- Email: [email protected]
S271 EPIDEMIOLOGICAL DATA OF A NATIONWIDE SURVEY ABOUT PHANTOM PHENOMENA AFTER AMPUTATION OF A LIMB
242
POSTER SESSIONS / European Journal of Pain Supplements 5 (2011) 15–295
S269 ILLUSORY HAND OWNERSHIP IN UPPER LIMB AMPUTEES SUFFERING FROM PHANTOM PAIN R. Bekrater-Bodmann *, J. Foell, M. Diers, S. Kamping, M. Rance, P. Yilmaz, J. Trojan, H. Flor. Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health; Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany Background and Aims: Phantom limb pain (PLP) is a common occurrence in upper limb amputees, often accompanied by several distortions of the phantom limb, such as stiffness, unusual postural features or telescoping. Previous studies indicate that amputees can be induced to perceive an artificial limb as their own. However, there is evidence of a trait to perceive illusory limb ownership, which might depend on inter-individual capabilities to link external stimulation and internal body representation. This study aimed at underlying determinants in amputees suffering from PLP. Methods: We induced the so-called rubber hand illusion (RHI) in 15 upper limb amputees suffering from PLP, and related their responses to their phantom experience. We compared these data with responses yielded in an amputee control group without PLP. Results: We found a relationship between the vividness of illusory limb ownership and perceptual features of the phantom limb. Alterations in perception of the phantom limb seem to be associated with fewer RHI sensations. However, the impact of PLP on illusory limb ownership is much more sophisticated. Conclusions: We showed that perceived features of the phantom limb are associated with the ability to experience an artificial limb as one’s own. This might have important implications for prospective prostheses, since the capability for ownership experience might be a requirement for successful prosthesis use. Funding: This research was supported by the PHANTOMMIND advanced grant of the European Research Council (FP7/2007–2013)/ ERC Grant Agreement No. 230249. Disclosure: None declared
S270 CORTICAL EFFECTS AND MULTISENSORY INTEGRATION IN MIRROR THERAPY FOR PHANTOM LIMB PAIN J. Foell, R. Bekrater-Bodmann, M. Diers *, H. Flor. Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health; Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany Background and Aims: It has been shown that chronic phantom limb pain (PLP) can be alleviated by creating a controllable visual representation of the lost limb. This method, however, has never been proven to work on a neuronal level. Our goal was to objectify treatment effectiveness by relating subjective pain alleviation to changes in cortical reorganization and to investigate determining factors for treatment efficacy. Methods: Eleven chronic PLP patients performed a four-week mirror training and gave daily pain reports. Patients were asked to perform movement tasks with their intact hand in front of a mirror and to relate the observed movements to their phantom limb. We examined these patients before and after training in using fMRI: Here, patients repeated the mirror tasks and performed a lippursing task to determine altered cortical organization. Results: Patients on average reported significant pain alleviation (p < 0.05) and an increased feeling of relatedness to the hand displayed in the mirror. However, there was a large range in response to treatment, which could in part be explained by traits such as a telescopic distortion of the phantom. The amount of pain alleviation was correlated with beneficial changes in somatosensory cortex and with activational alterations in the inferior parietal cortex. Conclusions: Mirror treatment creates effects on the subjective as well as neuronal level. Treatment benefit, however, seems to be related to characteristics of phantom perception.
Funding: This research was supported by the PHANTOMMIND advanced grant of the European Research Council (FP7/2007–2013)/ ERC Grant Agreement No. 230249. Disclosure: None declared
S271 EPIDEMIOLOGICAL DATA OF A NATIONWIDE SURVEY ABOUT PHANTOM PHENOMENA AFTER AMPUTATION OF A LIMB P. Yilmaz *, M. Diers, R. Bekrater-Bodmann, J. Foell, S. Kamping, M. Rance, J. Trojan, H. Flor. Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany Background and Aims: In a nationwide survey the incidence of phantom limb pain (PLP) and other phantom phenomena were assessed. Methods: A total of 23000 questionnaires were sent to persons after an amputation. About 12% of the amputees fully completed the questionnaires and gave their approval for data acquisition. The questionnaire contained 53 items and contained a detailed assessment of phantom phenomena involving drawings. There were different versions for arm and leg amputees. Results: Mean age of the patients was 64.6 years (range 18–98), 80% were male. 60.3% of the patients had phantom limb pain (PLP), 14.6% had PLP in the past. The mean PLP intensity was 5.7 (scale 0 – no pain, 10 – strongest imaginable pain). 15.4% of the patients reported referred sensations. We also report other phantom phenomena such as awareness of the phantom, phantom sensations or telescoping as well as stump phenomena and prosthesis use and their correlation with PLP. Conclusion: There is a high prevalence for PLP in persons with limb loss. PLP is associated with other phantom phenomena. Further research is needed for a better understanding of the causes of PLP to provide differential intervention strategies. Acknowledgement: This research was supported by the PHANTOMMIND advanced grant of the European Research Council (FP7/2007–2013)/ERC Grant Agreement No. 230249. Disclosure: None declared
S272 NERVE GROWTH FACTOR-MEDIATED NEURONAL PLASTICITY IN SPINAL CORD CONTRIBUTES TO NEONATAL MATERNAL SEPARATION-INDUCED VISCERAL HYPERSENSITIVITY IN RATS Z.-X. Bian1 *, S.W. Tsang1 , J. Wu2 , M. Zhou1 . 1 Hong Kong Baptist University, 2 The Chinese University of Hong Kong, Hong Kong, Hong Kong S.A.R. Background and Aims: This study aimed to investigate whether nerve growth factor (NGF)-mediated neuronal plasticity is involved in neonatal maternal separation (NMS)-induced visceral hypersensitivity in adult rats, and whether NGF antagonist can attenuate or block such development. Methods: Rats subjected to NMS were developed with visceral hyperalgesia at age of 8 weeks. And NGF antagonist were applied too to see whether it can affect. Results: The thresholds for visceral pain among these NMS rats were remarkably lowered than the normal handling (NH) rats; however, the expression levels of NGF, c-fos, calcitonin gene-related peptide (CGRP), Substance P, and tyrosine kinases A (TrkA), were notably elevated in lumbosacral spinal cord and/or dorsal root ganglion (DRG) when comparing to those of the NH rats. Further as intra-peritoneal administration of NGF (10 ml at 1 mg/kg/day) was given to NH rats during neonatal period, effects that comparable to NMS induction were observed in the adulthood of those NH rats. In contrast, when NMS rats were treated with NGF antagonist K252a (10 ml/day from postnatal days 2 to 14), which acts against tyrosine kinases, the neonatal stress-induced lowered visceral pain threshold, neuronal activation, specifically NGF and neuro-peptide production, were significantly attenuated.
POSTER SESSIONS / European Journal of Pain Supplements 5 (2011) 15–295
S269 ILLUSORY HAND OWNERSHIP IN UPPER LIMB AMPUTEES SUFFERING FROM PHANTOM PAIN R. Bekrater-Bodmann *, J. Foell, M. Diers, S. Kamping, M. Rance, P. Yilmaz, J. Trojan, H. Flor. Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health; Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany Background and Aims: Phantom limb pain (PLP) is a common occurrence in upper limb amputees, often accompanied by several distortions of the phantom limb, such as stiffness, unusual postural features or telescoping. Previous studies indicate that amputees can be induced to perceive an artificial limb as their own. However, there is evidence of a trait to perceive illusory limb ownership, which might depend on inter-individual capabilities to link external stimulation and internal body representation. This study aimed at underlying determinants in amputees suffering from PLP. Methods: We induced the so-called rubber hand illusion (RHI) in 15 upper limb amputees suffering from PLP, and related their responses to their phantom experience. We compared these data with responses yielded in an amputee control group without PLP. Results: We found a relationship between the vividness of illusory limb ownership and perceptual features of the phantom limb. Alterations in perception of the phantom limb seem to be associated with fewer RHI sensations. However, the impact of PLP on illusory limb ownership is much more sophisticated. Conclusions: We showed that perceived features of the phantom limb are associated with the ability to experience an artificial limb as one’s own. This might have important implications for prospective prostheses, since the capability for ownership experience might be a requirement for successful prosthesis use. Funding: This research was supported by the PHANTOMMIND advanced grant of the European Research Council (FP7/2007–2013)/ ERC Grant Agreement No. 230249. Disclosure: None declared
S270 CORTICAL EFFECTS AND MULTISENSORY INTEGRATION IN MIRROR THERAPY FOR PHANTOM LIMB PAIN J. Foell, R. Bekrater-Bodmann, M. Diers *, H. Flor. Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health; Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany Background and Aims: It has been shown that chronic phantom limb pain (PLP) can be alleviated by creating a controllable visual representation of the lost limb. This method, however, has never been proven to work on a neuronal level. Our goal was to objectify treatment effectiveness by relating subjective pain alleviation to changes in cortical reorganization and to investigate determining factors for treatment efficacy. Methods: Eleven chronic PLP patients performed a four-week mirror training and gave daily pain reports. Patients were asked to perform movement tasks with their intact hand in front of a mirror and to relate the observed movements to their phantom limb. We examined these patients before and after training in using fMRI: Here, patients repeated the mirror tasks and performed a lippursing task to determine altered cortical organization. Results: Patients on average reported significant pain alleviation (p < 0.05) and an increased feeling of relatedness to the hand displayed in the mirror. However, there was a large range in response to treatment, which could in part be explained by traits such as a telescopic distortion of the phantom. The amount of pain alleviation was correlated with beneficial changes in somatosensory cortex and with activational alterations in the inferior parietal cortex. Conclusions: Mirror treatment creates effects on the subjective as well as neuronal level. Treatment benefit, however, seems to be related to characteristics of phantom perception.
Funding: This research was supported by the PHANTOMMIND advanced grant of the European Research Council (FP7/2007–2013)/ ERC Grant Agreement No. 230249. Disclosure: None declared
S271 EPIDEMIOLOGICAL DATA OF A NATIONWIDE SURVEY ABOUT PHANTOM PHENOMENA AFTER AMPUTATION OF A LIMB P. Yilmaz *, M. Diers, R. Bekrater-Bodmann, J. Foell, S. Kamping, M. Rance, J. Trojan, H. Flor. Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany Background and Aims: In a nationwide survey the incidence of phantom limb pain (PLP) and other phantom phenomena were assessed. Methods: A total of 23000 questionnaires were sent to persons after an amputation. About 12% of the amputees fully completed the questionnaires and gave their approval for data acquisition. The questionnaire contained 53 items and contained a detailed assessment of phantom phenomena involving drawings. There were different versions for arm and leg amputees. Results: Mean age of the patients was 64.6 years (range 18–98), 80% were male. 60.3% of the patients had phantom limb pain (PLP), 14.6% had PLP in the past. The mean PLP intensity was 5.7 (scale 0 – no pain, 10 – strongest imaginable pain). 15.4% of the patients reported referred sensations. We also report other phantom phenomena such as awareness of the phantom, phantom sensations or telescoping as well as stump phenomena and prosthesis use and their correlation with PLP. Conclusion: There is a high prevalence for PLP in persons with limb loss. PLP is associated with other phantom phenomena. Further research is needed for a better understanding of the causes of PLP to provide differential intervention strategies. Acknowledgement: This research was supported by the PHANTOMMIND advanced grant of the European Research Council (FP7/2007–2013)/ERC Grant Agreement No. 230249. Disclosure: None declared
S272 NERVE GROWTH FACTOR-MEDIATED NEURONAL PLASTICITY IN SPINAL CORD CONTRIBUTES TO NEONATAL MATERNAL SEPARATION-INDUCED VISCERAL HYPERSENSITIVITY IN RATS Z.-X. Bian1 *, S.W. Tsang1 , J. Wu2 , M. Zhou1 . 1 Hong Kong Baptist University, 2 The Chinese University of Hong Kong, Hong Kong, Hong Kong S.A.R. Background and Aims: This study aimed to investigate whether nerve growth factor (NGF)-mediated neuronal plasticity is involved in neonatal maternal separation (NMS)-induced visceral hypersensitivity in adult rats, and whether NGF antagonist can attenuate or block such development. Methods: Rats subjected to NMS were developed with visceral hyperalgesia at age of 8 weeks. And NGF antagonist were applied too to see whether it can affect. Results: The thresholds for visceral pain among these NMS rats were remarkably lowered than the normal handling (NH) rats; however, the expression levels of NGF, c-fos, calcitonin gene-related peptide (CGRP), Substance P, and tyrosine kinases A (TrkA), were notably elevated in lumbosacral spinal cord and/or dorsal root ganglion (DRG) when comparing to those of the NH rats. Further as intra-peritoneal administration of NGF (10 ml at 1 mg/kg/day) was given to NH rats during neonatal period, effects that comparable to NMS induction were observed in the adulthood of those NH rats. In contrast, when NMS rats were treated with NGF antagonist K252a (10 ml/day from postnatal days 2 to 14), which acts against tyrosine kinases, the neonatal stress-induced lowered visceral pain threshold, neuronal activation, specifically NGF and neuro-peptide production, were significantly attenuated.