著者

川田 倫子 牛田 享宏 池内 昌彦 川上 照彦 山中 紀夫 池本 竜則 谷 俊一 小松 誠

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.21, no.3, pp.127-132, 2006-08-20 (Released:2013-10-24)

参考文献数

10

被引用文献数

3 6

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Hip joint associated pain is known to distribute widely in affected thigh or lower leg and generally not restricted in hip joint area.However detail feature of hip joint associated referred pain is not sufficiently clarified. Therefore the aim of this study is to characterize the types of distribution of hip joint related pain and to give our opinion about underlying neurophysiological mechanisms of hip joint referred pain. Of 36 severe osteo-arthritis joints, 83% of the joints showed remote pain area and 18% of the joints showed pain restricted only in inguinal area. Fourteen percent of the joints had far remote pain in lower leg area. L5 root block study was conducted in 7 cases. In all cases remote referred pains were attenuated at least 2 or 3 days and long lasting pain improvement was achieved in one case. These results suggest that referred pain observed in severe hip osteoarthritis cases may initially triggered by hip joint itself but prolonged referred muscle pain may become a possible generator for triggering and maintaining of mal-pain circuit.

著者

射場 浩介 道家 孝幸 花香 恵 金谷 久美子 阿部 恭久 山下 敏彦

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.31, no.4, pp.203-209, 2016-12-26 (Released:2017-01-27)

参考文献数

20

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We have recently demonstrated that pathological changes leading to increased bone resorption by osteoclast activation are related to the induction of pain–like behavior in ovariectomized (OVX)mice. In addition,we have shown that the skeletal pain accompanying osteoporosis is possibly associated with the acidic microenvironment caused by osteoclast activation under a high bone turnover state. We, therefore, hypothesize that another osteoporosis model mouse might reveal the induction of pain–like behaviors in relation with osteoporotic changes. In this study, we demonstrated that regional osteoporosis of hind limbs induced pain–like behaviors using tailsuspended mice as another osteoporosis model.The hind limbs of tail–suspended mice were unloaded for 2 weeks, during which time the mice revealed significant regional osteoporotic changes in their hind limbs accompanied by osteoclast activation. In addition, these changes were significantly recovered by the resumption of weight bearing on the hind limbs for 4 weeks. Consistent with the pathological changes in the hind limbs, pain–like behaviors in the mice were induced by tail suspension and recovered by the resumption of weight bearing. Moreover, treatment with bisphosphonate significantly prevented the triggering of the regional osteoporosis and pain–like behaviors, and antagonists of the acid–sensing nociceptors, such as transient receptor potential channel vanilloid subfamily member 1 and acid–sensing ion channels, significantly improved the painlike behaviors in the tail–suspended mice.We, therefore, believe that pathologic changes of osteoporosis due to osteo clast activation might be a trigger for the pain–like behaviors in osteoporosis patients.

著者

牛田 享宏 山口 重樹 木村 嘉之 青野 修一

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.33, no.4, pp.257-268, 2018-12-28 (Released:2019-03-29)

参考文献数

4

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Chronic pain is a biological psychosocial pathological condition, which is caused by various elements involved in many ways. Therefore, it is necessary to analyze the disease state from various viewpoints and to treat multimodally. Since there was no standard diagnostic tool for chronic pain so far, it was difficult to develop epidemiological research and development and evaluation of treatment in accordance with specific pathological conditions. Therefore, the IASP proceeded development to add the item of Chronic Pain in ICD–11, which was officially announced from WHO in June 2018. This attempts to classify chronic pain into seven major categories (① chronic primary pain, ② chronic cancer related pain, ③ chronic postoperative and posttraumatic pain, ④ chronic secondary musculoskeletal pain, ⑤ chronic secondary visceral pain, ⑥ chronic neuropathic pain, ⑦ chronic secondary headache and/or orofacial pain) and others.By developing a more realistic method of using this new standard disease name, effective utilization not only in research but also in clinical practice is needed. In addition, this review will also introduce the versions that the Chronic Pain Research Group of the Ministry of Health, Labor and Welfare has been developing. At the same time as disease name classification, it is important to know where and how to treat chronic pain.In 2017, IASP defined the treatment by forming “Task Force on Multimodal Pain Treatment Defines Terms for Chronic Pain Care” in order to unify the names of confused treatment modes. At the same time as disease name classification, it is important to know where and how to treat chronic pain. Also, in the past, IASP has been defining treatment facilities such as Multidisciplinary Pain Center. In addition, this time we will introduce the assessment of O–P factor which is helpful for thinking about what kind of patients and where to receive medical treatment.

著者

坂井 敦 丸山 基世 鈴木 秀典

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.34, no.3, pp.219-227, 2019-09-20 (Released:2019-11-08)

参考文献数

51

被引用文献数

1

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Non–coding RNAs affect various cellular processes through interaction with DNA, RNA and protein. Accordingly, non–coding RNAs, microRNAs and more recently long non–coding RNAs, have been shown to be involved in pain disorders, including neuropathic pain. MicroRNAs inhibit translational step of gene expression and dysregulation of microRNAs underlies the neuropathic pain. On the other hand, lncRNAs regulate diverse steps of gene expression, including epigenetic modulation, transcription, alternative splicing and translation, although a role of lncRNAs in the pain disorders remain poorly understood. Interestingly, a part of non–coding RNAs are released to extracellular space and mediate a cell–cell communication. Extracellular microRNAs are shown to modulate nociceptive transmission. Furthermore, extracellular non–coding RNAs are expected as a specific biomarker for neuronal damage or pain in the blood. In this review, we summarize current insights into non–coding RNA significance in the neuropathic pain.

著者

林 聖子 岡田 薫 川喜田 健司

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.25, no.1, pp.45-53, 2010-03-15 (Released:2013-06-26)

参考文献数

24

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To investigate underlying mechanism of subjective pain ⁄ numbness sensation following ischemia-reperfusion of upper arm, we examined the changes in skin blood flow (SBF) and current perception threshold (CPT). Eighteen healthy volunteers with informed consents were used. A 140 mm wide tourniquet cuff was inflated to 200 mmHg and maintained for 15 min at non-dominant upper arm. SBF was measured by Laser Doppler flow meter before, during and after ischemia at the index finger. Magnitude of the evoked pain ⁄ numbness sensation after ischemia-reperfusion was recorded by VAS with an electric device continuously. CPT was measured by 5, 250, 2000 Hz of sine-waves randomly applied to the index finger. SBF was increased immediately after reperfusion in all the subjects. Pain ⁄ numbness sensation was also evoked after reperfusion in all subjects.But baseline SBF, increased SBF and magnitude of subjective sensation after reperfusion were different among individuals. Correlation between changes of SBF and magnitude of subjective sensation measured by VAS did not show statistical significance. After ischemia-reperfusion, significant increases of CPT were observed in 250 and 2000 Hz (baseline vs. after reperfusion, p<0.01). The sine-wave stimulation of 5, 250 and 2000 Hz were assumed to activate C, A-delta and A-beta fibers, respectively. The production of pain ⁄ numbness sensation was accompanied with the significant increases of CPT at 250 and 2000 Hz after reperfusion. These results suggest the participation of A fibers in the production of pain ⁄ numbness sensation evoked by ischemia-reperfusion.

著者

水谷 みゆき 鈴木 千春 大道 裕介 櫻井 博紀 森元 温子 西原 真理 牛田 亨宏 新井 健一 佐藤 純

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.27, no.3, pp.175-188, 2012-08-10 (Released:2013-02-19)

参考文献数

44

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The effect of hypnotic intervention for the refractory chronic pain patients was examined along with the process of patients' selection and their psychological characteristics. The total 596 visit patients in the first year were statistically examined concerning duration of pain, scores of psychological distress (Hospital Anxiety and Depression Scale) and disability (Pain Disability Assessment Scale) at the initial visit and the treatment outcome at the end of the first year. The duration of chronic pain was significantly related to disability but not to psychological distress at the initial visit. At the end of the first year of multidisciplinary pain treatment, 44% of total patients were under treatment, 19% finished treatment (10% evidently improved and 9% accepted their pain), 12% were referred and 25% dropped out. The group of patients who were evidently improved was not different concerning the duration of pain, but significantly less anxious, less depressed and less disabled at the initial visit than the other groups. Among the 261 patients under treatment, 33 patients (5.6% of total patients) were introduced into individual psychological interventions in consideration of 1) poor outcome in pharmacological and physical treatments, 2) unstable treatment relationship and marked pain behaviors, 3) obvious psychological distress, 4) event-related fluctuations in pain. They were significantly more anxious and depressed at the initial visit, than those who were not introduced to psychological intervention. Multiple bio-psycho-social factors were identified; tender points in 21 patients (by physiotherapist), stressful life events around the onset of pain in 26, serious daily conflicts at present in 30, catastrophizing thinking in 21, repressive thinking in 12, avoidance in 2 and perseverative coping in 6. Many of them did not or partly perceive their somatic tension / discomfort. Multiple factors were considered to inhibit the effect of treatment in those patients. In individual hypnosis, therapeutic conversation, permissive induction and indirect suggestions were employed. Direct suggestions for analgesia were not applied. Among 33 patients, 25 patients experienced hypnotic analgesia during sessions, 14 of whom finished their sessions with the decreased daily pain level or the enhanced effect of medication until the end of the 3rd year. Among them, 5 patients evidently improved (one phantom limb pain and 4 other chronic pain). Hypnosis successfully helped 42% of the patients who had failed to respond to multi disciplinary treatment. The psychosomatic resources in patients need to be more attended and utilized in chronic pain treatment.

著者

河野 崇 横山 正尚

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.28, no.3, pp.177-181, 2013-08-30 (Released:2013-10-03)

参考文献数

8

被引用文献数

1 1

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Some validated methods for assessing pain in laboratory animals are currently available. However, it remains to be determined whether these methods are also applicable for aged animals. Recently, grimace scale (GS) was developed for pain assessment based on facial expressions, and can effective­ly evaluate animal spontaneous pain. In the present study, we investigat­ed that accuracy and reliability of the rat grimace scale (RGS) in aged rats. Six coders were trained with the RGS training manual. Unlabeled 80 facial images of which half were with no pain (baseline), the other half were with pain (2 - 4 h after laparotomy) were randomly assigned and then scored by the coders. A high degree of the reliability was found with an overall intra-class correlation coefficient value of 0.92. The average ac­curacy of pain detection assessed by coders’ dichotomous judgment of “global pain” or “no pain” was sufficiently high with a correct classification rate of 84.6%. Furthermore, a single subcutaneous administration with morphine (1.0 mg/kg) resulted in decrease of RGS at 4 h after laparotomy. These results suggested that RGS is a useful method for assessing spontaneous pain after laparotomy in aged rats.

著者

阿漕 孝治 泉 仁 岡上 裕介 池内 昌彦

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.31, no.4, pp.197-202, 2016-12-26 (Released:2017-01-27)

参考文献数

11

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Knee pain is a major source of disability in patients with knee osteoarthritis (OA). Although the mechanism of OA progression has been well documented, pain pathophysiology is largely unknown. Recent accumulating clinical evidence indicates that subchondral bone marrow lesions (BMLs) detected on MRI in knee OA are strongly associated with intense pain. In this review we describes bone pain in knee osteoarthritis clarified by our basic and clinical studies.In basic studies, we clarified nociceptive phenotype alterations of subchondral bone afferents of the distal femur in mono–iodoacetate (MIA)–induced OA rats. Two different retrograde tracers were separately injected into the knee joint cavity and the subchondral bone to identify synovium and subchondral bone afferents. OA caused an up–regulation of calcitonin gene–related peptide (CGRP) and tyrosine receptor kinase A (TrkA) in both synovium and subchondral bone afferents. CGRP and TrkA expression in subchondral bone afferents gradually increased over 6 weeks. Furthermore, up–regulation of CGRP and TrkA in subchondral bone afferents displayed a strong correlation with the subchondral bone damage score. Up–regulation of CGRP and TrkA in subchondral bone afferents correlated with subchondral bone damage, suggesting that subchondral bone is a therapeutic target, especially in the case of advanced stage knee OA.In clinical studies, we clarified the association of subchondral BMLs with pain in medial compartment knee osteoarthritis. Total BMLs size were significantly correlated with walking pain (Spearman’s r=0.59, p<0.01). As a result of the multi regression analysis, subchondral BMLs became a factor of walking knee pain in the case of advanced stage knee OA (Regression coefficient = 0.75, p<0.01). Subchondral BMLs are potentially therapeutic targets to treat pain associated with subchondral bone in knee osteoarthritis.In conclusion, subchondral bone, in itself, is a therapeutic target, especially in the case of advanced stage knee OA. In particular, BMLs are potentially therapeutic targets to treat joint pain associated with the subchondral bone in OA.

著者

渡辺 リサ 北村 泰子 山田 仁三

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.18, no.3, pp.127-136, 2003

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Neurons in the reticular formation of the brainstem are thought to participate in transmission of nociceptive information. However, the role of the reticular formation for the pain mechanism remained to be disclosed. In the present study, extracellular single-unit activities were recorded from the nucleus reticularis magnocellularis and adjacent areas (RF) elicited by electrical, mechanical and thermal noxious stimuli of the rat sciatic nerve.<br>   Multiple-spikes responding to single electrical stimulation were recorded in the single neuron in RF, which responded to pinch. They were grouped into three types: 1) The latency of Fast type was not over 30 msec, although the intensity of electrical stimulation increased, 2) the latency of Slow type was over 200 msec, although the intensity was low, and 3) Mixed type had components of both Fast type and Slow type. Considering the latency and intensity, Fast type, Slow type and Mixed type received information carried via Aδ-fibers, C-fiber and Aδ- and C-fibers, respectively. In Fast type, Aδ-fibers terminated to the single neuron of lamina V, which axon terminated to the single neuron of RF.Since the diameter of Aδ-fibers was different,multiple spikes were obtained with the gradually increased intensity. In Slow type, the neuron of lamina I received C-fibers and sent information via the several interneurons in laminae III-IV to the neuron of lamina V, which axon terminated to the single neuron of RF. Since the diameter of C-fibers was different, multiple spikes were obtained with the gradually increased intensity. As the above-mentioned manner, in Mixed type, the neuron of lamina V received information from both Aδ- and C-fibers and projected to the single neuron of RF. Neurons with the spontaneous spikes had tendency to be reacted by pinch but not by thermal stimulation. Neurons without the spontaneous spikes were reacted by both pinch and thermal stimulation.<br>   It seems that the single neuron of RF receiving various information from the peripheral nerve activates the ascending reticular activating system and/or descending pain inhibitory system.

著者

石川 理恵 井関 雅子 古賀 理恵 山口 敬介 稲田 英一

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.31, no.3, pp.156-165, 2016-09-30 (Released:2016-10-16)

参考文献数

16

被引用文献数

2

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Introduction: In a retrospective study on patients with zoster–associated pain, we reported the patients were associated with various neuropathic pain components and high VAS values regardless of their disease stages. In the present study, we prospectively followed another group of patients to evaluate those components in each of the stages.    Subjects: The subject group was comprised of 76 patients who first visited our clinic between June 2013 and January 2015 with their onsets of zoster–associat­ed pain within 30 days of the first visits.    Methods: Two neuropathic pain screening questionnaires including the Neuropathic Pain Screening Questionnaire (Japan–Q) and the Pain DETECT Questionnaire (PDQ) were used to track the patients for six months. The questionnaires and Visual Analogue Scale (VAS) evaluations were conducted at each of the acute stage (up to 30 days from the onset), the subacute stage (one to three months) and the chronic stage (the fourth month and after).    Results: Sixty–four patients remained in the subject group throughout the course of the study. The median values of the scores at the acute: subacute: chronic stages were 12 : 4 : 3 for Japan–Q, 15 : 9 : 7 for PDQ and 71.5 : 27.5 : 9.5 for VAS (mm). The numbers of patients with neuropathic pain components more strongly manifested at those stages were 53 (68%) : 14 (18%) : 10 (13%) for Japan–Q scores of 9 or higher and 61 (78%) : 35 (45%) : 21 (27%) for PDQ of 11 or higher. The correlation coefficients between the Japan–Q scores and VAS at the stages were 0.38 : 0.38 : 0.46 while the same between the PDQ scores and VAS were 0.42 : 0.29 : 0.44 indicating moderate correlations at the chronic stage of the pain with both of the questionnaires.    Discussion: While dermatitis and neuritis are common complications of herpes zoster, the fact that the patients experiencing intense pain in the acute phase exhibit neuropathic pain components may suggest the severity of neuritis is more manifested than the other complication. Although the patients diagnosed in our clinic in their acute stages exhibited high scores for the neuropathic pain components and VAS, both declined over time suggesting early intervention by pain specialists may be useful in achieving good therapeutic outcomes, even though spontaneous remission may not be completely ruled out.

著者

Yuzuru Takahashi

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.30, no.3, pp.148-152, 2015-08-10 (Released:2015-08-18)

参考文献数

19

被引用文献数

2

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The speed of change in pain intensity as measured by the visual analog scale (VAS) was investigated in patients with acute low back pain (LBP). Each patient was initially treated with oral nonsteroidal anti–inflammatory drugs (NSAIDs). Clinical outcome was determined by patient self–assessment on the day of the last visit and classified into four groups: healed, improved, marginal, and unidentified. Data were analyzed for 131 cases in the healed (n=55), improved (n=62), and marginal (n=14) groups. VAS values at the first and last visits were denoted as VAS–f and VAS–l, respective­ly. ∆VAS, the speed of change in the VAS value per day was calculat­ed by dividing the change in the VAS value by the number of days elapsed. The initial ∆VAS (∆VAS–i) and the ∆VAS throughout the study (∆VAS–t) were calculated between the first and second visits and between the first and last visits, respective­ly. VAS–f was not relevant to outcome, while VAS–l was strongly cor­related with outcome, as expected. Both ∆VAS–i and ∆VAS–t were significantly correlated with outcome. Patients in the healed and improved groups showed higher ∆VAS–i values as compared with those in the marginal group. A ∆VAS–i over 5 mm/day predicted favorable outcomes. The ∆VAS–i can be regarded as a predictor of outcome in acute LBP. Speedy pain relief should be planned for patients with acute LBP with a low ∆VAS–i to prevent a change to chronic LBP.

著者

河合 隆志 牛田 享宏 井上 真輔 池本 竜則 新井 健一 西原 真理

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.29, no.3, pp.181-189, 2014-08-30 (Released:2014-09-16)

参考文献数

20

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Many patients have neck and back pain, and their standing posture (spinal alignment) is sometimes considered to be one of the factors that contributes to such pain. Thus, it would be useful to evaluate spinal loads in that posture. A method to evaluate individual spinal loads using link segment models made from body mass distributions using DXA (dual–energy X–ray absorptiometry) was developed.   An element was defined as 1.30 × 1.22 cm, and a detailed body mass distribution consisting of 7473 elements was constructed using DXA equipment (QDR4500). The subjects' bodies were divided into cervicofacial (vertex–C7 ⁄ T1), thoracic (C7 ⁄ T1 – T12 ⁄ L1), and lumbar (T12 ⁄ L1 – L4 ⁄ 5) segments. Each mass, M1, M2, and M3, and the center of the masses were calculated. With these parameters and DXA images, each torque, TC7/T1, TT12/L1, and TL4/5, was calculated from the following formulas: TC7/T1 = M1gr1cosθ1, TT12/L1 = M1g (l2cosθ2 + r1cosθ1) + M2gr2cosθ2, and TL4/5 = M1g (l3cosθ3 + l2cosθ2 + r1cosθ1) + M2g (l3cosθ3 + r2cosθ2) + M3gr3cosθ3 (r1, r2, and r3: lengths from the rotation center to each center of mass; l2 and l3: lengths of C7 ⁄ T1 – T12 ⁄ L1 and T12 ⁄ L1 – L4 ⁄ 5; θ1, θ2, and θ3: angles formed between a horizontal line and r1, r2, and r3). In order to reproduce the standing posture on DXA, the standing side was formed by a vacuum cushion for operative position in advance.   The parameters from DXA in the lateral view were as follows. In case 1 (38–year–old man, healthy, 164.0 cm and 55.5 kg), they were M1 = 4.50, M2 = 13.24, M3 = 6.92 kg, TC7/T1 = –0.28, TT12/L1 = –3.80, and TL4/5 = –6.42 Nm (facing right, clockwise: positive). In case 2 (76–year–old man, lumbar spondylosis, 156.9 cm and 59.6 kg), they were M1 = 4.83, M2 = 14.27, M3 = 10.34 kg, TC7/T1 = –1.69, TT12/L1 = –16.1, and TL4/5 = –44.3 Nm. In case 3 (71–year–old woman, lumbar spondylosis, scoliosis, 147.2 cm and 49.0 kg), they were M1 = 4.63, M2 = 11.42, M3 = 5.36 kg, TC7/T1 = –2.53, TT12/L1 = –16.0, and TL4/5 = –27.0 Nm. Torques at L4/5 were 6.9 and 4.2 times greater in cases 2 and 3 than in case 1. Total masses calculated from DXA were 54.5, 59.0, and 47.6 kg, and errors between these and actual weights were –1.8, –1.0, and –2.9%, respectively.   A method for evaluating spinal loads as torques was developed using DXA. In the future, it will be possible to use this method to evaluate factors such as pain and the effect of rehabilitation. The relationships between torques and various scales (such as pain, depression, ADL, and QOL) need to be examined, taking into account age, sex, muscular strength, etc.

著者

長谷川 共美 池本 竜則 井上 雅之 山口 節子 牛田 享宏 柴田 英治 小林 章雄

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.29, no.1, pp.1-8, 2014-03-10 (Released:2014-03-29)

参考文献数

29

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The aim of this study was to investigate the features of overweight or obese individuals with a BMI >25 kg/m2 who complained of low back pain, knee pain, and neck stiffness. The subjects comprised 88 overweight or obese individuals who were divided into a symptomatic group and an asymptomatic group prior to the weight–loss intervention in order to compare several parameters of each group. Symptomatic patients were divided into groups of subjects whose symptoms did or did not improve as a result of the 6–month weight–loss intervention. Changes in the test paramete­rs from before and after the intervention were compared between the two groups. The results revealed no differences in any parameters between the two groups (symptomatic and asymptomatic) at baseline in neck stiffness or low back pain. However, for knee pain, the maximal oxygen uptake (VO2max) was significantly lower in the symptomatic group than in the asymptomatic group (p<0.01). Furthermore, the weight–loss intervention revealed a significant increase in VO2max in the “improved” group compared to the “no change” group (p<0.05). The study results showed that both weight loss and the acquisition of aerobic capacity were important in relieving knee pain in overweight or obese individuals.

著者

播磨 晃宏 高木 博司

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.6, no.2, pp.179-182, 1991-07-31 (Released:2014-06-19)

著者

岡田 弘 三浦 政直 中山 裕人 水間 謙三 川村 隆枝 岡田 一敏 涌澤 玲児

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.7, no.2, pp.149-155, 1992-07-31 (Released:2014-06-19)

著者

池本 竜則 牛田 享宏 谷口 慎一郎 谷 俊一 森尾 一夫 佐々木 俊一 Zinchuk Vadim 田中 茂樹

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.19, no.3, pp.107-112, 2004-07-31 (Released:2014-02-20)

参考文献数

9

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It is widely known that sensation of the pain is derived from sensory-discriminative factor and emotional factor. Especially in chronic pain, emotional factors and psychosocial backgrounds are more likely to contribute for the patients' discomfort. The aim of this study is to investigate how emotional factor of pain participates in intractable pain. We employed fMRI to compare the brain activations occurring in the orthopaedic neuropathic pain patients with allodynia and normal individuals in response to the visual virtual painful experience. During fMRI scanning, a video demonstrating an actual tactile stimulation of the palm and its imitation were shown to participants. In contrast to normal individuals,allodynia patients also displayed activation of the areas reflecting emotions: frontal lobe and anterior cingulate. These findings suggest that brain have important role in the development and maintaining of peripheral originated chronic painful condition.

著者

池本 竜則 牛田 享宏 谷口 慎一郎 谷 俊一 森尾 一夫 佐々木 俊一 田中 茂樹

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.21, no.3, pp.117-125, 2006-08-20 (Released:2013-10-24)

参考文献数

36

被引用文献数

2 1

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Using functional magnetic resonance imaging (FMRI) technology, we investigated the difference of pain related brain cortical activation derived from noxious stimulation to the skin and muscular tissue. Ten healthy volunteers who have no history of brain vascular disease were enrolled in this study. A cutaneouos pain was provoked by isotonic (0.9%) saline injection into intradermal space on right lower leg through 24G plastic catheter, and a muscle pain was provoked by hypertonic (3%) saline injection into right tibialis anterior muscle. We used event-related FMRI to measure brain activity during each injection. Visual analogue scale (VAS) was used to quantify pain intensity and unpleasantness, and pain quality was assessed with several verbal descriptions. Results: Pain unpleasantness rating was higher in the muscle pain compared to the cutaneous pain,despite the same pain intensity rating. The cutaneous pain had more acute pain onset than the muscle pain. Pain duration after stimulation was short in the cutaneous pain, but long in the muscle pain. The extent of the painful region tended to be larger with the muscle pain, but there was no statistical significance. Evoked FMRI response from the cutaneous pain showed distinct brain activation in the inferior and superior parietal cortex (BA: Brodmann area 5/7/40), primary and secondary somatosensory cortex (S1 & S2), insula, supplementary motor area (SMA, BA6), posterior cingulate cortex and cerebellum. On the other hand, FMRI response from muscle pain showed distinct brain activation mainly in the contralateral insula. These results suggest that the parietal lobe including the S1 is the essential area for cognition of sharp and well-localized pain conditions such as cutaneous pain, and may not be essential for cognition of diffuse pain derived from muscular tissue.

著者

池本 竜則 牛田 享宏 谷口 慎一郎 谷 俊一 森尾 一夫 佐々木 俊一 田中 茂樹

出版者

日本疼痛学会

雑誌

PAIN RESEARCH (ISSN:09158588)

巻号頁・発行日

vol.20, no.3, pp.111-115, 2005-08-26 (Released:2014-01-16)

参考文献数

9

被引用文献数

1 3

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We employed the functional MRI (fMRI) to investigate the changes of brain activation after reducing of capsaicin-induced heat hyperalgesia. Eight healthy volunteers who have no history of brain vascular disease were enrolled in this study. Capsaicin-induced heat hyperalgesia was developed by topical application of 2% capsaicin cream to anterior surface of left forearm. First fMRI time series were taken an hour after the application of capsaicin and second fMRI time series were taken an hour after medication (Loxoprofen Na: 120 mg). As for the pain task, 45°C wet cotton was put on the region where the heat hyperalgesia was evoked by capsaicin cream. Results of first fMRI time series showed distinct activation in the thalamus, anterior cingulate cortex, supplementary motor area, and prefrontal cortex. An hour after medication, though heat hyperalgesia still remained, all participants reported improvement of pain discomfort (VAS 4.7 to 2.5). Second series fMRI showed activation only in the thalamus. These results suggest that deactivated areas (anterior cingulate, etc.) observed after medication might be involved mainly in the pain related discomfort.