Acta Ortopédica Mexicana

Escobar-Cedillo RE, Castillo-Herrera M, Lona-Pimentel S, Rosales LM
Standardization of method and record conditions of somatosensorial evoked potentials in corrective surgery for deformities of the spine. Neurophysiological study in 82 operated cases
Acta Ortop Mex 2000; 14 (1)

Language: Español
References: 33
Page: 84-87
PDF: 74.24 Kb.

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There are reports of neurologic alterations after surgical interventions in the correction of spine deformities, due to the risk that they involve. It has been used an “wake up” test to evaluate the neurologic integrity, but this has not been enough. Therefore, there has been established neurophysiologic techniques such the somatosensorial evoked potentials (SEP) to value this integrity. This method, without being invasive, evaluates the somatosensorial track avoiding the risk of spinal cord injury; however, there has been observed too, in some occasions, “false positive” and “true positive” with it. In our hospital we studied 82 patients with an average of age of 15.4, to whom there were done SEP with recording from the neck and scalp and stimulation applied in tibial nerve to each leg. We didn’t find any significative difference in the records before and after the surgery with p › 0.05. In 9 patients the there were “false positive” and in 7 patients SEP were abnormal, showing postoperative neurological changes from dysesthesias to spinal cord injury. Due to the risk of neurological injury in such interventions one must monitoring not only with SEP the sensory track, but also the motor track with some other method to diminish the incidence of “false positive” and negatives, to give more reliable information to the surgeon for the benefit of the patient.

Key words: evoked potentials, somatosensory, stability, spine, surgery.


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