Abstract
Introduction
IOM is a standard care in cases of scoliosis.. there is more controversial their use in mubar pathology.. there are 5% lessions of nerve roots. There is a debate about the stimilation thresholds, to evaluate possibilities of medial positioning pedicular screws. The objetive of this paper is Evaluation of the effect of chronic compression of the lumbar roots in relation to thresholds direct stimulation.
Material and Methods:Study Design:• prospective case series with measurement and threshold register direct stimulation of lumbar roots.• 80 patients (43 women and 199 nerve roots) consecutive undergoing spinal surgery in a period of six months (January to October 2014), 7 surgeons and one neurophysiologist.• Average age: 52.87 (SD = 14.9)• 199 were stimulated nerve roots formDirect recording their stimulation threshold.
Results
Stimulating a nerve roots 199 average 2.82 per patient (SD = 1• 52 (26.1%) were considered preoperatively chronically compressed. No differences were found in thresholds stimulation of different lumbar levels (e.g., L2, L3, L4, L5 and S1) or chronically compressed roots or non-compressed (ANOVA, p > 0.05; p = 0.190). Average maximum stimulation intensity 6.34 mA (SD = 7.2). Nerve roots uncompressed presented a average intensity threshold stimulation 4.33 mA (SD = 3.6) chronically compressed nerve roots. They had an average intensity thresholdstimulation of 11.93 mA (SD = 10.9). This difference was statistically significant (TStudent, p < 0.0001). No association was found between age and theaverage intensity of stimulus or between roots chronically compressed or non-compressed.
Conclusion
If you are using direct stimulation path of the pedicle and / or to confirm the screw indemnity pedicle, we bear in mind theexistence of symptoms of nerve root compression previously. As shown in this study, these variables determine a threshold stimulation intensity greater root to confirm the proper positioning screw. We could generate false negative results, and thus to detect a possible improper positioning intrapedicular screw.