The Diagnostic Value of an X-ray-based Scoring System for Degeneration of the Cervical Spine: A Reproducibility and Validation Study.

BACKGROUND: In interventional pain medicine, cervical facet joint (CFJ) pain is commonly treated with CFJ denervation techniques, almost automatically assuming degeneration of the CFJs as an important cause of CFJ pain. A standard cervical X-ray is still commonly used in the clinical evaluation of patients suspected for CFJ degeneration. Although degenerative features can be visualized by different radiological imaging techniques, the relation between radiological degenerative features of the cervical spine and pain remains controversial. Paramount in order to estimate the clinical usefulness of a radiological imaging is to establish the reproducibility of the radiological scoring system. A reproducible and clinically feasible diagnostic scoring system was developed to estimate cervical degeneration on standard cervical X-rays. MATERIALS AND METHODS: A reproducibility study for the interpretation of degenerative abnormalities on standard cervical X-rays was performed, using a dichotomous outcome (degenerative abnormalities present Yes/No). The estimation of intervertebral disc height loss on standard cervical X-rays was validated with computed tomography (CT) scan measurements. RESULTS: Five radiological degenerative features on standard cervical X-rays (disc height loss, anterior vertebral osteophytes, posterior vertebral osteophytes, vertebral end plate sclerosis, and uncovertebral osteoarthritis) showed a substantial to excellent reproducibility (kappa value ≥ 0.60). The qualitative definition of disc height loss used in the reproducibility study showed a substantial agreement with the actual measurements of disc height loss on CT scan (kappa value = 0.69). CONCLUSION: Subjective judgment of a cervical standard X-ray is a reproducible method to demonstrate degenerative abnormalities of the cervical spine.

"Evidence-Based Interventional Pain Medicine According to Clinical Diagnoses": Update 2018.

INTRODUCTION: Between 2009 and 2011 a series of 26 articles on evidence-based medicine for interventional pain medicine according to clinical diagnoses were published. The high number of publications since the last literature search justified an update. METHODS: For the update an independent 3rd party, specialized in systematic reviews was asked in 2015 to perform the literature search and summarize relevant evidence using Cochrane and GRADE methodology to compile guidelines on interventional pain management. The guideline committee reviewed the information and made a last update on March 1st 2018. The information from new studies published after the research performed by the 3th party and additional observational studies was used to incorporate other factors such as side effects and complications, invasiveness, costs and ethical factors, which influence the ultimate recommendations. RESULTS: For the different indications a total of 113 interventions were evaluated. Twenty-seven (24%) interventions were new compared to the previous guidelines and the recommendation changed for only 3 (2.6%) of the interventions. DISCUSSION: This article summarizes the evolution of the quality of evidence and the strength of recommendations for the interventional pain treatment options for 28 clinical pain diagnoses.

Safe Use of Epidural Corticosteroid Injections: Recommendations of the WIP Benelux Work Group.

BACKGROUND: Epidural corticosteroid injections are used frequently worldwide in the treatment of radicular pain. Concerns have arisen involving rare major neurologic injuries after this treatment. Recommendations to prevent these complications have been published, but local implementation is not always feasible due to local circumstances, necessitating local recommendations based on literature review. METHODS: A work group of 4 stakeholder pain societies in Belgium, The Netherlands, and Luxembourg (Benelux) has reviewed the literature involving neurological complications after epidural corticosteroid injections and possible safety measures to prevent these major neurologic injuries. RESULTS: Twenty-six considerations and recommendations were selected by the work group. These involve the use of imaging, injection equipment particulate and nonparticulate corticosteroids, epidural approach, and maximal volume to be injected. CONCLUSION: Raising awareness about possible neurological complications and adoption of safety measures recommended by the work group aim at reducing the risks for these devastating events.

No Transfer of Pressure to Adjacent Discs During Human Low-Pressure Controlled Discography: A Prospective Clinical Study.

Background: A substantial part of low back pain (LBP) originates from degeneration of the intervertebral disc. To confirm the diagnosis of discogenic pain, provocation discography seems the best available tool. However, provocation discography is also considered to be a controversial and subjective test because the patient's personal pain response is the most crucial for the result of the test. Recently, an in vivo porcine study and a study in nine human subjects showed passing of pressure to the adjacent discs during discography. This could mean that the concordant pain the patient describes originates from an adjacent disc. The object of this study is to assess if during human lumbar pressure-controlled provocation discography there is pressure transmission to adjacent discs. Methods: Consecutive patients between age 18 and 65 years with intractable low back pain and at least 50% preserved height of the suspected painful disc were included. Exclusion criteria were prior lumbar surgery of the suspected level, use of anticoagulants, pregnancy, local infection, and iodine allergy. An arterial blood pressure monitoring system simultaneously assessed the pressure in the adjacent discs while low-speed flow, pressure-controlled discography was performed. Results: In 50 patients with a positive discography, the average intradiscal peak pressure was 15.1 psi (SD = 11.1). In 48 procedures, no pressure rise in the adjacent discs was found. A small pressure rise (1.1 psi) in the adjacent disc during discography was recorded in two patients. Conclusions: Pressure rise in adjacent discs does not seem to occur during low-speed flow pressure-controlled lumbar provocation discography. False-positive pain reactions caused by potentially painful adjacent discs are therefore unlikely during pressure-controlled discography.

Optical signature of nerve tissue-Exploratory ex vivo study comparing optical, histological, and molecular characteristics of different adipose and nerve tissues.

BACKGROUND: During several anesthesiological procedures, needles are inserted through the skin of a patient to target nerves. In most cases, the needle traverses several tissues-skin, subcutaneous adipose tissue, muscles, nerves, and blood vessels-to reach the target nerve. A clear identification of the target nerve can improve the success of the nerve block and reduce the rate of complications. This may be accomplished with diffuse reflectance spectroscopy (DRS) which can provide a quantitative measure of the tissue composition. The goal of the current study was to further explore the morphological, biological, chemical, and optical characteristics of the tissues encountered during needle insertion to improve future DRS classification algorithms. METHODS: To compare characteristics of nerve tissue (sciatic nerve) and adipose tissues, the following techniques were used: histology, DRS, absorption spectrophotometry, high-resolution magic-angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy, and solution 2D 13 C-1 H heteronuclear single-quantum coherence spectroscopy. Tissues from five human freshly frozen cadavers were examined. RESULTS: Histology clearly highlights a higher density of cellular nuclei, collagen, and cytoplasm in fascicular nerve tissue (IFAS). IFAS showed lower absorption of light around 1200 nm and 1750 nm, higher absorption around 1500 nm and 2000 nm, and a shift in the peak observed around 1000 nm. DRS measurements showed a higher water percentage and collagen concentration in IFAS and a lower fat percentage compared to all other tissues. The scattering parameter (b) was highest in IFAS. The HR-MAS NMR data showed three extra chemical peak shifts in IFAS tissue. CONCLUSION: Collagen, water, and cellular nuclei concentration are clearly different between nerve fascicular tissue and other adipose tissue and explain some of the differences observed in the optical absorption, DRS, and HR-NMR spectra of these tissues. Some differences observed between fascicular nerve tissue and adipose tissues cannot yet be explained but may be helpful in improving the discriminatory capabilities of DRS in anesthesiology procedures. Lasers Surg. Med. 50:948-960, 2018. © 2018 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.

Long-Term Spinal Cord Stimulation Alleviates Mechanical Hypersensitivity and Increases Peripheral Cutaneous Blood Perfusion in Experimental Painful Diabetic Polyneuropathy.

OBJECTIVES: This study utilizes a model of long-term spinal cord stimulation (SCS) in experimental painful diabetic polyneuropathy (PDPN) to investigate the behavioral response during and after four weeks of SCS (12 hours/day). Second, we investigated the effect of long-term SCS on peripheral cutaneous blood perfusion in experimental PDPN. METHODS: Mechanical sensitivity was assessed in streptozotocin induced diabetic rats (n = 50) with von Frey analysis. Hypersensitive rats (n = 24) were implanted with an internal SCS battery, coupled to an SCS electrode covering spinal levels L2-L5. The effects of four weeks of daily conventional SCS for 12 hours (n = 12) or Sham SCS (n = 12) were evaluated with von Frey assessment, and laser Doppler imaging (LDI). RESULTS: Average paw withdrawal thresholds (PWT) increased during long-term SCS in the SCS group, in contrast to a decrease in the Sham group (Sham vs. SCS; p = 0.029). Twenty-four hours after long-term SCS average PWT remained higher in the SCS group. Furthermore, the SCS group showed a higher cutaneous blood perfusion during long-term SCS compared to the Sham group (Sham vs. SCS; p = 0.048). Forty-eight hours after long-term SCS, no differences in skin perfusion were observed. DISCUSSION: We demonstrated that long-term SCS results in decreased baseline mechanical hypersensitivity and results in increased peripheral blood perfusion during stimulation in a rat model of PDPN. Together, these findings indicate that long-term SCS results in modulation of the physiological circuitry related to the nociceptive system in addition to symptomatic treatment of painful symptoms.

Patient expectations for management of chronic non-cancer pain: A systematic review.

BACKGROUND: Chronic pain is a major economic and social health problem. Up to 79% of chronic pain patients are unsatisfied with their pain management. Meeting patients' expectations is likely to produce greater satisfaction with care. The challenge is to explore patients' genuine expectations and needs. However, the term expectation encompasses several concepts and may concern different aspects of health-care provision. OBJECTIVE: This review aimed to systematically collect information on types and subject of patients' expectations for chronic pain management. SEARCH STRATEGY: We searched for quantitative and qualitative studies. Because of the multidimensional character of the term "expectations," the search included subject headings and free text words related to the concept of expectations. DATA EXTRACTION AND SYNTHESIS: A framework for understanding patients' expectations was used to map types of expectations within structure, process or outcome of health care. MAIN RESULTS: Twenty-three research papers met the inclusion criteria: 18 quantitative and five qualitative. This review found that assessment of patients' expectations for treatment is mostly limited to outcome expectations (all 18 quantitative papers and four qualitative papers). Patients generally have high expectations regarding pain reduction after treatment, but expectations were higher when expressed as an ideal expectation (81-93% relief) than as a predicted expectation (44-64%). DISCUSSION AND CONCLUSIONS: For health-care providers, for pain management and for pain research purposes, the awareness that patients express different types of expectations is important. For shared decision making in clinical practice, it is important that predicted expectations of the patient are known to the treating physician and discussed. Structure and process expectations are under-represented in our findings. However, exploring and meeting patients' expectations regarding structure, process and outcome aspects of pain management may increase patient satisfaction.

Co-creative development of an eHealth nursing intervention: Self-management support for outpatients with cancer pain.

INTRODUCTION: Co-creative methods, having an iterative character and including different perspectives, allow for the development of complex nursing interventions. Information about the development process is essential in providing justification for the ultimate intervention and crucial in interpreting the outcomes of subsequent evaluations. This paper describes a co-creative method directed towards the development of an eHealth intervention delivered by registered nurses to support self-management in outpatients with cancer pain. METHODS: Intervention development was divided into three consecutive phases (exploration of context, specification of content, organisation of care). In each phase, researchers and technicians addressed five iterative steps: research, ideas, prototyping, evaluation, and documentation. Health professionals and patients were consulted during research and evaluation steps. RESULTS: Collaboration of researchers, health professionals, patients and technicians was positive and valuable in optimising outcomes. The intervention includes a mobile application for patients and a web application for nurses. Patients are requested to monitor pain, adverse effects and medication intake, while being provided with graphical feedback, education and contact possibilities. Nurses monitor data, advise patients, and collaborate with the treating physician. CONCLUSION: Integration of patient self-management and professional care by means of eHealth key into well-known barriers and seem promising in improving cancer pain follow-up. Nurses are able to make substantial contributions because of their expertise, focus on daily living, and their bridging function between patients and health professionals in different care settings. Insights from the intervention development as well as the intervention content give thought for applications in different patients and care settings.

Boundaries of the thoracic paravertebral space: potential risks and benefits of the thoracic paravertebral block from an anatomical perspective.

PURPOSE: Thoracic paravertebral block (TPVB) may be an alternative to thoracic epidural analgesia. A detailed knowledge of the anatomy of the TPV-space (TPVS), content and adnexa is essential in understanding the clinical consequences of TPVB. The exploration of the posterior TPVS accessibility in this study allows (1) determination of the anatomical boundaries, content and adnexa, (2) description of an ultrasound-guided spread of low and high viscous liquid. METHODS: In two formalin-fixed specimens, stratification of the several layers and the 3D-architecture of the TPVS were dissected, observed and photographed. In a third unembalmed specimen, ultrasound-guided posterolateral injections at several levels of the TPVS were performed with different fluids. RESULTS: TPVS communicated with all surrounding spaces including the segmental dorsal intercostal compartments (SDICs) and the prevertebral space. TPVS transitions to the SDICs were wide, whereas the SDICs showed narrowed transitions to the lateral intercostal spaces at the costal angle. Internal subdivision of the TPVS in a subendothoracic and an extra-pleural compartment by the endothoracic fascia was not observed. Caudally injected fluids spread posteriorly to the costodiaphragmatic recess, showing segmental intercostal and slight prevertebral spread. CONCLUSIONS: Our detailed anatomical study shows that TPVS is a potential space continuous with the SDICs. The separation of the TPVS in a subendothoracic and an extra-pleural compartment by the endothoracic fascia was not observed. Based on the ultrasound-guided liquid spread we conclude that the use of a more lateral approach might increase the probability of intravascular puncture or catheter position.

A Modified Posterolateral Approach for Radiofrequency Denervation of the Medial Branch of the Cervical Segmental Nerve in Cervical Facet Joint Pain Based on Anatomical Considerations.

The cervical facet joints, also called the zygapophyseal joints, are a potential source of neck pain (cervical facet joint pain). The cervical facet joints are innervated by the cervical medial branches (CMBs) of the cervical segmental nerves. Cervical facet joint pain has been shown to respond to multisegmental radiofrequency denervation of the cervical medial branches. This procedure is performed under fluoroscopic guidance. Currently, three approaches are described and used. Those three techniques of radiofrequency treatment of the CMBs, classified on the base of the needle trajectory toward the anatomical planes, are as follows: the posterolateral technique, the posterior technique, and the lateral technique. We describe the three techniques with their advantages and disadvantages. Anatomical studies providing a topographic anatomy of the course of the CMBs are reviewed. We developed a novel approach based on the observed strengths and weaknesses of the three currently used approaches and based on recent anatomical findings. With this fluoroscopic-guided approach, there is always bone (the facet column) in front of the needle, which makes it safer, and the insertion point is easier to determine without the risk of positioning the radiofrequency needle too dorsally.

Predictive Factors for Successful Outcome of Pulsed Radiofrequency Treatment in Patients with Intractable Lumbosacral Radicular Pain.

BACKGROUND: In a previous prospective study on pulsed radiofrequency (PRF) treatment adjacent to the lumbar dorsal root ganglion (DRG) for patients with chronic lumbosacral radicular pain, we reported success in 55.4% of the patients at 6 months. Identification of predictors for success after PRF may improve outcome. We assessed the predictors of PRF in patients with chronic intractable lumbosacral radicular pain. METHODS: Patients with monosegmental chronic lumbosacral radicular pain of L5 or S1 first received a selective nerve root block at the corresponding level. Independent of the result of this block a PRF treatment at the same level was performed. At 6 weeks, 3 months, and 6 months after the procedure the outcome was evaluated. RESULTS: A positive diagnostic nerve root block and age ≥ 55 were predictive factors for successful outcome at 6 months, while disability was a negative predictor.The use of failed back surgery syndrome, gender, duration of pain, Numerical Rating Scale, level and side of treatment, DN4, and RAND-36 as predictors for success was not supported. CONCLUSIONS: Successful outcome after PRF adjacent to the DRG, in patients with intractable chronic lumbosacral radicular pain, is more likely in patients ≥ 55 years, with limited disability and after a positive diagnostic nerve root block. A combination of all these factors creates a fair predictive value (AUC: 0.73).

First Dutch Consensus of Pain Quality Indicators for Pain Treatment Facilities.

BACKGROUND: There is a general consensus about the need to define and improve the quality of pain treatment facilities. Although guidelines and recommendations to improve the quality of pain practice management have been launched, provision of appropriate pain treatment is inconsistent and the quality of facilities varies widely. The aim of the study was to develop an expert-agreed list of quality indicators applicable to pain treatment facilities. The list was also intended to be used as the basis for a set of criteria for registered status of pain treatment facilities. METHODS: The University Pain Center Maastricht at the Department of Anesthesiology and Pain Management of the Maastricht University Medical Center conducted a 3-round Delphi study in collaboration with the Board of the Pain Section of the Dutch Society of Anesthesiologists (NVA). RESULTS: Twenty-five quality indicators were selected as relevant to 2 types of pain treatment facilities, pain clinics and pain centers. The final expert-agreed list consisted of 22 quality indicators covering 7 quality domains: supervision, availability of care, staffing level and patient load, quality policy, multidisciplinarity, regionalization, and research and education. CONCLUSIONS: This set of quality indicators may facilitate organizational evaluation and improve insight into service quality from the perspectives of patients, pain specialists, and other healthcare professionals. Recommendations for improvements to the current set of quality indicators are made. In 2014 the process of registering pain treatment facilities in the Netherlands started; facilities can register as a pain clinic or pain center.

Efficacy, Safety, and Predictors of Intradiscal Methylene Blue Injection for Discogenic Low Back Pain: Results of a Multicenter Prospective Clinical Series.

STUDY DESIGN: Prospective clinical study of intradiscal methylene blue injection for the treatment of lumbar discogenic pain. OBJECTIVE: The objective of this study was to collect information about efficacy, safety, and acceptability of the intervention, gain and burden of outcome measures, and sample size assumptions for a potential following randomized controlled trial (RCT). If the pilot study demonstrates that this treatment is potentially effective and safe, and the methods and procedures used in this study are feasible, a RCT follows. SUMMARY OF BACKGROUND DATA: Low back pain (LBP) is a highly common problem with a lifetime prevalence of more than 70%. A substantial part of chronic LBP is attributable to degenerative changes in the intervertebral disc. A recently published RCT assessing the treatment intradiscal injection of methylene blue for chronic discogenic LBP, showed exceptionally good results. METHODS: Patients were selected on clinical criteria, magnetic resonance imaging, and a positive provocative discogram. The primary outcome measure was mean pain reduction at 6 months. RESULTS: Fifteen consecutive patients with chronic lumbar discogenic pain enrolled in a multicenter prospective case series in two interventional pain treatment centers in the Netherlands. Six months after the intervention, 40% of the patients claimed at least 30% pain relief. In patients who responded, physical function improved and medication use diminished. We observed no procedural complications or adverse events. Predictors for success were Pfirrmann grading of 2 or less and higher quality of life mental component scores. CONCLUSIONS: Our findings of 40% positive respondents, and no complications, give reason to set up a randomized, double-blind, placebo-controlled, trial.

Self-management support intervention to control cancer pain in the outpatient setting: a randomized controlled trial study protocol.

BACKGROUND: Pain is a prevalent and distressing symptom in patients with cancer, having an enormous impact on functioning and quality of life. Fragmentation of care, inadequate pain communication, and reluctance towards pain medication contribute to difficulties in optimizing outcomes. Integration of patient self-management and professional care by means of healthcare technology provides new opportunities in the outpatient setting. METHODS/DESIGN: This study protocol outlines a two-armed multicenter randomized controlled trial that compares a technology based multicomponent self-management support intervention with care as usual and includes an effect, economic and process evaluation. Patients will be recruited consecutively via the outpatient oncology clinics and inpatient oncology wards of one academic hospital and one regional hospital in the south of the Netherlands. Irrespective of the stage of disease, patients are eligible when they are diagnosed with cancer and have uncontrolled moderate to severe cancer (treatment) related pain defined as NRS≥4 for more than two weeks. Randomization (1:1) will assign patients to either the intervention or control group; patients in the intervention group receive self-management support and patients in the control group receive care as usual. The intervention will be delivered by registered nurses specialized in pain and palliative care. Important components include monitoring of pain, adverse effects and medication as well as graphical feedback, education, and nurse support. Effect measurements for both groups will be carried out with questionnaires at baseline (T0), after 4 weeks (T1) and after 12 weeks (T2). Pain intensity and quality of life are the primary outcomes. Secondary outcomes include self-efficacy, knowledge, anxiety, depression and pain medication use. The final questionnaire contains also questions for the economic evaluation that includes both cost-effectiveness and cost-utility analysis. Data for the process evaluation will be gathered continuously over the study period and focus on recruitment, reach, dose delivered and dose received. DISCUSSION: The proposed study will provide insight into the effectiveness of the self-management support intervention delivered by nurses to outpatients with uncontrolled cancer pain. Study findings will be used to empower patients and health professionals to improve cancer pain control. TRIAL REGISTRATION: NCT02333968 December 29, 2014.

Pulsed radiofrequency for chronic intractable lumbosacral radicular pain: a six-month cohort study.

BACKGROUND AND OBJECTIVES: There is little evidence concerning the medical management of lumbosacral radicular pain. The prognosis for patients suffering pain for more than 3 months is poor. Pulsed radiofrequency (PRF) treatment of the dorsal root ganglion (DRG) has been suggested as a minimally invasive treatment. We studied the effect on pain and quality of life of PRF treatment of the DRG in patients with chronic, severe lumbosacral radicular pain. METHODS: Patients with lumbosacral radicular pain were screened to select a homogeneous population. PRF treatment of the DRG was performed at L5 or S1. Evaluation was carried out at 6 weeks, 3 months, and 6 months. Pain reduction and "fully recovered" or "much improvement," in terms of the global perceived effect, were the primary outcomes. Quality of life (RAND-36), disability (Oswestry Disability Index), and the neuropathic pain scales leeds assessment of neuropathic symptoms and signs (LANSS) and DN4 were registered at each time point. Medication use was scored with the Medication Quantification Scale. RESULTS: Out of 461 screened patients, 65 were included. According to the intention to treat analysis, clinical success was achieved in 56.9%, 52.3%, and 55.4% of the patients at respectively 6 weeks, 3 months, and 6 months. DN4, Oswestry Disability Index and physical component for the RAND-36 quality of life improved significantly while the mental component remained unchanged. The number of patients on opioids was reduced. CONCLUSIONS: PRF treatment of the DRG may be considered for patients with chronic, severe lumbosacral radicular pain refractory to conventional medical management.

Increased contact heat evoked potential stimulation latencies in responders to spinal cord stimulation for painful diabetic polyneuropathy.

OBJECTIVES: To analyze sensory characteristics and small nerve fiber function in patients suffering from painful diabetic polyneuropathy (PDP) and compare outcomes in responders and nonresponders to SCS treatment. METHODS: Fifteen patients with intractable PDP in the legs were recruited. If trial stimulation resulted in clinically relevant pain relief, a pulse generator was implanted and pain scores were measured after 12 months. Sensory characteristics (modified Inflammatory Neuropathy Cause and Treatment [md-INCAT] sum score) and small nerve fiber function (contact heat evoked potentials, CHEPs) were measured before implantation (D1), and CHEP measurement was repeated after two weeks of trial stimulation (D2). Outcomes in responders (N = 10) and nonresponders (N = 5) to SCS treatment were compared. Data were analyzed using nonparametric statistics. RESULTS: At one year, clinically relevant pain relief was achieved in 10 out of 15 patients. The md-INCAT score did not differ between SCS responders and nonresponders (8.0 vs. 5.0; p = 0.59). No differences were found in CHEP outcomes at D1 vs. D2, except for dorsal forearm P2 latency, and the correlation between D1 and D2 CHEP outcomes was high. Volar N2 forearm latency (0.492 vs. 0.434; p < 0.01), dorsal forearm N2 latency (0.518 vs. 0.453; p = 0.04), and dorsal forearm P2 latency (0.660 vs. 0.589; p = 0.04) were increased in SCS responders as compared with SCS nonresponders. CONCLUSIONS: From this small-scale clinical pilot study we conclude that forearm CHEP latencies are increased in PDP patients who respond to SCS therapy as compared with SCS nonresponders. Before the CHEP latency can be used as a predictor of SCS outcome in PDP patients, a large-scale study is needed.

Can we "predict" long-term outcome for ambulatory transcutaneous electrical nerve stimulation in patients with chronic pain?

BACKGROUND: Evidence for effectiveness of transcutaneous electrical nerve stimulation (TENS) is still inconclusive. As heterogeneity of chronic pain patients might be an important factor for this lack of efficacy, identifying factors for a successful long-term outcome is of great importance. METHODS: A prospective study was performed to identify variables with potential predictive value for 2 outcome measures on long term (6 months); (1) continuation of TENS, and (2) a minimally clinical important pain reduction of ≥ 33%. At baseline, a set of risk factors including pain-related variables, psychological factors, and disability was measured. RESULTS: In a multiple logistic regression analysis, higher patient's expectations, neuropathic pain, no severe pain (< 80 mm visual analogue scale [VAS]) were independently related to long-term continuation of TENS. For the outcome "minimally clinical important pain reduction," the multiple logistic regression analysis indicated that no multisited pain (> 2 pain locations) and intermittent pain were positively and independently associated with a minimally clinical important pain reduction of ≥ 33%. CONCLUSION: The results showed that factors associated with a successful outcome in the long term are dependent on definition of successful outcome.

Ultrasonography of the cervical spine: an in vitro anatomical validation model.

BACKGROUND: Anatomical validation studies of cervical ultrasound images are sparse. Validation is crucial to ensure accurate interpretation of cervical ultrasound images and to develop standardized reliable ultrasound procedures to identify cervical anatomical structures. The aim of this study was to acquire validated ultrasound images of cervical bony structures and to develop a reliable method to detect and count the cervical segmental levels. METHODS: An anatomical model of a cervical spine, embedded in gelatin, was inserted in a specially developed measurement device. This provided ultrasound images of cervical bony structures. Anatomical validation was achieved by laser light beams projecting the center of the ultrasound image on the cervical bony structures through a transparent gelatin. RESULTS: Anatomically validated ultrasound images of different cervical bony structures were taken from dorsal, ventral, and lateral perspectives. Potentially relevant anatomical landmarks were defined and validated. Test/retest analysis for positioning showed a reproducibility with an intraclass correlation coefficient for single measures of 0.99. Besides providing validated ultrasound images of bony structures, this model helped to develop a method to detect and count the cervical segmental levels in vivo at long-axis position, in a dorsolateral (paramedian) view at the level of the laminae, starting from the base of the skull and sliding the ultrasound probe caudally. CONCLUSIONS: Ultrasound bony images of the cervical vertebrae were validated with an in vitro model. Anatomical bony landmarks are the mastoid process, the transverse process of C1, the tubercles of C6 and C7, and the cervical laminae. Especially, the cervical dorsal laminae serve best as anatomical bony landmarks to reliably detect the cervical segmental levels in vivo.

Perinatal maternal stress and serotonin signaling: effects on pain sensitivity in offspring.

It has been estimated that 20% of pregnant women are facing perinatal stress and depression. Perinatal maternal stress has been shown to increase pain sensitivity in offspring. For the treatment of their depressive symptoms, pregnant women are frequently prescribed selective serotonin reuptake inhibitors (SSRIs). Since the descending pain inhibitory circuit matures perinatally, perinatal SSRI exposure has been shown to affect pain sensitivity in offspring. In the present review, we summarize experimental and clinical evidence for the effect of perinatal maternal stress and SSRI exposure on pain sensitivity in offspring. Both experimental and clinical studies show the effect of perinatal maternal stress on regulation of the hypothalamic-pituitary-adrenal (HPA) system and the serotonin pain inhibitory system. Alterations in these two systems likely underlie long-term alterations in the development of pain sensitivity. This review sheds light on the effect of perinatal maternal stress and treatment with SSRIs on offspring pain sensitivity, in relation to the developing HPA system and 5-HT signaling.

Relationship between Sensory Stimulation and Side Effects in Percutaneous Radiofrequency Treatment of the Trigeminal Ganglion.

INTRODUCTION: The objective of this study was to determine the efficacy of percutaneous radiofrequency (RF) treatment of the trigeminal ganglion for treating patients with trigeminal neuralgia, to determine which patients have a long-term benefit, and to evaluate the effect of RF parameters. METHODS: A retrospective study in 28 consecutive patients in combination with a follow-up questionnaire (n = 26, 93% response). RESULTS: An initial treatment effect of 89% was observed, 60% sustained at 12-month follow-up. Major side effects were hypesthesia (56%), dry eye (20%), and masseter muscle weakness (12%). A lower sensory stimulation threshold during treatment was associated with better patient satisfaction (P = 0.016), improved pain relief (P = 0.039), and trended toward more hypesthesia (P = 0.077). DISCUSSION: This low-volume study reported treatment effects in an older population that were similar to previous studies. Only a higher incidence of hypesthesia was detected by long-term follow-up. This study supported the high efficiency of RF treatment, but there was a high level of side effects. Most notable, low sensory stimulation was associated with increased hypesthesia, whereas higher stimulation levels yielded less effectiveness. Further investigation of an optimal sensory stimulation range for percutaneous RF treatment of the trigeminal ganglion was found to be warranted.