Prediction of recovery from upper extremity paralysis after stroke by measuring evoked potentials

Paralysis of the upper extremity is a severe motor impairment that can occur after stroke. Prediction of recovery from paralysis is difficult and is primarily based on subjective clinical evaluation. However, the integrity of the sensorimotor system can be assessed objectively and quantitatively by measuring evoked potentials. In this retrospective exploratory study, we evaluated the predictive value of motor and somatosensory evoked potentials for recovery from paralysis of the upper extremity. Motor and somatosensory evoked potentials were recorded in 29 patients who had had their first-ever infarction in the territory of the middle cerebral artery and who exhibited paralysis of the upper extremity. At follow-up, seven patients showed motor recovery. The evoked potential data were dichotomized into present or absent and related to the occurrence of motor recovery. Analysis revealed a significant association between the presence of evoked potentials early after stroke and the observed occurrence of motor recovery. These results suggest strongly that evoked potentials predict the occurrence of motor recovery of upper extremity paralysis in patients suffering from first-ever infarction in the territory of the middle cerebral artery.