Spontaneous electromyographic potentials in cervical cord-injured patients are related to dysesthetic pain

A total of 61 traumatic cervical cord-injured patients were included in this study. Needle electromyography and nerve conduction study were performed at 6 to 24 weeks postinjury. Correlation between the presence of spontaneous electromyographic potentials and the presence of dysesthetic pain, as well as other clinical characteristics including age, gender, level of injury, severity of injury, spasticity, duration of injury, and performance of spinal surgery was statistically analyzed. Of the 31 patients who had spontaneous electromyographic potentials in their hands, 27 (87%) had dysesthetic pain in their limbs. Only 9 (30%) of the other 30 patients without spontaneous potentials developed dysesthetic pain. A significant correlation (P < 0.001) between the presence of spontaneous electromyographic potential and dysesthetic pain was found. The presence of spontaneous electromyographic potentials was also significantly (P < 0.05) correlated with severity of injury but not with age, gender, injury level, duration of injury, operation, and spasticity. In conclusion, the presence of spontaneous electromyographic potentials in cervical cord-injured patients was significantly related to the presence of dysesthetic pain. They occurred more often in patients with more severe injury.