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Concept: Mirror box

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PURPOSE: The purposes of this descriptive study were (a) to identify the relative frequencies of a priori categories of phantom limb pain (PLP) quality descriptors reported by Mid-Southerners with limb loss, (b) to analyze their descriptions for emerging categories of PLP, and © to identify the relative frequencies of the emerging categories. DESIGN: This cross-sectional descriptive verbal survey assessed PLP descriptors. A content analyses determined relative frequencies of a priori PLP descriptors as well as emerging categories that were identified. FINDINGS: The most common a priori PLP quality descriptors reported by 52 amputees with PLP were intermittent, tingling/needles/numb, sharp, cramping, burning, and stabbing. The most common emerging categories reported were pain compared to illness/injury, electrical cyclical, and manipulated/positional. CONCLUSION: The detailed descriptions of PLP provide insight into the vivid experiences of PLP. CLINICAL RELEVANCE: Rehabilitation nurses can use this information with PLP assessment, patient teaching, and counseling.

Concepts: Amputation, Proprioception, Phantom limb, Phantom pain, Illusion, Mirror box, Vilayanur S. Ramachandran, Cortical homunculus

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The clinical use of mirror visual feedback was initially introduced to alleviate phantom pain by restoring motor function through plastic changes in the human primary motor cortex. It is a promising novel technique that gives a new perspective to neurological rehabilitation. Using this therapy, the mirror neuron system is activated and decrease the activity of those systems that perceive protopathic pain, making somatosensory cortex reorganization possible. This paper reports the results of the mirror therapy in three patients with phantom limb pain after recent lower limb amputation, showing its analgesic effects and its benefits as a comprehensive rehabilitation instrument for lower limb amputee geriatric patients.

Concepts: Medicine, Syndromes, Pain, Amputation, Proprioception, Phantom limb, Phantom pain, Mirror box

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We characterized the effect of virtual visual feedback (VVF) on supernumerary phantom limb pain (SPLP) in a patient with high cervical cord injury. The subject was a 22-year-old man diagnosed with complete spinal cord injury (level C2) approximately 5 years ago. We applied the ABA'B' single-case design and set phases B and B' as intervention phases for comparison. SPLP significantly improved in comparison of phase A with phase B and phase A with phase B'. We suggest that VVF reduces SPLP and the effect lasts after VVF.

Concepts: Spinal cord, Amputation, Spinal cord injury, Proprioception, Audio feedback, Phantom limb, Phantom pain, Mirror box

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Postamputation pain (PAP) is highly prevalent after limb amputation but remains an extremely challenging pain condition to treat. A large part of its intractability stems from the myriad pathophysiological mechanisms. A state-of-art understanding of the pathophysiologic basis underlying postamputation phenomena can be broadly categorized in terms of supraspinal, spinal, and peripheral mechanisms. Supraspinal mechanisms involve somatosensory cortical reorganization of the area representing the deafferentated limb and are predominant in phantom limb pain and phantom sensations. Spinal reorganization in the dorsal horn occurs after deafferentataion from a peripheral nerve injury. Peripherally, axonal nerve damage initiates inflammation, regenerative sprouting, and increased “ectopic” afferent input which is thought by many to be the predominant mechanism involved in residual limb pain or neuroma pain, but may also contribute to phantom phenomena. To optimize treatment outcomes, therapy should be individually tailored and mechanism based. Treatment modalities include injection therapy, pharmacotherapy, complementary and alternative therapy, surgical therapy, and interventions aimed at prevention. Unfortunately, there is a lack of high quality clinical trials to support most of these treatments. Most of the randomized controlled trials in PAP have evaluated medications, with a trend for short-term Efficacy noted for ketamine and opioids. Evidence for peripheral injection therapy with botulinum toxin and pulsed radiofrequency for residual limb pain is limited to very small trials and case series. Mirror therapy is a safe and cost-effective alternative treatment modality for PAP. Neuromodulation using implanted motor cortex stimulation has shown a trend toward effectiveness for refractory phantom limb pain, though the evidence is largely anecdotal. Studies that aim to prevent PA P using epidural and perineural catheters have yielded inconsistent results, though there may be some benefit for epidural prevention when the infusions are started more than 24 hours preoperatively and compared with nonoptimized alternatives. Further investigation into the mechanisms responsible for and the factors associated with the development of PAP is needed to provide an evidence-based foundation to guide current and future treatment approaches.

Concepts: Pharmacology, Randomized controlled trial, Alternative medicine, Amputation, Proprioception, Phantom limb, Phantom pain, Mirror box

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Following amputation, individuals ubiquitously report experiencing lingering sensations of their missing limb. While phantom sensations can be innocuous, they are often manifested as painful. Phantom limb pain (PLP) is notorious for being difficult to monitor and treat. A major challenge in PLP management is the difficulty in assessing PLP symptoms, given the physical absence of the affected body part. Here, we offer a means of quantifying chronic PLP by harnessing the known ability of amputees to voluntarily move their phantom limbs. Upper-limb amputees suffering from chronic PLP performed a simple finger-tapping task with their phantom hand. We confirm that amputees suffering from worse chronic PLP had worse motor control over their phantom hand. We further demonstrate that task performance was consistent over weeks and did not relate to transient PLP or non-painful phantom sensations. Finally, we explore the neural basis of these behavioural correlates of PLP. Using neuroimaging, we reveal that slower phantom hand movements were coupled with stronger activity in the primary sensorimotor phantom hand cortex, previously shown to associate with chronic PLP. By demonstrating a specific link between phantom hand motor control and chronic PLP, our findings open up new avenues for PLP management and improvement of existing PLP treatments.

Concepts: Neuroscience, Pain, Amputation, Suffering, Proprioception, Phantom limb, Phantom pain, Mirror box

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Previous work showed the existence of changes in the topographic organization within the somatosensory cortex (SI) in amputees with phantom limb pain, however, the link between nonpainful phantom sensations such as cramping or tingling or the percept of the limb and cortical changes is less clear. We used functional magnetic resonance imaging (fMRI) in a highly selective group of limb amputees who experienced inducible and reproducible nonpainful phantom sensations. A standardized procedure was used to locate body sites eliciting phantom sensations in each amputee. Selected body sites that could systematically evoke phantom sensations were stimulated using electrical pulses in order to induce phasic phantom sensations. Homologous body parts were also stimulated in a group of matched controls. Activations related to evoked phantom sensations were found bilaterally in SI and the intraparietal sulci (IPS), which significantly correlated with the intensity of evoked phantom sensations. In addition, we found differences in intra- and interhemispheric interaction between amputees and controls during evoked phantom sensations. We assume that phantom sensations might be associated with a functional decoupling between bilateral SI and IPS, possibly resulting from transcallosal reorganization mechanisms following amputation.

Concepts: Brain, Magnetic resonance imaging, Amputation, Proprioception, Phantom limb, Phantom pain, Mirror box, Phantom eye syndrome

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Illustrations of phantom limbs are intriguing as they depict an invisible perception. But such illustrations are also important: they provide a form of objectivity to phenomena, which particularly in the past, have often stretched credulity. Acknowledging the paradox of using images to reveal an absent though sensate body part, depictions of phantom limbs are discussed from the neurological perspective, starting with medieval pictures that showed the miraculous restoration of limbs, and which possibly represented pictorial metaphors for a phantom limb. Centuries later, phantom limbs-whether resulting from amputation or deafferentation-became illustrated, and some reasons for their illustration are considered. Although often depicted by others, the most precise and perhaps revealing illustrations of these phantoms have been those made when patients guide the artist, or draw the phantom themselves. In the case of phantom pains, the painful component too is sometimes illustrated, again, as with the miraculous, in metaphorical terms. More recently, depictions of phantoms have also been revealing in studies of some underlying mechanisms of phantom phenomena, notably in demonstrating novel patterns of referred sensations after amputation and attributable to cortical plasticity. Mention is made of photographs of phantom hands visualized using a mirror box, such visualization recalling full circle the miraculous restoration of limbs pictured in the past. The nature of the outline of the phantom is included in a discussion of demarcation of an invisible body part, before concluding that images of phantom limbs provide an invaluable background to understanding and studying these remarkable sensory phenomena.

Concepts: Pain, IMAGE, Graphic design, Proprioception, Phantom limb, Phantom pain, Drawing, Mirror box

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Post amputation, the complication of phantom limb pain (PLP) is prevalent and difficult to manage. This study aimed to determine whether it was feasible and acceptable to undertake a definitive multicentred randomised controlled trial assessing the effectiveness of acupuncture for treating lower limb amputees with PLP.

Concepts: Syndromes, Amputation, Proprioception, Phantom limb, Phantom pain, Mirror box, Vilayanur S. Ramachandran, Cortical homunculus

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Despite the multiple available pharmacological and behavioral therapies for the management of chronic phantom limb pain (PLP) in lower limb amputees, treatment for this condition is still a major challenge and the results are mixed. Given that PLP is associated with maladaptive brain plasticity, interventions that promote cortical reorganization such as non-invasive brain stimulation and behavioral methods including transcranial direct current stimulation (tDCS) and mirror therapy (MT), respectively, may prove to be beneficial to control pain in PLP. Due to its complementary effects, a combination of tDCS and MT may result in synergistic effects in PLP.

Concepts: Medicine, Clinical trial, Amputation, Proprioception, Phantom limb, Phantom pain, Mirror box, Vilayanur S. Ramachandran