Original Article

Does Intraoperative Electromyographic Monitoring in Lumbar Microdiscectomy Correlate with Postoperative Pain?

Authors: Vassilios G. Dimopoulos, MD, Carlos H. Feltes, MD, Kostas N. Fountas, MD, Ioannis Z. Kapsalakis, MD, Robert L. Vogel, PHD, Bridget Fuhrmann, RN, CNIM, Arthur A. Grigorian, MD, Kim W. Johnston, MD, Hugh F. Smisson, III, MD, Joe S. Robinson, MD


Objectives: Our objective was to correlate the findings of intraoperative electromyographic (EMG) monitoring with immediate postoperative pain in patients undergoing lumbar microdiscectomy.

Methods: A total of 112 patients undergoing de novo lumbar microdiscectomy were prospectively randomized into a control group (n = 45) and a study group (n = 67) in which intraoperative EMG monitoring was used. Postoperative pain and postoperative narcotic consumption were recorded for each patient.

Results: The presence or absence of EMG monitoring did not influence the level of reported pain in any anatomic area. In the monitored group, the degree of recorded nerve root irritation did not correlate with reported pain or postoperative narcotic consumption. The level of back pain was found to be significantly higher than the level of hip and calf pain (P < 0.0001).

Conclusions: In our study no correlation was found between intraoperative EMG findings and immediate postoperative pain.

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