Douleur Neuropathique 4 Questionnaire Research Articles

Development and Validation of the Dystonia-Pain Classification System: A Multicenter Study.

Dystonia is associated with disabling nonmotor symptoms like chronic pain (CP), which is prevalent in dystonia and significantly impacts the quality of life (QoL). There is no validated tool for assessing CP in dystonia, which substantially hampers pain management. The aim was to develop a CP classification and scoring system for dystonia. A multidisciplinary group was established to develop the Dystonia-Pain Classification System (Dystonia-PCS). The classification of CP as related or unrelated to dystonia was followed by the assessment of pain severity score, encompassing pain intensity, frequency, and impact on daily living. Then, consecutive patients with inherited/idiopathic dystonia of different spatial distribution were recruited in a cross-sectional multicenter validation study. Dystonia-PCS was compared to validated pain, mood, QoL, and dystonia scales (Brief Pain Inventory, Douleur Neuropathique-4 questionnaire, European QoL-5 Dimensions-3 Level Version, and Burke-Fahn-Marsden Dystonia Rating Scale). CP was present in 81 of 123 recruited patients, being directly related to dystonia in 82.7%, aggravated by dystonia in 8.8%, and nonrelated to dystonia in 7.5%. Dystonia-PCS had excellent intra-rater (Intraclass Correlation Coefficient - ICC: 0.941) and inter-rater (ICC: 0.867) reliability. In addition, pain severity score correlated with European QoL-5 Dimensions-3 Level Version's pain subscore (r = 0.635, P < 0.001) and the Brief Pain Inventory's severity and interference scores (r = 0.553, P < 0.001 and r = 0.609, P < 0.001, respectively). Dystonia-PCS is a reliable tool to categorize and quantify CP impact in dystonia and will help improve clinical trial design and management of CP in patients affected by this disorder. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Prevalence of post-traumatic neuropathic pain after digital nerve repair and finger amputation

Post-traumatic neuropathic pain is a major factor affecting the quality of life after finger trauma and is reported with considerable variance in the literature. This can partially be attributed to the different methods of determining neuropathic pain. The Douleur Neuropathique 4 (DN4) has been validated to be a reliable and non-invasive tool to assess the presence of neuropathic pain. This study investigated the prevalence of neuropathic pain after finger amputation or digital nerve repair using the DN4 questionnaire. Patients with finger amputation or digital nerve repair were identified between 2011 and 2018 at our institution. After a minimal follow-up of 12 months, the short form DN4 (S-DN4) was used to assess neuropathic pain. A total of 120 patients were included: 50 patients with 91 digital amputations and 70 patients with 87 fingers with digital nerve repair. In the amputation group, 32% of the patients had pain, and 18% had neuropathic pain. In the digital nerve repair group, 38% of the patients had pain, and 14% had neuropathic pain. Secondly, of patient-, trauma-, and treatment-specific factors, only the time between trauma and surgery had a significant negative influence on the prevalence of neuropathic pain in patients with digital nerve repair. This study shows that persistent pain and neuropathic pain are common after finger trauma with nerve damage. One of the significant prognostic factors in developing neuropathic pain is treatment delay between trauma and time of digital nerve repair, which is of major clinical relevance for surgical planning of these injuries.

Therapeutic Efficacy of Traditional Chinese Medicine Syndrome-Based Formulae to Neuropathic Pain Caused by Chemotherapy.

Objective:Chemotherapy-induced neuropathic pain (CINP) is a troublesome complication of anti-cancer treatment. The aim of this retrospective study was to investigate the effectiveness of classic Chinese herbal formulae (CHF) Huang Qi Gui Zhi Wu Wu Tang (HQGZWWT) and Dang Gui Si Ni Tang (DGSNT) in the treatment of CINP.Materials and Methods:Douleur Neuropathique 4 (DN4) and Functional Assessment of Cancer Therapy-General (FACT-G) questionnaires were rated at baseline and after 3-monthly CHF treatment.Results:By searching through our medical records of all the CIPN patients from 2018 to 2019, we identified and enrolled 37 patients with Deficiency-Cold syndrome in the study, for whom the treatment of neuropathic pain by regular pharmacotherapies had failed or intolerable. At the third month evaluation with the DN4 questionnaire, 13 patients had symptomatic remission, 15 patients remained stable, and 9 patients had no response to CHF. The 3-month mean DN4 score was significantly higher than that at the baseline (P < .001). After CHF treatment, significant differences in quality of life were noted in the physical, social, emotional, and functional well-being subscales, and in the total score, of the FACT-G (P < .001). No adverse events or instances of disease progression were observed.Conclusions:The results of our small study are the first in the literature to show the clinical effectiveness of CHF for CINP. Combination of HQGZWWT and DGSNT is well tolerated and may offer the possibility to ameliorate CINP more than conventional care can. It merits further investigation.

Frequency Rhythmic Electrical Modulation System (FREMS) to alleviate painful diabetic peripheral neuropathy: A pilot, randomised controlled trial (The FREMSTOP study).

Frequency Rhythmic Electrical Modulated System (FREMS) is a non-invasive treatment for chronic pain conditions, but its place in the treatment algorithm for painful diabetic peripheral neuropathy (PDPN) is unknown. A pilot, open-label, randomised controlled trial in individuals with PDPN inadequately controlled on at least dual neuropathic pain treatments recruited from primary and secondary care. Participants were randomised 1:1 to FREMS+usual care (n=13) versus usual care (n=12). Primary outcome was change from baseline in perceived pain (assessed by visual analogue scale) at 12weeks between treatment groups. Of 25 participants, 14 (56%) were men, and 21 (84%) were White Europeans. Median (IQR) age and duration of diabetes were 64 (56, 68) and 14 (10, 20) years, respectively. At 12weeks, FREMS showed improvements in perceived pain compared with baseline, although the change was not statistically significant from control group (-4.0[-5.0,0.4] vs. 0[-0.3,0.7], p=0.087). There were significant improvements in pain with FREMS, assessed by McGill Pain questionnaire (p=0.042) and Douleur neuropathique-4 questionnaire (p=0.042). More participants on FREMS had greater than 30 percent reductions in perceived pain compared with controls [7/13(54%) vs 0/12(0%), p=0.042] and significant improvements in Patient Global Impression of Change (p=0.005). FREMS intervention had moderate benefits in quality of life, sleep, depression and pain medication use, but these were not statistically significant. FREMS might be used to treat individuals with PDPN inadequately controlled on two classes of neuropathic pain medications and is associated with improvements in pain severity and perceived impact of treatment. A larger, appropriately designed trial assessing its impact in this population is needed.

The Validity and Reliability of a New Modified Persian Version of DN4 to Discriminate Non-neuropathic from Neuropathic

Introduction: One of the popular questionnaires for screening neuropathic pain is the DN4 (Douleur Neuropathique 4) which has been translated into many languages and validated in different populations. So, we wanted to determine the Persian version of this questionnaire’s reliability and validity to differentiate neuropathic pain from other painful non-neuropathic conditions. Methods: This cross-sectional study was conducted on 120 patients who suffered from chronic pain referred to the Physical Medicine and Rehabilitation Department at the three great referral hospitals in Tehran, Iran in 2016. In this study, a modified version of DN4 was used to validate adding a question related to the appearance of pain in an especial joint and adding visual analogue scaling (VAS) score in each item. Results: The modified DN4 questionnaire had high reliability for assessing neuropathic pain with the Cronbach’s alpha coefficient of 0.874. The correlation coefficients obtained by the retest intra-class correlation test ranged from 0.650 to 0.941. Also, the internal consistency of Spearman’s R coefficients ranged from 0.482 to 0.904. Test-retest reliability analysis also showed a higher intraclass correlation (ICC) value in the neuropathic than non-neuropathic pain group (0.85 vs0.73). The modified DN4 questionnaire could effectively discriminate neuropathic pain from non-neuropathic pain with the area under the curve (ROC) of 0.989 (95% CI: 971–1000, P &lt; 0.001). The best cutoff value for the modified DN4 questionnaire to diagnose neuropathic pain was 5, yielding a sensitivity of 98.3% and a specificity of 90.3%. Conclusion: Applying the new modified Persian version of DN4 achieved by adding a VAS score and a new question related to the appearance of pain in an especial joint led to high reliability and validity for this tool to discriminate neuropathic from non-neuropathic pain.

Adjuvant administration of hypertonic saline in lumbar epidural intervention may be associated with successful response in patients with probable neuropathic radicular pain Screened by Douleur Neuropathique 4.

Background: Chronic lumbar radicular pain often accompanies neuropathic pain. The treatment may follow a screening for probable neuropathic pain rather than the definitive diagnosis, which is often difficult in daily practice. However, interventional management may have limited effects on symptoms in patients with neuropathic radicular pain refractory to conservative treatments. The purpose of this study is to evaluate the factors associated with successful responses after lumbar epidural intervention in patients with chronic lumbar neuropathic radicular pain determined by Douleur Neuropathique 4 (DN4).Methods: We retrospectively reviewed 221 chronic lumbar radicular pain patients using a DN4 questionnaire prior to the epidural interventional procedure. The patients were divided into two groups according to the DN4 questionnaire: <4-point DN4 and ≥4 DN4. The numerical rating scale (NRS) for pain intensity, changes in physical functional status, and the use of pain medication were obtained before and 1 month after the procedure. Successful responder was defined based on robust combination of outcome parameters. The factors associated with successful response were analyzed using univariate and multivariate regression.Results: We found 170 (76.9%) patients with DN4 <4 and 51 (23.1%) with a score ≥4. Among the total 221 patients, 129 (58.4%) were successful responders and 92 (41.6%) were non-responders regardless of DN4 score. We observed a significantly lower proportion of successful responders among patients with a DN4 score ≥4 (22, 43.1%) than patients with a score <4 (107, 62.9%) (P=0.012). After adjusting in multivariate regression analysis, the DN4 score was independently associated with response after lumbar epidural intervention (odds ratio [OR]=0.838; 95% confidence interval [CI]=0.718-0.978; P=0.025). In subgroup logistic regression analysis according to the DN4 score, adjuvant administration of hypertonic saline during epidural interventions in patients with a DN4 score ≥4 (OR=3.71; CI=1.142-12.457; P=0.029) was associated with the success of the lumbar epidural procedure at 1 month.Conclusion: The adjuvant use of hypertonic saline in lumbar epidural interventions may be effective at least 1 month after the intervention in patients with probable neuropathic lumbar radicular pain ≥4 using the DN4.

Validation of Complete Hindi Version of Douleur Neuropathique 4 Questionnaire for Assessment of Neuropathic Pain.

Objectives:The Douleur Neuropathique 4 (DN4) questionnaire is a widely used tool for the diagnosis of neuropathic pain (NP). The aim was to validate the Complete Hindi version of DN4 (CH-DN4) questionnaire.Materials and Methods:A systematic translation process was used to translate the original English DN4 into Hindi. The Hindi version was validated among patients appearing in the pain clinic of a tertiary hospital in the capital of Delhi by two different raters. We assessed the internal consistency, test–retest reliability, and inter-rater agreement, validity, sensitivity, specificity, positive and negative predictive values, and area under the curve (AUC).Results:A total of 285 participants, out of which 153 had NP and 132 had non NP (NNP) were included in the study. The results showed our CH-DN4 to have good diagnostic accuracy, a score of ≥ 3.5 was found to be the best cut–off for the diagnosis of NP, with a sensitivity of 0.78, specificity of 0.76, a positive predictive value of 78.5%, and a negative predictive value of 74.5%. Cronbach’s α was 0.82 (95% confidence interval: 0.80–0.84), and interclass correlation coefficients was 0.95. The AUC was >0.8 indicating excellent discrimination between NP and NNP.Conclusion:The CH-DN4 questionnaire has been found to be a reliable and valid screening tool with an excellent power to discriminate between NP and NNP.

Incidence of Neuropathic Pain in Patients with Thoracic Disc Pathologies Presenting with Chronic Upper Back Pain and Correlation of Herniation Grade with Pain Severity.

To determine the incidence of neuropathic pain (NP) in patients with thoracic disc herniation (TDH) and to determine whether there is any correlation between pain severity and herniation grade. A total of 110 patients diagnosed with TDH with chronic non-specific thoracic spine pain were included in our cross-sectional observational study. Data including magnetic resonance imaging findings, bulging, protrusion, extrusion and sequestration were retrospectively analysed. We determined the incidence of NP in patients by administering the self report form Douleur Neuropathique 4 (DN4) questionnaire. Pain severity was assessed using Numeric Rating Scale scores. In our study, 79.1% of TDHs were located below the T7-8 level. The patients were divided into two subgroups on the basis of the results of the DN4 questionnaire: NP subgroup, 43 (39.1%), and non-NP subgroup, 67 (60.9%). Although there was no statistically significant association between presence of NP and herniation grade bulging, protrusion or sequestration (p > 0.05), the rate of herniation in the extrusion grade was statistically significantly higher in patients with NP than in those without NP (p=0.004). The pain severity of the patients with herniation grade extrusion was statistically higher than that of patients with other non-extrusion grades (p=0.035). TDH should be considered in patients with neuropathic chronic back, chest and abdominal pain. If the patient?s pain characteristics indicate NP, a diagnosis of TDH becomes more likely, considering that nearly 4 out of 10 patients with TDH have NP.

Douleur Neuropathique 4 (DN4) stratifies possible and definite neuropathic pain after surgical peripheral nerve lesion.

Douleur Neuropathique 4 (DN4) is a screening questionnaire to help identify neuropathic pain (NP) in clinical practice and research. We tested the accuracy of the DN4 questionnaire in stratifying possible NP (pNP) and definite NP (dNP) in patients operated for breast cancer. We studied 163 patients from a longitudinal cohort of breast cancer operated patients 4-9years after surgery. pNP or dNP were classified according to the NP grading system. Surgeon-verified intercostobrachial nerve resection was used as a confirmatory test for dNP. A receiver-operating characteristic (ROC) curve analysis was performed and the area under the curve (AUC) was calculated to test the diagnostic accuracy (sensitivity, specificity, positive and negative predictive values) of the DN4. Additionally, we studied clinical factors that associated with a positive screening outcome in the interview part of the DN4 (DN4i). DN4i and DN4 showed significant accuracy in stratifying patients with pNP or dNP with cut-off scores 3 and 4 resulting to sensitivity of 66.2% and 79.4% and specificity of 77.8% and 92.6%, respectively. pNP and dNP patients showed differences in sensory descriptors of pain according to DN4i items. Screening positive on DN4i associated with dNP and younger age. Full DN4 could stratify pNP and dNP patients in a chronic postsurgical NP patient group operated for breast cancer. Additionally, DN4i showed significant accuracy in stratifying pNP and dNP, but an examination is necessary to obtain proper accuracy. Demographic factors may have an impact on the screening outcome of DN4i. DN4 stratifies possible and definite postsurgical peripheral neuropathic pain. DN4i may also show this, but full DN4 is more accurate. We confirm DN4i as a valid screening tool for NP.

Pharmacological management of neuropathic pain in India: A consensus statement from Indian experts

Neuropathic pain (NeP) constitutes a major pain-related disorder, which is often underdiagnosed and undertreated. Adverse physical, psychological, and economic consequences associated with NeP lead to poor quality of life. Burden of NeP in developing countries like India is colossal. Various international guidelines provide effective approaches to diagnose and manage NeP. However, differences in the genetic makeup of Indian population can result in subtle differences in clinical response, considering their low body weight, drug metabolism ability, and pain perception. Similarly, treatment-related adverse effects may also vary. Practice of Indian physicians may also differ for choice of drugs based on their availability and affordability. In the absence of country-specific guidelines, this document could serve as a guiding tool for health-care providers, ensuring uniformity in the treatment of NeP. Thus, applicability of all recommendations from any of these guidelines in Indian setting demands careful evaluation. Clinical experience of Indian physicians suggests that there are lot many challenges (e.g., busy outpatient departments, nonavailability of screening questionnaires in regional languages, and availability and affordability of medications) faced by them when managing NeP. In addition, in India, there are no country-specific guidelines that would help them to address these challenges. The objective for this consensus was to develop an expert opinion guideline to harmonize the management of NeP in India. The expert panel consisted of experts from various specialties such as pain medicine, anesthesiology, diabetology, neurology, and orthopedics. The panel critically reviewed the existing literature evidence and guideline recommendations to provide India-specific consensus on the management of NeP. The final consensus document was reviewed and approved by all the experts. This expert opinion consensus will help health-care professionals as a guiding tool for effective management of NeP in India. Use of Douleur Neuropathique 4 (DN4) questionnaire for NeP screening should be routine in day-to-day clinical practice. For effective utilization of DN4 questionnaire, it should be converted to regional language. If DN4 questionnaire screening fails to identify NeP, it should not be disregarded and should not replace the sound clinical judgment from the treating physician. Diagnostic tests may be considered as a supplement to clinical judgment. Cost-effective treatment should be the initial choice. Dosing should be individualized based on efficacy and tolerability. Tricyclic antidepressants (TCAs), gabapentinoids, and serotonin-norepinephrine reuptake inhibitors (SNRIs) can be considered among initial choices. Tramadol can be considered as a second-line add-on treatment for NeP if there is partial response to the first-line agent either alone or in combination. Fixed-dose combination (FDC) of gabapentinoids such as pregabalin (75 mg) with TCA such as nortriptyline (10 mg) is synergistic and improves treatment adherence. Among other treatments, Vitamin B12 (methylcobalamin) can be used either alone or in combination for the management of NeP. Use of Vitamin D and steroids should be limited to specific NeP in individual cases. Referral to pain specialists can be considered if two drugs fail to provide relief in NeP.

Persistent postherniorrhaphy pain following inguinal hernia repair: A cross-sectional study of prevalence, pain characteristics, and effects on quality of life

IntroductionChronic inguinal pain due to the inguinal hernia repair is still a serious consideration, and its incidence is evident in approximately 3%–6% of the patients. The purpose of this study was performed to assess the prevalence of chronic pain after inguinal hernia repair and the effects on the quality of life in our patient. MethodsThe records of the patients who were 18 years of age or older and had had an inguinal hernia repair under spinal anesthesia after receiving a diagnosis of inguinal hernia at this hospital from 2009 to 2015 were accessed through the hospital's data system. Patients who had signed the informed consent agreement were given an Inguinal Pain Questionnaire (IPQ) and a Douleur Neuropathique 4 (DN-4) questionnaire after recording their demographic data on the appointment day. Surgical incision line was evaluated with a dolorimeter and mild touch hypoesthesia, needle-touch hypoesthesia, brushing allodynia were evaluated with cotton, and 0.711 mm diameter Von-Frey filament (Touch-Test Sensory Evaluator Kit; North Coast Medical, Inc., Gilroy, CA, USA). ResultsThe total number of patients who had ASA I-II scores and who had undergone a one-sided inguinal hernia repair under spinal anesthesia in elective conditions with at least three or more months of recovery time months was 619. Of these 264 patients, 203 with absence of pain (score of the severest pain over the past week and now was 0) were classified as the Non-Pain group and 61 patients with inguinal pain (score of the severest pain over the past week or now was 1 or more) were classified as the Pain group.The incidence of chronic pain after inguinal hernia surgery was 23.48% (n = 61) in our study. The pain was localized at and near the surgical incision and radiated into the scrotum in 17.73% (n = 36) of the male patients having chronic pain. While chronic pain developed in 60 out of 239 patients who had pain prior to the surgery. The presence of pain prior to the surgery was evaluated as an effective factor for the chronic groin pain. Neuropathic pain was detected with the DN-4 questionnaire in 6 (2.95%) out of 203 patients who stated that they had no pain during the physical examination and the week prior to the exam. The frequency of chronic pain after inguinal hernia repair was found 23.48% in our study. This is the same rate as previously reported. Quality of life of these patients was affected. We believe that there is an urgent need for prospective randomized studies with the aim of determining a standardized methodology towards preventive measures after determining the risk factors of chronic pain developed in the post inguinal hernia repair period.

Development and validation of Arabic version of the douleur neuropathique 4 questionnaire.

Introduction:The douleur neuropathique 4 (DN4) questionnaire is a widely used tool for diagnosis of neuropathic pain (NP). The aim was to translate, culturally adapt, and validate the DN4 questionnaire in Arabic.Methods:A systematic translation process was used to translate the original English DN4 into Arabic. After the pilot study, the Arabic version was validated among patients with chronic pain in two tertiary care centers. The reliability of the translated version was examined using internal consistency, test-retest reliability, and intraclass correlation coefficients. We examined the validity of the Arabic DN4 via construct validity, concurrent validity (associations with the numeric rating scale, brief pain inventory, and Self-Completed Leeds Assessment of Neuropathic Symptoms and Signs [S-LANSS]), face validity, and diagnostic validity. To investigate the responsiveness, the translated DN4 was administered twice among the same group of patients.Results:A total of 142 subjects (68 men, 74 women) were included in the study. Cronbach's α was 0.67 (95% confidence interval [CI]: 0.59–0.75), and interclass correlation coefficients was 0.81 (95% CI: 0.76–0.87). The DN4 was moderately associated with the S-LANSS questionnaire. Results showed our Arabic DN4 to have good diagnostic accuracy, with area under the curve of 0.88 (95% CI: 0.82–0.94). As with the original version, a score of ≥4 was found to be the best cut-off for the diagnosis of NP, with a sensitivity of 88.31%, specificity of 74.47%, a positive predictive value of 85%, and a negative predictive value of 80%. Most patients found the DN4 questionnaire to be clear and easy to understand, and thought the questionnaire items covered all their problem areas regarding their pain.Conclusion:Our Arabic version of the DN4 is a reliable and valid screening tool that can be easily administered among patients to differentiate between NP and non-NP.

Chronic postsurgical pain and neuropathic symptoms after abdominal hysterectomy: A silent epidemic.

Chronic postsurgical pain (CPSP) is an important clinic problem. It is assessed that prevalence of chronic pain extends to 30% but it is contended that there are various risk factors. We aimed to evaluate the prevalence of chronic pain after hysterectomy, risk factors of chronicity, neuropathic features of pain, and sensorial alterations at surgery area.Between years 2012 and 2015, 16 to 65 ages old patients that electively undergone total abdominal hysterectomy bilateral salpingo-oophorectomy and passed minimum 3 months after surgery were included to study. Visual analog scale (VAS) and Douleur Neuropathique 4-questionnaire (DN-4) surveys were used to evaluate pain symptoms, algometry device was used for evaluating abdominal pressure threshold and Von Frey Filament was used for sensorial alterations.Ninety-three of 165 eligible patients were included to study. As the groups were compared by demographic data, no difference was obtained (P > 0.05). There was no difference between groups regarding patient and surgery attributes (P > 0.05). Most frequently performed incision type was Pfannenstiel. Neuropathic symptoms were observed in 90 patients (96.8%). Sensorial alterations as hypoesthesia and hyperesthesia were detected around abdominal scar in 18 patients (19.4%) with pinprick test.Neuropathic symptoms should not be ignored in studies evaluating CPSP and a standard methodology should be designed for studies in this topic.

Effect of preoperative gabapentin on pain intensity and development of chronic pain after carpal tunnel syndrome surgical treatment in women: randomized, double-blind, placebo-controlled study.

Effective postoperative analgesia is important for reducing the incidence of chronic pain. This study evaluated the effect of preoperative gabapentin on postoperative analgesia and the incidence of chronic pain among patients undergoing carpal tunnel syndrome surgical treatment. Randomized, double-blind controlled trial, Federal University of São Paulo Pain Clinic. Forty patients aged 18 years or over were randomized into two groups: Gabapentin Group received 600 mg of gabapentin preoperatively, one hour prior to surgery, and Control Group received placebo. All the patients received intravenous regional anesthesia comprising 1% lidocaine. Midazolam was used for sedation if needed. Paracetamol was administered for postoperative analgesia as needed. Codeine was used additionally if the paracetamol was insufficient. The following were evaluated: postoperative pain intensity (over a six-month period), incidence of postoperative neuropathic pain (over a six-month period), need for intraoperative sedation, and use of postoperative paracetamol and codeine. The presence of neuropathic pain was established using the DN4 (Douleur Neuropathique 4) questionnaire. Complex regional pain syndrome was diagnosed using the Budapest questionnaire. No differences in the need for sedation, control over postoperative pain or incidence of chronic pain syndromes (neuropathic or complex regional pain syndrome) were observed. No differences in postoperative paracetamol and codeine consumption were observed. Preoperative gabapentin (600 mg) did not improve postoperative pain control, and did not reduce the incidence of chronic pain among patients undergoing carpal tunnel syndrome surgery.

Validation of a New Arabic Version of the Neuropathic Pain Diagnostic Questionnaire (DN4).

The "Douleur Neuropathique 4 (DN4) questionnaire" was developed for screening neuropathic pain. The purpose of this work was to validate the DN4 questionnaire in the standard Arabic language. First, the questionnaire was translated and semantically adapted to Arabic according to the international guidelines for cross-cultural adaptation. Second, a prospective observational study was performed to validate this questionnaire. A total of 195 patients with chronic pain (n = 99 with neuropathic pain and n = 96 without neuropathic pain) were enrolled in the study. The internal consistency Kuder-Richardson's Formula 20 for the whole DN4 questionnaire was 0.86 (P < 0.001) and the intraclass correlation coefficient 0.99 (95% CI: 0.99 to 1.00). The test-retest reliability kappa coefficient for each item ranged from 0.92 to 1.00. Using a receiver-operating characteristic (ROC) curve analysis, the areas under the curve were 0.94 and 0.97 for the 7-item DN4 and 10-item DN4, respectively. A cut-off score of 3 resulted in a sensitivity of 97.0% and a specificity of 82.3% for the 7-item DN4, while a cut-off score of 5 for the 10-item DN4 resulted in a sensitivity of 93.0% and a specificity of 95.8%. Tingling, numbness, and hypoesthesia to touch and to pricking were the most discriminating pain items. The sensitivity and specificity of the 7-item DN4 and 10-item DN4 were not influenced by either pain severity or educational level. In conclusion, this new Arabic version DN4 questionnaire is a simple, reliable, and valid tool for discriminating between neuropathic and non-neuropathic pain. It represents a useful tool in clinical setting and population-based studies.

Correlation Between DNA Methylation of TRPA1 and Chronic Pain States in Human Whole Blood Cells.

Neuro-immune interactions with functional changes in the peripheral blood cells including changes in the transient receptor potential ankyrin 1 (TRPA1) appear to play a pivotal role in the development of chronic pain in humans. The aim of this study was to examine the association between TRPA1 DNA methylation in whole blood cells and the pain states in chronic pain patients. After collecting blood samples from 12 chronic pain patients, the authors measured DNA methylation levels in whole blood cells. Significant associations between the patient's demographic data and the chronic pain states were determined by a multiple linear regression analysis that used age, body mass index, pain duration, depression, anxiety, cognitive impairment, activities of daily living, neuropathic pain, and pain states as the dependent variables, and the TRPA1 DNA methylation levels as the independent variables. Multiple regression analysis revealed a significant correlation between increases of the methylation levels of the CpG island in the TRPA1 gene and increases in the number of neuropathic pain symptoms, which were evaluated using the Douleur Neuropathique 4 (DN4) questionnaire. Decreases in the TRPA1 mRNA expression were also significantly related to increases in the DN4 score. The presence of a burning sensation, which is one of pain symptoms in the DN4 questionnaire, was significantly correlated with the increase in DNA methylation level of TRPA1. TRPA1 DNA methylation levels in whole blood cells appear to be associated with pain symptoms in chronic pain patients.

Validation of the Korean Version of the DN4 Diagnostic Questionnaire for Neuropathic Pain in Patients with Lumbar or Lumbar-Radicular Pain.

PurposeTo evaluate the diagnostic value of the Korean version of the Douleur Neuropathique 4 (DN4) questionnaire and to validate this questionnaire in terms of psychometric properties in patients with chronic pain due to degenerative spinal disease.Materials and MethodsThe Korean version of the DN4 questionnaire, which was translated and linguistically validated by the MAPI Research Group, was tested on 83 patients with lumbar or lumbar-radicular pain. Test-retest reliability was evaluated in a subsample of 40 patients who completed two assessments with an interval of 2 weeks. Nociceptive pain and neuropathic component pain were diagnosed in 40 and 43 patients, respectively.ResultsThe Cronbach's α coefficient of internal consistency was 0.819, and the test-retest intraclass correlation coefficient (3, 1) (95% confidence interval) was 0.813 (0.776–0.847) (n=40). The area under the receiver-operator characteristics curve was 0.953 (p<0.001), with 95% confidence interval between 0.869 and 0.990. The Korean version of the DN4 questionnaire showed a sensitivity of 100% and 87.1%, and a specificity of 88.2% and 94.1% at the cutoff value of 3/10 and 4/10, respectively, for discriminating neuropathic component pain.ConclusionThe present study demonstrated the good discriminatory power of DN4 between nociceptive pain and neuropathic component pain in patients with lumbar or lumbar-radicular pain.

Primary Burning Mouth Syndrome: A Questionnaire Study of Neuropathic and Psychological Components.

The pathophysiology of primary burning mouth syndrome (BMS) is extensively debated but poorly understood. The aim of the study was to evaluate neuropathic and psychological components of BMS in patients with primary BMS. Subjects were recruited through a consultation dedicated to mouth diseases, during which a diagnosis of primary BMS was assessed. Patients answered the abbreviated Douleur Neuropathique 4 questionnaire (DN4i), the Hospital Anxiety and Depression Scale (HADS) and the questionnaire de la douleur de Saint-Antoine (QDSA), the French version of the McGill pain questionnaire. Thirty-five patients with primary BMS were included in the study: 31% of them had a DN4i score in favour of neuropathic pain and 34.3% had a HADS overall score in favour of anxiety and depressive disorder. Both physiological and psychological aspects of BMS need to be actively investigated by clinicians to successfully manage these patients. The physiological and psychological aspects are not mutually exclusive. The DN4i and the HADS are easy-to-use tools and could be used in an initial assessment of BMS patients.

The long-term changes in pain-related symptomatology of inguinal herniafollowing 2 different herniorrhaphy techniques

To compare the changes in pain-related symptoms of inguinal hernias from initial admission to postoperative month 6 following 2 herniorrhaphy techniques. Patients with unilateral inguinal hernias were scheduled for either Lichtenstein or self-gripping polypropylene mesh repair. Patients were preoperatively evaluated with a visual analog scale (VAS) and a Turkish version ofthe Douleur Neuropathique 4 (DN4) questionnaire and the complaints related to pain were noted. After surgery, patients were discharged without early complications. Patients were reassessed at postoperative month 6. The late-term complaints of pain as well as neurological findings were evaluated using the VAS and the Turkish version of the DN4 questionnaire. Quality of life was also assessed with the Nottingham Health Profile (NHP). Thirty-four patients underwent conventional Lichtenstein repair and 19 patients underwent self-gripping polypropylene mesh repair. Even though decreases in VAS intensity scores for both hernia repair techniques were noted at postoperative month 6 when compared to the preoperative period, no significant changes were found in pain, VAS, total DN4, or NHP scores between groups. Despite its ease of application and short time duration, self-gripping polypropylene mesh repair was not found to be superior to conventional Lichtenstein hernia repair in terms of reducing pain related to inguinal hernia.

Effects of ozone applied by spinal endoscopy in patients with chronic pain related to failed back surgery syndrome: a pilot study.

IntroductionIn the last two decades, ozone has emerged as a treatment for low back pain, applied by means of minimally invasive techniques.ObjectiveThe aim of this study is to assess the effect and safety of ozone therapy applied in the epidural space for chronic pain related to failed back surgery syndrome.MethodsThe investigators studied 13 sequential patients of both sexes, between 18 and 70 years old, with persistent chronic pain (more than six months) in the lumbar region and in the lower limbs related to failed back surgery syndrome (FBSS). Pain was classified as neuropathic and non-neuropathic regarding the topography (lumbar and lower limb), based on the DN4 (Douleur Neuropathique 4) questionnaire. The patients received the ozone gas in the lumbar epidural space via spinal-sacral endoscopy. Clinical evaluation was performed before, immediately after (24 hours), and 1, 3, and 6 months after intervention with visual analog scale and Oswestry Disability Index (ODI).ResultsOverall, the patients had 43.7% reduction of lumbar pain, 60.9% reduction in leg pain in six months followed by 44.0% of improvement in ODI. The reduction of pain and in the disability index was markedly greater in patients with non-neuropathic predominant pain, 95.2%, 80.6%, and 75.3% improvement in lumbar, leg pain, and ODI respectively, while neuropathic predominant pain patients experienced only 12.5%, 42.4%, and 20.9% improvement, also respectively. No neurological or infectious complications were observed acutely or during the follow-up. The present data suggests that epidural ozone might be a therapeutic option for persistent low back pain, especially in non-neuropathic predominant pain patients, but double-blind controlled studies are still required to prove its efficacy.