repeatable if necessary; and it improves joint function and minimizes the need for oral pain medication. RF is contraindicated for pregnant women; unstable joints (hip, knee, and shoulder); uncontrolled diabetes mellitus; presence of an implanted defibrillator; and chronic joint infection (hip, knee, and shoulder). Although adverse events from RF are unusual, potential complications can include infection, bleeding, numbness or dysesthesia, increased pain at the procedural site, deafferentation effect, and Charcot joint neuropathy. Although there is a risk of damaging non-targeted neural tissue and other structures, this can be mitigated by performing the technique under imaging guidance (fluoroscopy, ultrasonography, and computed tomography). RF appears to be a valuable technique for alleviating chronic pain syndromes; however, firm proof of the technique's efficacy is still required. RF is a promising technique for managing chronic musculoskeletal of the limbs pain, particularly when other techniques are futile or not possible.

The Use of Contrast Agents in Interventional Pain Procedures: A Multispecialty and Multisociety Practice Advisory on Nephrogenic Systemic Fibrosis, Gadolinium Deposition in the Brain, Encephalopathy After Unintentional Intrathecal Gadolinium Injection, and Hypersensitivity Reactions.

This Practice Advisory presents a comprehensive and evidence-based set of position statements and recommendations for the use of contrast media in interventional pain procedures. The advisory was established by an international panel of experts under the auspices of 11 multinational and multispecialty organizations based on a comprehensive review of the literature up to December 31, 2019. The advisory discusses the risks of using gadolinium-based contrast agents. These include nephrogenic systemic fibrosis, gadolinium brain deposition/retention, and encephalopathy and death after an unintentional intrathecal gadolinium injection. The advisory provides recommendations on the selection of a specific gadolinium-based contrast agent in patients with renal insufficiency, those who had multiple gadolinium-enhanced magnetic resonance imaging examinations, and in cases of paraspinal injections. Additionally, recommendations are made for patients who have a history of mild, moderate, or severe hypersensitivity reactions to contrast medium.

Randomized Pragmatic Pilot Trial Comparing Perpendicular Thin Electrode Versus Parallel Thick Electrode Approaches for Lumbar Medial Branch Neurotomy in Facetogenic Low Back Pain.

OBJECTIVES: Although there are different ways of performing medial branch neurotomy on facetogenic low back pain, few studies have compared clinical outcomes of a parallel technique over the medial branch vs. a perpendicular technique. We investigated differences in pain outcome with both techniques. DESIGN: This was a prospective, pilot, randomized, pragmatic trial (double blinded in the diagnostic phase). SETTING: A comparative pilot trial was conducted at an academic pain center. METHODS: Patients who did not respond to conservative medications and had severe lumbar pain for more than 3 months (VAS score ≥ 65) were included. A double diagnostic block with local anesthetic and placebo was performed, double blinded. Patients who had 80% relief from the local anesthetic and no substantial relief from placebo were randomized to undergo medial branch neurotomy under fluoroscopy, placing an electrode parallel or perpendicular to the medial branch. The primary outcome was differences in the VAS score at 1, 3, and 6 months. The secondary outcomes were Oswestry Disability Index score, Roland Morris Questionnaire score, and other functional Likert scale scores. RESULTS: Forty-three consecutive patients were randomized to parallel (n = 20) or perpendicular (n = 23) neurotomy. There were no significant differences in VAS, Oswestry Disability Index, or Roland Morris Questionnaire scores at 1, 3, or 6 months between groups. Statistically significant differences were found in the categorical analysis at 6 months in the evolution of pain, Oswestry Disability Index score, Roland Morris Questionnaire score, and some Likert scale scores in favor of the parallel group. CONCLUSIONS: There were differences at 6 months in the categorical analysis of the evolution of pain, Oswestry Disability Index score, Roland Morris Questionnaire score, and some functional Likert scale scores, all in favor of the parallel group.

The appropriate management of persisting pain after spine surgery: a European panel study with recommendations based on the RAND/UCLA method.

PURPOSE: Management of patients with persisting pain after spine surgery (PPSS) shows significant variability, and there is limited evidence from clinical studies to support treatment choice in daily practice. This study aimed to develop patient-specific recommendations on the management of PPSS. METHODS: Using the RAND/UCLA appropriateness method (RUAM), an international panel of 6 neurosurgeons, 6 pain specialists, and 6 orthopaedic surgeons assessed the appropriateness of 4 treatment options (conservative, minimally invasive, neurostimulation, and re-operation) for 210 clinical scenarios. These scenarios were unique combinations of patient characteristics considered relevant to treatment choice. Appropriateness had to be expressed on a 9-point scale (1 = extremely inappropriate, 9 = extremely appropriate). A treatment was considered appropriate if the median score was ≥ 7 in the absence of disagreement (≥ 1/3 of ratings in each of the opposite sections 1-3 and 7-9). RESULTS: Appropriateness outcomes showed clear and specific patterns. In 48% of the scenarios, exclusively one of the 4 treatments was appropriate. Conservative treatment was usually considered appropriate for patients without clear anatomic abnormalities and for those with new pain differing from the original symptoms. Neurostimulation was considered appropriate in the case of (predominant) neuropathic leg pain in the absence of conditions that may require surgical intervention. Re-operation could be considered for patients with recurrent disc, spinal/foraminal stenosis, or spinal instability. CONCLUSIONS: Using the RUAM, an international multidisciplinary panel established criteria for appropriate treatment choice in patients with PPSS. These may be helpful to educate physicians and to improve consistency and quality of care. These slides can be retrieved under Electronic Supplementary Material.

Changes in Quality of Life after 3 months of Usual Care in a Large Sample of Patients with Noncancer Pain: The "QOOL: Quality of Life and Pain" Study.

Large-scale observational studies can provide useful information on changes in health outcomes over time. The aim of this study was to investigate the effect of 3 months of usual care on quality of life (QOL) and pain outcomes in noncancer chronic pain patients managed by pain specialists and to examine factors associated with changes in QOL. This was assessed using the EQ-5D and pain outcomes using the Brief Pain Inventory (BPI). Changes in QOL and pain were studied for the overall sample and in subgroups defined by baseline pain severity. Multivariate regression was used to investigate factors associated with change on EQ-5D. Three thousand and twenty-nine patients were included for analysis. After 3 months of usual care, a mean of 40.9% of patients showed improvement on individual EQ-5D dimensions, with the highest rates of improvement seen on the pain/discomfort (50.8%) and anxiety/depression (48.3%) dimensions. The EQ-5D Index increased from a mean (SD) of 0.35 (0.2) to 0.58 (0.21) points between baseline and month 3, and the thermometer from 41.5 (19.4) to 58.7 (17.8), indicating a large effect. Improvements in QOL were larger in those with severe baseline pain. The BPI severity summary score improved from a mean (SD) of 6.5 (1.4) to 4.1 (1.7) and the interference summary score from 6.6 (1.5) to 4.2 (1.9). Changes on the BPI severity and interference scores were associated with changes in the EQ-5D Index and thermometer. In conclusion, 3 months of usual care in noncancer pain patients led to substantial improvements in QOL and pain outcomes.

Validation of the Short Form of the Brief Pain Inventory (BPI-SF) in Spanish Patients with Non-Cancer-Related Pain.

The Brief Pain Inventory (BPI) is a widely used pain measurement tool. There are 2 versions, the BPI Long Form (BPI-LF) and Short Form (BPI-SF), which share 2 core scales measuring pain severity and pain interference but which use different recall periods (24 hours vs. 1 week). To date, the BPI-SF has not been validated for use in Spain. This study investigated the psychometric properties of the BPI-SF Spanish version and compared results on the core scales between BPI-LF and BPI-SF. The data came from a 3-month observational study of 3,029 nononcologic patients managed in Spanish pain units. The BPI-SF's reliability, validity, and responsiveness were assessed. The effect of different recall periods was investigated by using intraclass correlation coefficients (ICCs) to determine the strength of correlation between BPI-LF and BPI-SF. The BPI-SF showed good reliability, with Cronbach's alphas of 0.931 for the severity and interference scales, which also discriminated well between patients reporting different levels of quality of life on EuroQol-5D dimensions (between group effect sizes [ESs] over 0.8). Substantial improvements were seen on both subscales after 3 months of treatment (ES of 1.76 for pain severity and 1.51 for pain interference). Recall period did not noticeably affect scores; ICCs (95% CI) between the long and short versions were 0.946 (0.938 to 0.954) and 0.929 (0.919 to 0.939) for the severity and interference subscales, respectively. The Spanish version of the BPI-SF is a valid and reliable instrument to measure pain severity and interference.

Transcranial direct current stimulation effects on I-wave activity in humans.

Transcranial direct current stimulation (tDCS) of the human cerebral cortex modulates cortical excitability noninvasively in a polarity-specific manner: anodal tDCS leads to lasting facilitation and cathodal tDCS to inhibition of motor cortex excitability. To further elucidate the underlying physiological mechanisms, we recorded corticospinal volleys evoked by single-pulse transcranial magnetic stimulation of the primary motor cortex before and after a 5-min period of anodal or cathodal tDCS in eight conscious patients who had electrodes implanted in the cervical epidural space for the control of pain. The effects of anodal tDCS were evaluated in six subjects and the effects of cathodal tDCS in five subjects. Three subjects were studied with both polarities. Anodal tDCS increased the excitability of cortical circuits generating I waves in the corticospinal system, including the earliest wave (I1 wave), whereas cathodal tDCS suppressed later I waves. The motor evoked potential (MEP) amplitude changes immediately following tDCS periods were in agreement with the effects produced on intracortical circuitry. The results deliver additional evidence that tDCS changes the excitability of cortical neurons.