ReLiPh: rehabilitation for lower limb with phantom pain

O membro fantasma ou sensação fantasma, ao longo dos anos, têm se destacado por ser originada de diferentes causas. Pesquisas e estudos mostram que, após uma amputação, na maioria dos casos, experienciam a sensação de membro fantasma e em muitos desses casos dolorosos. A presente tese baseia-se em uma pequena parte deste amplo tópico. Baseada na terapia de espelho usada na reabilitação e tratamento da dor fantasma. Ao longo do projeto, nós estudamos quais são os componentes mais relevantes para a reorganização/reestruturação, a fim de eliminar os sintomas negativos e futuros distúrbios/perturbações. Associada na relação do cérebro com o corpo, ou seja, as imagens formadas pelo cérebro em relação ao corpo físico desempenhando um papel crucial na relação do membro fantasma e da dor no membro fantasma, bem como no processo de cura e tratamento através de exercícios e no relacionamento da imagem que o cérebro tem do corpo físico. Esta dissertação tem como objetivo na construção de uma nova abordagem tecnológica, baseando-se nos princípios e critérios utilizados na terapia de espelho. A metodologia assenta na criação de um ambiente de realidade virtual controlado por um dispositivo que captura a atividade muscular em tempo real. Implementado num jogo baseado em movimentos/exercícios simples e naturais, sem uso de força ou esforço. Os elevados resultados verificados e testados, em indivíduos saudáveis e em um estudo de caso, na redução da dor fantasma, gerando um interesse e motivação, além de um melhor senso de presença e foco durante o seu uso. Concluindo, o projeto abre novas direções futuras de como novas abordagens tecnológicas podem ser usados nas pesquisas médicas na área do membro e na dor fantasma, em ambientes controlados e contextualizados. Melhorando a eficácia e eficiência, garantindo uma maior flexibilidade nos diferentes casos de amputação.The phantom limb or phantom sensation, over the years, has stood out being originated from different causes. Research and studies show that after an amputation, in most cases, they experience the sensation of a phantom limb and in many of those painful feelings. This thesis is based on a small part of this wide topic. Based on the mirror therapy used in rehabilitation and treatment for phantom pain. Throughout the project, we study what are the most relevant components to reorganization/restructuring in order to eliminate negative symptoms and future disturbances. Moreover it is established in the relationship of the brain with the body, that the images formed by the brain in relation to the physical body play a crucial role in the relationship with the phantom limb and phantom limb pain, as well as in the process of healing and treatment throughout exercises and the relationship of the image that the brain has to the physical body. This dissertation aims to build a new technological approach, based on the principles and criteria used in mirror therapy. The methodology is based on the creation of a virtual reality environment controlled by a device which captures the muscle activity in real time. Implemented in a game based on natural and simple effortless exercises without the use of strength. The high results verified and tested, in healthy subjects and in a case study, to reduce phantom pain, generating an interest and motivation, as well as a better sense of presence and focus during its use. In conclusion, the project opens up new future directions of how new technological approaches can be used in medical research in the field of phantom limbs and in phantom pain, in a controlled and contextualized environments and/or movements. Improving effectiveness and efficiency ensuring greater flexibility in different cases of amputation

Visualizing the Unseen: Illustrating and Documenting Phantom Limb Sensations and Phantom Limb Pain With C.A.L.A.

Currently, there is neither a standardized mode for the documentation of phantom sensations and phantom limb pain, nor for their visualization as perceived by patients. We have therefore created a tool that allows for both, as well as for the quantification of the patient's visible and invisible body image. A first version provides the principal functions: (1) Adapting a 3D avatar for self-identification of the patient; (2) modeling the shape of the phantom limb; (3) adjusting the position of the phantom limb; (4) drawing pain and cramps directly onto the avatar; and (5) quantifying their respective intensities. Our tool (C.A.L.A.) was evaluated with 33 occupational therapists, physiotherapists, and other medical staff. Participants were presented with two cases in which the appearance and the position of the phantom had to be modeled and pain and cramps had to be drawn. The usability of the software was evaluated using the System Usability Scale and its functional range was evaluated using a self-developed questionnaire and semi-structured interview. In addition, our tool was evaluated on 22 patients with limb amputations. For each patient, body image as well as phantom sensation and pain were modeled to evaluate the software's functional scope. The accuracy of the created body image was evaluated using a self-developed questionnaire and semi-structured interview. Additionally, pain sensation was assessed using the SF-McGill Pain Questionnaire. The System Usability Scale reached a level of 81%, indicating high usability. Observing the participants, though, identified several operational difficulties. While the provided functions were considered useful by most participants, the semi-structured interviews revealed the need for an improved pain documentation component. In conclusion, our tool allows for an accurate visualization of phantom limbs and phantom limb sensations. It can be used as both a descriptive and quantitative documentation tool for analyzing and monitoring phantom limbs. Thus, it can help to bridge the gap between the therapist's conception and the patient's perception. Based on the collected requirements, an improved version with extended functionality will be developed

Phantom limb pain, cortical reorganization and the therapeutic effect of mental imagery

Using functional MRI (fMRI) we investigated 13 upper limb amputees with phantom limb pain (PLP) during hand and lip movement, before and after intensive 6-week training in mental imagery. Prior to training, activation elicited during lip purse showed evidence of cortical reorganization of motor (M1) and somatosensory (S1) cortices, expanding from lip area to hand area, which correlated with pain scores. In addition, during imagined movement of the phantom hand, and executed movement of the intact hand, group maps demonstrated activation not only in bilateral M1 and S1 hand area, but also lip area, showing a two-way process of reorganization. In healthy participants, activation during lip purse and imagined and executed movement of the non-dominant hand was confined to the respective cortical representation areas only. Following training, patients reported a significant reduction in intensity and unpleasantness of constant pain and exacerbations, with a corresponding elimination of cortical reorganization. Post hoc analyses showed that intensity of constant pain, but not exacerbations, correlated with reduction in cortical reorganization. The results of this study add to our current understanding of the pathophysiology of PLP, underlining the reversibility of neuroplastic changes in this patient population while offering a novel, simple method of pain relief

Altered bodily perceptions in chronic neuropathic pain conditions and implications for treatment using immersive virtual reality

Chronic neuropathic pain is highly disabling and difficult to treat and manage. Patients with such conditions often report altered bodily perceptions that are thought to be associated with maladaptive structural and functional alterations in the somatosensory cortex. Manipulating these altered perceptions using body illusions in virtual reality is being investigated and may have positive clinical implications for the treatment of these conditions. Here, we have conducted a narrative review of the evidence for the types of bodily distortions associated with a variety of peripheral and central neuropathic pain conditions. In addition, we summarize the experimental and clinical studies that have explored embodiment and body transformation illusions in immersive virtual reality for neuropathic pain relief, which are thought to target these maladaptive changes, as well as suggesting directions for future research

Evaluation of a prototype tool for communicating body perception disturbances in complex regional pain syndrome

Patients with Complex Regional Pain Syndrome (CRPS) experience distressing changes in body perception. However representing body perception is a challenge. A digital media tool for communicating body perception disturbances was developed. A proof of concept study evaluating the acceptability of the application for patients to communicate their body perception is reported in this methods paper. Thirteen CRPS participants admitted to a 2-week inpatient rehabilitation program used the application in a consultation with a research nurse. Audio recordings were made of the process and a structured questionnaire was administered to capture experiences of using the tool. Participants produced powerful images of disturbances in their body perception. All reported the tool acceptable for communicating their body perception. Participants described the positive impact of now seeing an image they had previously only imagined and could now convey to others. The application has provided a novel way for communicating perceptions that are otherwise difficult to convey

Changes in Sensorimotor Cortical Activation in Children Using Prostheses and Prosthetic Simulators

This study aimed to examine the neural responses of children using prostheses and prosthetic simulators to better elucidate the emulation abilities of the simulators. We utilized functional near-infrared spectroscopy (fNIRS) to evaluate the neural response in five children with a congenital upper limb reduction (ULR) using a body-powered prosthesis to complete a 60 s gross motor dexterity task. The ULR group was matched with five typically developing children (TD) using their non-preferred hand and a prosthetic simulator on the same hand. The ULR group had lower activation within the primary motor cortex (M1) and supplementary motor area (SMA) compared to the TD group, but nonsignificant differences in the primary somatosensory area (S1). Compared to using their non-preferred hand, the TD group exhibited significantly higher action in S1 when using the simulator, but nonsignificant differences in M1 and SMA. The non-significant differences in S1 activation between groups and the increased activation evoked by the simulator’s use may suggest rapid changes in feedback prioritization during tool use. We suggest that prosthetic simulators may elicit increased reliance on proprioceptive and tactile feedback during motor tasks. This knowledge may help to develop future prosthesis rehabilitative training or the improvement of tool-based skills

Artificial limb representation in amputees

The human brain contains multiple hand-selective areas, in both the sensorimotor and visual systems. Could our brain repurpose neural resources, originally developed for supporting hand function, to represent and control artificial limbs? We studied individuals with congenital or acquired hand-loss (hereafter one-handers) using functional MRI. We show that the more one-handers use an artificial limb (prosthesis) in their everyday life, the stronger visual hand-selective areas in the lateral occipitotemporal cortex respond to prosthesis images. This was found even when one-handers were presented with images of active prostheses that share the functionality of the hand but not necessarily its visual features (e.g. a \u27hook\u27 prosthesis). Further, we show that daily prosthesis usage determines large-scale inter-network communication across hand-selective areas. This was demonstrated by increased resting state functional connectivity between visual and sensorimotor hand-selective areas, proportional to the intensiveness of everyday prosthesis usage. Further analysis revealed a 3-fold coupling between prosthesis activity, visuomotor connectivity and usage, suggesting a possible role for the motor system in shaping use-dependent representation in visual hand-selective areas, and/or vice versa. Moreover, able-bodied control participants who routinely observe prosthesis usage (albeit less intensively than the prosthesis users) showed significantly weaker associations between degree of prosthesis observation and visual cortex activity or connectivity. Together, our findings suggest that altered daily motor behaviour facilitates prosthesis-related visual processing and shapes communication across hand-selective areas. This neurophysiological substrate for prosthesis embodiment may inspire rehabilitation approaches to improve usage of existing substitutionary devices and aid implementation of future assistive and augmentative technologies