Pain Research最新文献

{"title":"Neurofeedback reveals mechanism of phantom limb pain to reduce pain","authors":"T. Yanagisawa","doi":"10.11154/pain.36.35","DOIUrl":"https://doi.org/10.11154/pain.36.35","url":null,"abstract":"Phantom limb pain is an intractable pain for which no effective treatment has been establish ed. The pain has been attributed to abnormal plastic changes in the sensory motor cortex corresponding to the deafferented body part. Some feedback therapy such as mirror therapy have been applied to modify the abnormal cortical changes, although it is not been unveiled how to change the corresponding sensory motor cortex to reduce pain. We have applied neural decoding to magnetoencephalography (MEG) to extract motor information of the upper limb, and realized a Brain–Computer Interface (BCI) that allows patients to operate a prosthetic hand as if they were moving a phantom limb. In addition, we have demonstrated that neurofeedback (NF) training to control the BCI induced plastic changes in the patient’s sensorimotor cortex and changes in the pain. Actually, the training to attenuate the motor representation of the phantom limb reduced the pain. In addition, we evaluated the efficacy of the NF training by a blinded crossover trial of training with three consecutive days. Twelve patients were trained to control the phantom limb images, that were controlled through BCI. After three days NF trainings, the pain assessed with the Visual Analogue Scale (VAS) was significantly reduced for five days. Furthermore, the pain reduction was associated with the attenuation of the motor representation of phantom limb. These results suggest that the residual motor representations of phantom limb cause the phantom limb pain. We have demonstrated that the NF training elucidates the pathogenesis of chronic pain and develops a new treatment.","PeriodicalId":41148,"journal":{"name":"Pain Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45067605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a Japanese version of the Pain Disability Index: translation and linguistic validation","authors":"Keiko Yamada, A. Mibu, Sonora Kogo, M. Iseki, Tomohiko Nishigami","doi":"10.11154/pain.36.1","DOIUrl":"https://doi.org/10.11154/pain.36.1","url":null,"abstract":"The Pain Disability Index ( PDI ) is a self–reported outcome measure initially developed in English to assess disability caused by pain in seven dimensions of daily life activity, including family ⁄ home responsibilities, recreation, social activity, occupation, sexual behavior, self–care, and life–support activity. This study aimed to develop a linguistical ly valid Japanese version of the PDI ( PDI–J ) according to the guidelines for the translation and cultural adaptation of patient–reported outcome measures establish ed by the task force of the International Society for Pharmacoeconomics and Outcomes Research. A draft of the PDI–J was developed through a forward translation of the original PDI from English to Japanese, reconciliation of the translation, back– translation from Japanese to English, and harmonization. We subsequently conducted a cognitive debriefing in five patients using the PDI–J draft and reviewed it before finaliz ing a linguistically valid PDI–J. We also considered a five–item version of the PDI ( PDI–5–J ) , which excluded two items ( sexual behavior and life–support activity ) from the original version. This consideration was made for brevity and because sexual behavior is a considerably personal parameter that some patients may be reluctant to answer and life–support activity because it was considered ambiguous in Japanese. Therefore, we were able to develop a linguistically valid PDI–J and PDI–5–J through this process. Further study is warranted to confirm the psychometric validity and reliabili ty of the two indices","PeriodicalId":41148,"journal":{"name":"Pain Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42272031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association between cluster analysis for multiple measures and International Classification of Diseases 11th revision as classification of chronic pain patients","authors":"A. Kawai, Keiko Yamada, Saeko Hamaoka, Satoko Chiba, K. Wakaizumi, K. Yamaguchi, M. Iseki","doi":"10.11154/PAIN.35.141","DOIUrl":"https://doi.org/10.11154/PAIN.35.141","url":null,"abstract":"Cluster analysis can classify patients with chronic pain using multiple scales, and classification of chronic pain will be adopted in the International Classification of Diseases 11 th revision (ICD– 11 ) in 2022 . In the present study, we aimed to investi-gate whether cluster analysis was practical for classifying chronic pain and to determine the association between these two classifications for chronic pain. This study included 229 patients with chronic pain who completed a self–reported questionnaire at the first visit to a pain clinic in a university hospital. Patients were clustered using a two–step cluster analysis (TSCA), a machine learning method, for the scores of nine questionnaires. Thereafter, the proportions of clusters among major and several minor classifications were tested using the analysis of covariance adjusted for age and doctor. The following three clusters were calculated using TSCA: mild, moderate, and severe symptoms. Among the major classifications of chronic pain in ICD– 11 , the distribution of clusters significantly differed, but the proportions of these three clusters in each chronic pain classification did not differ. Our findings suggested that TSCA for multiple measures may be a better approach for the classification of chronic pain, but its classification is not associated with the classification of chronic pain in ICD– 11 . The P–values of chronic widespread primary pain and others were calculated for comparison with chronic localized primary pain by the analysis of covariance using Dunnett’s test. The P–values of chronic centralized and other neuropathic pain were calculated for comparison with chronic peripheral neuropathic pain by the analysis of covariance using Dunnett’s test. The P–values of chronic non–specific and other pain were calculat ed for comparison with chronic structurally changed musculoskeletal pain by the analysis of covariance using Dunnett’s test. The analysis of covariance was adjusted for age and doctor.","PeriodicalId":41148,"journal":{"name":"Pain Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42518180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics of pain–related factors in subgroups based on central sensitivity syndromes and pain in musculoskeletal pain patients: a cluster analysis","authors":"H. Shigetoh, Yoichi Tanaka, Masayuki Koga, M. Osumi, S. Morioka","doi":"10.11154/PAIN.35.133","DOIUrl":"https://doi.org/10.11154/PAIN.35.133","url":null,"abstract":"Central sensitization (CS) and psychological factors are associated with pain intensity. However, it has remained unclear whether the effects of central sensitivity syndromes and cognitive ⁄ emotional factors differ depending on the severity of pain and the pain quality. Our purposes were to perform subgrouping based on central sensitivity syndromes and pain intensity, and to clarify the difference in central sensitization syndrome and pain intensity between subgroups. Fifty–nine patients with musculoskeletal pain were included in this cross– sectional study. Pain intensity and psychological problems were assessed with Central sensitization inventory (CSI–9), Short–Form McGill Pain Questionnaire 2 (SFMPQ2), Hospital Anxiety and Depression Scale (HADS), Pain Catastrophizing Scale (PCS–4). The cluster analysis with a ward method was used to divide patients into subgroups based on central sensitization syndrome and pain intensity. In addition, Kruskal–Wallis test, multiple comparison (Bonferroni method), and Fisher’s exact test were performed to compare clinical outcomes between subgroups. The level of significance was set at 5%. The cluster analysis classified into three subgroups. One subgroup of patients (n=11) was characterized by high level of central sensitivity syndromes, pain intensity and psychological problems. A second subgroup (n=19) was characterized by low level of central sensitivity syndromes, moderate level of pain intensity, high level of psychological problems. The third subgroup (n=29) was characterized by low level of central sensitivity syndromes, pain intensity and psychological problems. That is, one subgroup was mainly affected with central sensitivity syndromes, and another subgroup was affected psychological factors. These results indicated the differences in pain mechanism among subgroups.","PeriodicalId":41148,"journal":{"name":"Pain Research","volume":"35 1","pages":"133-140"},"PeriodicalIF":0.0,"publicationDate":"2020-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44082701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of influence factors on chronic pain in each generation","authors":"Y. Terajima, Yukiko Shiro, Shuichi Aono, Keiko Owari, Kenichi Arai, Shinsuke Inoue, T. Matsubara, Makoto Nishihara, T. Ushida","doi":"10.11154/pain.35.107","DOIUrl":"https://doi.org/10.11154/pain.35.107","url":null,"abstract":"Purpose: The aim of this study is to clarify the difference in influencing factors for chronic pain in each generation. Method: There were 2 , 298 patients who visited Aichi Medical University Pain Center. The patient pedestrian score measured using iPad at the first visit was analyzed. Measurement items are Numerous Rating Scale (NRS), Pain Disability Assessment Scale (PDAS), Hospital Anxiety and Depression Scale (HADS), Pain Catastrophizing Scale (PCS), Pain Self–Efficacy Questionnaire (PSEQ), and Athens Insomnia Scale (AIS). For these items, average values were calculated for each age group of 10 years. Furthermore, linear regression was performed using NRS and PDAS as objective variables and other items as explanatory variables. A p value < 0 . 05 was considered significant. Result: NRS, PDAS and PCS were high after the 30 s, HADS and AIS were high in the working generation, and PSEQ was low in the working generation. The number of patients is the lowest in teens and increased in the 40 s, and there were many patients in the subsequent generations, with the largest number of men and women in their 60 s. In the multiple regression analysis with NRS as the objective variable, AIS was selected with a significant difference in the generations excluding the 80 s. In the 20 s and 70 s, PCS was selected. In the multiple regression analysis with PDAS as the objective variable, AIS was selected in the teens to 60 s, PSEQ was selected in the 30 s and over, and HADS depression was selected in the 40 s and over. Conclusion: We analyzed pain–related factors for each generation and found dif-ferences between generations. The working generation was worse in psychology and sleep than the other generations, and these affected pain symptoms.","PeriodicalId":41148,"journal":{"name":"Pain Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45892823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Central sensitization and chronic pain: study for migraine","authors":"K. Hirata, D. Danno, S. Kikui, Keisuke Suzuki, T. Takeshima","doi":"10.11154/pain.35.73","DOIUrl":"https://doi.org/10.11154/pain.35.73","url":null,"abstract":"Refractory chronic headaches greatly impair the quality of life of migraine patients and also reduce social productivity. To elucidate the pathophysiology of the supersensitive brain state of refractory migraine attacks, and to discover the treatment and prophylaxis for the refractory chronic migraine, we analyzed a brain electric field under the light stimulation–induced brain supersensitivity. As a result, we found suppression of the cortical hyperexcitation only in patients with migraine without aura. This result suggested that the suppression of the cortical hyperexcitation by cortical spreading depression may have a role for inhibition of excitation in limbic system, vestibular system and the vomiting center. Next, cranial autonomic symptoms in patients with migraine have recently received attention. We showed that central sensitization, assessed by central sensitization inventory questionnaire, was more prevalent in migraine patients with cranial autonomic symptoms compared with those without cranial autonomic symptoms, suggesting a possible role of central sensitization in comorbid autonomic symptoms in migraine. Central sensitization is postulated to participate in not only severe pain but also in various symptoms such as fatigue, sleep disturbances, anxiety and depres sion in chronic pain syndrome. We believe our study results from migraine patients shed some light on the role of central sensitization in pathophysiology of chronic pain syndrome, but the elucidation of these relationships require further studies.","PeriodicalId":41148,"journal":{"name":"Pain Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44205042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shuttle maze test: A novel operant method to repeatedly assess presumed nociception in freely behaving rats after nerve injury","authors":"Ken-ichiro Hayashida","doi":"10.11154/pain.35.92","DOIUrl":"https://doi.org/10.11154/pain.35.92","url":null,"abstract":"Operant methods that allow animals to avoid painful stimuli are interpreted to assess the aversive quality of pain, however, such measurements involve stimulation delivery by the experimenter and can induce fear, anxiety, or stress in animals, all of which can affect nociceptive threshold or mask pain behaviors. Here we developed a new operant method, the shuttle maze test, to assess the aversive quality of mecha nical stimuli in rats after L5–L6 spinal nerve ligation (SNL) without externally applied stimuli by the experimenter. The shuttle maze test is based on the motivation for chocolate flavor cereal as a treat, and animals ambulates back and forth between two treat feeders by taking either a short route with a prickly–surfaced arch or a longer route with a smooth floor. The preference for taking the short route is a primary outcome measure of the test. Importantly, the animals do not have any painful consequences of not performing the task in the shuttle maze. SNL reduced the preference for the short route with the arch, correlated with hypers ensitivity in the hindpaw. Oral gabapentin (30 and 100 mg/kg), pregabalin (100 mg/kg), and duloxetine (50 mg/kg) restored the short route preference and reduced hypersensitivity in SNL rats. These results suggest that SNL injury alters behavior in the shuttle maze test and that shuttle maze test shows comparable results to reflexive hypersensitivity after SNL in response to analgesics.","PeriodicalId":41148,"journal":{"name":"Pain Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45399970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Roles of mesocortico–limbic system in exercise–induced hypoalgesia","authors":"K. Kami, F. Tajima, E. Senba","doi":"10.11154/pain.35.80","DOIUrl":"https://doi.org/10.11154/pain.35.80","url":null,"abstract":"","PeriodicalId":41148,"journal":{"name":"Pain Research","volume":"35 1","pages":"80-91"},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41577933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multifaceted evaluation of central post–stroke pain","authors":"N. Mori, K. Hosomi, M. Shibata, H. Kishima, Y. Saitoh","doi":"10.11154/pain.35.99","DOIUrl":"https://doi.org/10.11154/pain.35.99","url":null,"abstract":"Objective: The goal of treating chronic pain is becoming more focused on improving ADL and QOL than on pain itself. In this study, we evaluated patients with central post–stroke pain (CPSP) by a multifaceted evaluation and examined factors related to ADL and QOL. Methods: Patient background, stroke information, motor and sensory disturbance, pain site and duration, pain scales (VAS and Short–form McGill Pain Questionnaire 2 ; SF–MPQ 2 ), Pain Catastrophizing Scale, Hospital Anxiety and Depression Scale (HADS), Pain Disability Assessment Scale (PDAS), EQ– 5 D– 5 L were obtained from 41 patients with CPSP. The factors related to PDAS and EQ– 5 D– 5 L were investigated by univariate and multivariate analyses. Results: The univariate analysis showed that the PDAS was associated with motor disturbance scale (SIAS–motor: r=− 0 . 67 , p< 0 . 01 ) and pain scales (VAS: r= 0 . 32 , p= 0 . 04 ; SF–MPQ 2 : r= 0 . 31 ; p= 0 . 04 ), while the QOL value (EQ– 5 D– 5 L) was associated with motor disturbance scale (SIAS–motor: r= 0 . 55 , p< 0 . 01 ), pain scales (SF–MPQ 2 : r=− 0 . 54 , p< 0 . 01 ; VAS: r=− 0 . 48 , p< 0 . 01 ), degree of sensory disturbance (p< 0 . 01 ), and mood status (HADS depression item: r=− 0 . 56 , p< 0 . 01 ; HADS anxiety item: r=− 0 . 37 , p< 0 . 01 ). In multivariate analysis, the PDAS was largely affected by SIAS–motor and SF–MPQ 2 , and the QOL value was affected by multiple factors such as the SIAS–motor, SF–MPQ 2 , degree of sensory disturbance and HADS depression item. Conclusions: The ADL and QOL in patients with CPSP reflect not only pain, but also motor and sensory impairments, and mood status, which should be noted when assessing.","PeriodicalId":41148,"journal":{"name":"Pain Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49612855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Right–side predominance of the central amygdala activation in trigeminal inflammatory pain model","authors":"Yukari Takahashi, Yuta Miyazawa, Daigo Arimura, Y. Sugimura, F. Kato","doi":"10.11154/pain.35.10","DOIUrl":"https://doi.org/10.11154/pain.35.10","url":null,"abstract":"The central amygdala (CeA), especially the capsular part (CeC), receives nociceptive information from the superficial layer of the spinal dorsal horn and the caudal subnucleus of the trigeminal nucleus via the lateral parabrachial nucleus (LPB). The synapse between LPB and CeC neurons, forming the final stage of this spino–(trigemino–)parabrachio–amygdaloid pathway, undergoes robust synaptic potentiation in various types of rodent pain models, thus contributing to the enhanced nociception–emotion link in persistent pain. A remarkable feature of the CeA activation in animals with inflammatory pain is the right–side predominance. Using a trigeminal pain model by injecting formalin to the upper lip unilaterally, we analyzed the right–left differences in LPB–CeC synaptic potentiation and c–Fos expression in the LPB and the amygdala to reveal what determines the right– predomi nance in CeA activation. Unilateral trigeminal inflammation induced 1 ) a significant bilateral increase in c–Fos–expression in the LPB, 2 ) a right–predominant LPB–CeC synaptic potentiation and 3 ) a right–predominant increase in c– Fos–expression in the CeA, regardless of the side of the inflammation. Though c– Fos expression in the basolateral amygdala (BLA) was not significantly increased in this model, the number of c–Fos positive cells between the BLA and CeA was cor-related compared to that between the LPB and CeA. Therefore, the right–side predominance of the CeA activation in the inflammatory pain models would not be a simple consequence of lateralized LPB activation but rather involves non–Hebbian plasticity inherent to the CeA neurons and inputs they receive.","PeriodicalId":41148,"journal":{"name":"Pain Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46037791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}