RESUMO
La estimulación de la Médula Espinal (EME) es una técnica de neuromodulación que ha mostrado ser efectiva en el manejo de los trastornos motores propios de enfermedades tan devastadoras como la Enfermedad de Parkinson (EP) y las lesiones de la médula espinal. Considerando que ambas patologías cuentan con opciones terapéuticas limitadas, la EME se podría posicionar como una técnica prometedora. Los mecanismos por los cuales operaría la estimulación difieren en ambos casos, generando cambios en la circuitería espinal local en el caso de las lesiones medulares, y cambios supraespinales, en el caso de la EP. En esta revisión se busca analizar los efectos de la EME en ambas enfermedades, tanto en modelos animales como en pacientes, hacer una breve descripción de los mecanismos y aludir a los desafíos futuros propuestos para ambos casos. (AU)
Spinal cord stimulation (SCS) is a neurophysiological technique that has shown to be effective in modulating motor dysfunction associated with devastating diseases such as: Parkinson's disease (PD) and spinal cord injuries. Considering that both pathologies have limited treatment options, SCS could be considered as a potential useful technique. The mechanism by which stimulation operates differs in both cases, generating changes in local circuits in the case of spinal cord injuries and supraspinal changes in PD. This review aims to analyze the effects of EES on both diseases, focusing in the results observed in animal models and patients, give a brief description of the mechanisms behind and postulate the future challenges proposed for SCS in both pathologies.(AU)
Assuntos
Humanos , Masculino , Feminino , Estimulação da Medula Espinal , Doença de Parkinson , Doenças da Medula Espinal , Estimulação Elétrica Nervosa TranscutâneaRESUMO
The simultaneous and involuntary displacement of the opposite limb during a volitional movement is called mirror movements. They mimic the gesture, partly or wholly. They can be congenital, familiar or installed in various CNS pathologies. We present a 64 years old woman with familiar history of mirror movements that affect their hands, since childhood. At admission presented confused with left hemiplegia and homolateral sensory involvement. The brain CT defined a right ischemic stroke affecting the posterior limb of the internal capsule, lenticular nucleus, sub insular region and par ventricular white matter. The paretic left hand, unable to perform voluntary movements, presented mirror movements during volitional movements of the contra lateral hand. Neurophysiologic studies have suggested that mirror movements are due the activation of the direct corticospinal pathway or simultaneous discharge of both motor cortexes due inhibitory pathways failures. Cortical origin seems unlikely for the movements in this patient, due to the injury of the internal capsule. Our case could be interpreted by the simultaneously brain innervations on both anterior horns, together with a congenital deregulation of the Central Pattern Generator Networks.
Se denomina movimiento en espejo (ME) el desplazamiento involuntario, imitativo y simultáneo de la extremidad opuesta al de un movimiento volitivo. Los ME pueden tener un origen congénito y familiar o generarse por patologías diversas del sistema nervioso central. Se presenta una mujer de 64 años con el antecedente de ME desde la infancia de carácter familiar. Ingresa en estado confusional y presentando una hemiplejía y hemihipoestesia faciobraquicrural izquierda. La tomografía cerebral mostraba compromiso del brazo posterior de la cápsula interna, núcleo lenticular, región subinsular y de la sustancia blanca paraventricular. La mano izquierda pléjica que era incapaz de realizar movimientos voluntarios, se movía en espejo al mover la mano derecha. Esta curiosa manifestación hace necesario una más ajustada interpretación neurofisiológica de los movimientos en espejo. Se ha postulado una activación de la vía corticoespinal directa, o la descarga simultánea de ambas cortezas motoras por fallas en la natural inhibición transcortical. En este caso parece improbable un origen cortical contralateral de los movimientos, debido a la lesión de la cápsula. Tal vez podrían comprenderse los ME de esta paciente, si se demostrara una doble inervación de ambas astas anteriores, asociada a una falla en la inhibición normal por desregulación congénita de los Circuitos Generadores Centrales.
Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Hemiplegia/diagnóstico , Infarto Cerebral/complicações , Transtornos dos Movimentos/congênito , Transtornos dos Movimentos/fisiopatologia , Acidente Vascular Cerebral/complicações , Lateralidade Funcional , Mãos/fisiopatologia , Reflexo , Sincinesia , Sistema Nervoso Central/fisiopatologiaRESUMO
@#Spinal cord plasticity includes spontaneous neuronal plasticity and task-dependent plasticity which was respectively driven by spinal cord injury and special treatment.Spontaneous plasticity occurred at neuronal and synaptic sites,displaying various forms of axonal sprouting,unmasking of relatively ineffective functional connections and modification of synaptic efficacy.Task-dependent plasticity demonstrated reactivation of central generator pattern and functional reorganization of extensive spinal circuits.Exploration,induction and guidance of spinal cord plasticity will help determine the most optimal treatments and expand therapy methods to further promote function recovery of patients with spinal cord injury.
RESUMO
@# It is generally accepted that locomotion in mammals, including humans, is based on the activity of neuronal circuits within the spinal cord (the central pattern generator, CPG). Recent studies indicate a plastic behavior of the spinal neuronal circuits following a spinal cord injuries (SCI). Studies have shown that body weight support treadmill training (BWSTT) is effective in restoring locomotor function in cats with a complete spinal lesion. It has become possible to regain some locomotor activity in patients with spinal cord injury through an intense training on BWSTT, as in cat. So, it is a staired problem how to take advantage of the plasticity of spinal locomotor pattern generator and design the gait training program for SCI patients.