Distinct patterns of metabolic motor cortex activity for phantom and residual limb pain in people with amputations: A functional near-infrared spectroscopy study.

BACKGROUND: Phantom pain limb (PLP) has gained more attention due to the large number of people with amputations around the world and growing knowledge of the pain process, although its mechanisms are not completely understood. OBJECTIVES: The aim of this study was to understand, in patients with amputations, the association between PLP and residual limb pain (RLP), and the brain metabolic response in cortical motor circuits, using functional near-infrared spectroscopy (fNIRS). METHODS: Sixty participants were recruited from the rehabilitation program in São Paulo, Brazil. Included patients were aged over 18 years, with traumatic unilateral lower-limb amputation, with PLP for at least 3 months after full recovery from amputation surgery. PLP and RLP levels were measured using visual analogue scales. fNIRS was performed during motor execution and motor mirror tasks for 20 s. In order to highlight possible variables related to variation in pain measures, univariate linear regression analyses were performed for both experimental conditions, resulting in four fNIRS variables (two hemispheres x two experimental conditions). Later, in order to test the topographic specificity of the models, eight multivariate regression analyses were performed (two pain scales x two experimental conditions x two hemispheres), including the primary motor cortex (PMC) related channel as an independent variable as well as five other channels related to the premotor area, supplementary area, and somatosensory cortex. All models were controlled for age, sex, ethnicity, and education. RESULTS: We found that: i) there is an asymmetric metabolic activation during motor execution and mirror task between hemispheres (with a predominance that is ipsilateral to the amputated limb), ii) increased metabolic response in the PMC ipsilateral to the amputation is associated with increased PLP (during both experimental tasks), while increased metabolic response in the contralateral PMC is associated with increased RLP (during the mirror motor task only); ii) increased metabolic activity of the ipsilateral premotor region is associated with increased PLP during the motor mirror task; iii) RLP was only associated with higher metabolic activity in the contralateral PMC and lower metabolic activity in the ipsilateral inferior frontal region during motor mirror task, but PLP was associated with higher metabolic activity during both tasks. CONCLUSION: These results suggest there is both task and region specificity for the association between the brain metabolic response and the two different types of post-amputation pain. The metabolic predominance that is ipsilateral to the amputated limb during both tasks was associated with higher levels of PLP, suggesting a cortical motor network activity imbalance due to potential interhemispheric compensatory mechanisms. The present work contributes to the understanding of the underlying topographical patterns in the motor-related circuits associated with pain after amputations.

Terapia do espelho em pacientes amputados por câncer com dor e sensação de membro fantasma ­ estudo piloto / [Mirror therapy in cancer amputee patients with pain and sensation of phantom limb - pilot study]

Introduction: Feeling and phantom pain are common sequelae after amputation of a limb from the body. Its etiology is not fully elucidated but is considered as a type of sensation and neuropathic pain perceived in the lost portion of the amputated limb caused by pathology in the central neurons with probable influences of peripheral and psychological mechanisms. The prevalence of phantom pain can be observed with variation of 26% and 80% of cancer patients who underwent this procedure. Alternative interventions called non-pharmacological therapies such as Mirror Therapy have increased attention for the treatment of sensation and phantom pain. The mirror image of normal body parts can help to reorganize and integrate the mismatch between proprioception and visual feedback of the amputated limb and may contribute to future appropriate interventions of this phenomenon. Objective: Investigate the effects of Mirror Therapy in cancer amputated patients with phantom limb pain and sensation. Materials and methods: A pilot study was designed as a randomized clinical trial with eight patients from 12 years of age, with reports of pain and phantom sensation after amputation of limb due to cancer, which were followed up in the adult and pediatric physiotherapy sectors, among May to November 2018, from 30 days of surgery, at a referral center for cancer treatment. The patients in the study were randomized into two groups, the Control Group (n=5), who underwent standard physiotherapy (exercises and braces of the stump) and the Mirror Therapy group (n=3) the Mirror Therapy. Results: Preliminary findings evaluating the initial effectiveness of Mirror Therapy in cancer patients are reported here. At the end of the study, three patients reported decreased drug use and the characteristics of phantom and phantom pain. Conclusion: Although the results were inconclusive, other studies with a larger population and robust methods of analysis encourage a broader investigation in the oncological population in order to improve and make appropriate adjustments in the evaluation and treatment of the therapy used.

Persona postamputada portadora de dolor de miembro fantasma: Dolor y cuerpo / Person carrying postamputed phantom limb pain: Pain and body

La presente investigación se plantea a través de un abordaje descriptivo-cualitativo. El objetivo fue describir y analizar “lo cotidiano” de la persona postamputada con dolor de miembro fantasma en el estado de Durango, México. El método utilizado fue exploratorio-descriptivo, y como técnica se empleó la entrevista semiestructurada. Los sujetos seleccionados provenían de seis municipios del estado de Durango, México. Debido a la naturaleza del estudio, participaron cuatro personas que al ser amputadas debutaron con dolor de miembro fantasma. El soporte teórico de la presente investigación está integrado y complementado por el pensamiento respecto a lo cotidiano de Maffesoli (1998),1 la corporalidad de David Le Breton (2002)2 y el dolor de David Le Breton (1999).3 Se construyeron tres categorías: 1. Lo corporal, 2. El tiempo y movimiento y 3. Trabajo y ocio.

This research is descriptive-qualitative approach, the aim was to describe and analyze the daily life of the person carrying postamputed phantom limb pain on state of Durango in Mexico. The method used was exploratory-descriptive, semistructured interview technique. The key informants selected as acting subjects, came from six municipalities of Durango’ State, Mexico. Due to the nature of this study, participated four people being amputated debut with Phantom Limb Pain. The theoretical support of this research is integrated and complemented by thinking about the daily life of Maffesoli (1998), the corporeality of David Le Breton (2002) and the pain of David Le Breton (1999). They built three categories: 1. The body, 2. Time and movement, 3. Work and Leisure.

Repercusión del miembro fantasma en la rehabilitación de pacientes amputados de miembros inferiores / Repercussion of the ghost extremity in the rehabilitation of lower limb amputees

Se realizó un estudio observacional descriptivo transversal sobre los fenómenos del miembro fantasma en pacientes amputados de miembros inferiores en el Hospital Docente Clínico-Quirúrgico Provincial Amalia Simoni de Camagüey, desde enero 2004 hasta diciembre 2008 para determinar la repercusión del mismo en su rehabilitación integral. El universo-muestra quedó constituido por 81 pacientes, mayores de 15 años, ambos sexos, por criterios de inclusión, exclusión y salida. Se utilizó encuesta de variables. Resultados: predominó el sexo masculino con 50 (61,7 por ciento) y la mayor frecuencia en el grupo de edad de 45 a 59 años: 28 (34,5 por ciento); prevaleció la sensación fantasma con 52 casos (64,2 por ciento); la causa traumática la más frecuente con 31 (38,3 por ciento); las mayores frecuencias estuvieron dadas por los horarios vespertinos y nocturnos con 32 (39,5 por ciento) y 25 (30,9 por ciento) respectivamente; se empleó la radiación infrarroja y los ejercicios en todos los pacientes; fue predominante la sensación fantasma con 41 casos, parte integrante de 63 pacientes (77,8 por ciento) del total que obtuvo su rehabilitación. Se logró evitar una desfavorable repercusión del fenómeno fantasma como complicación en los amputados de miembros inferiores al obtenerse una rehabilitación integral superior al 77 por ciento(AU)

A cross-sectional descriptive observational study was carried out on the phenomena of the ghost extremity of lower limb amputees in Amalia Simoni Clinical and Surgical Teaching Hospital, Camagüey, from January 2004 to December 2008 to determine its repercussion in the integral rehabilitation. The universe of study was made up of the patients older than 15 years, both sex, with confirmed main diagnosis and complication. Inclusion/exclusion and exit criteria were applied to 81 patients (sample). A survey, which considered the variables: age; sex; type of sensation, etiology and level of amputation; occurrence schedule and beginning of the phenomenon; physiotherapeutic techniques used; and integral rehabilitation, was carried out to collect data. Results: masculine sex was the most prominent with 50 (61.7 percent) and the greatest frequency was in the age group from 45 to 59 years: 28 (34.5 percent); the ghost sensation predominated with 52 cases (64.2 percent); the traumatic cause with 31 (38.3 percent)was the most frequent; the highest frequencies were in the afternoon and night schedules with 32 (39.5 percent) and 25 (30.9 percent) respectively; the infrared radiation and the exercises were applied to all the patients; the ghost sensation with 41 cases was predominant, integral part of 63 patients (77.8 percent) of the total who obtained their rehabilitation. It is concluded that the avoidance of the unfavorable repercussion of the ghost phenomenon, as a complication of the lower limb amputees, was achieved, obtaining a higher- to-77 percent integral rehabilitation(AU)

Repercusión del miembro fantasma en la rehabilitación de pacientes amputados de miembros inferiores / Repercussion of the ghost extremity in the rehabilitation of lower limb amputees

Se realizó un estudio observacional descriptivo transversal sobre los fenómenos del miembro fantasma en pacientes amputados de miembros inferiores en el Hospital Docente Clínico-Quirúrgico Provincial Amalia Simoni de Camagüey, desde enero 2004 hasta diciembre 2008 para determinar la repercusión del mismo en su rehabilitación integral. El universo-muestra quedó constituido por 81 pacientes, mayores de 15 años, ambos sexos, por criterios de inclusión, exclusión y salida. Se utilizó encuesta de variables. Resultados: predominó el sexo masculino con 50 (61,7 por ciento) y la mayor frecuencia en el grupo de edad de 45 a 59 años: 28 (34,5 por ciento); prevaleció la sensación fantasma con 52 casos (64,2 por ciento); la causa traumática la más frecuente con 31 (38,3 por ciento); las mayores frecuencias estuvieron dadas por los horarios vespertinos y nocturnos con 32 (39,5 por ciento) y 25 (30,9 por ciento) respectivamente; se empleó la radiación infrarroja y los ejercicios en todos los pacientes; fue predominante la sensación fantasma con 41 casos, parte integrante de 63 pacientes (77,8 por ciento) del total que obtuvo su rehabilitación. Se logró evitar una desfavorable repercusión del fenómeno fantasma como complicación en los amputados de miembros inferiores al obtenerse una rehabilitación integral superior al 77 por ciento.

A cross-sectional descriptive observational study was carried out on the phenomena of the ghost extremity of lower limb amputees in Amalia Simoni Clinical and Surgical Teaching Hospital, Camagüey, from January 2004 to December 2008 to determine its repercussion in the integral rehabilitation. The universe of study was made up of the patients older than 15 years, both sex, with confirmed main diagnosis and complication. Inclusion/exclusion and exit criteria were applied to 81 patients (sample). A survey, which considered the variables: age; sex; type of sensation, etiology and level of amputation; occurrence schedule and beginning of the phenomenon; physiotherapeutic techniques used; and integral rehabilitation, was carried out to collect data. Results: masculine sex was the most prominent with 50 (61.7 percent) and the greatest frequency was in the age group from 45 to 59 years: 28 (34.5 percent); the ghost sensation predominated with 52 cases (64.2 percent); the traumatic cause with 31 (38.3 percent)was the most frequent; the highest frequencies were in the afternoon and night schedules with 32 (39.5 percent) and 25 (30.9 percent) respectively; the infrared radiation and the exercises were applied to all the patients; the ghost sensation with 41 cases was predominant, integral part of 63 patients (77.8 percent) of the total who obtained their rehabilitation. It is concluded that the avoidance of the unfavorable repercussion of the ghost phenomenon, as a complication of the lower limb amputees, was achieved, obtaining a higher- to-77 percent integral rehabilitation.