Roles of preoperative and early postoperative electrodiagnosis in brachial plexus injury patients undergoing nerve transfer operations: retrospective feasibility study

Abstract

Objective The purpose of this retrospective observational study was to assess the feasibility of electrodiagnostic parameters, perioperatively, and to discover optimal values as prognostic factors for patients with brachial plexus injury undergoing nerve transfer operations. Methods We retrospectively reviewed the records of 11 patients who underwent nerve transfer surgery. The patients underwent perioperative electrodiagnosis (EDX) before and approximately 6 months after surgery. We evaluated the compound muscle action potential (CMAP) ratio, motor unit recruitment, and their interval changes. To evaluate motor strength, we used the Medical Research Council (MRC) grade, 6 and 12 months after surgery. We evaluated the relationships between improved CMAP ratio, and motor unit recruitment and MRC grade changes 6 and 12 months postoperatively. Results All parameters increased significantly after surgery. The CMAP ratio improvement 6 months after surgery correlated with the MRC grade change from baseline to 12 months, with a correlation coefficient of 0.813. Conclusion EDX parameters improved significantly postoperatively, and the CMAP ratio improvement 6 months after surgery correlated with the clinical outcomes at 1 year. The results of perioperative EDX might help establish long-term treatment plans for patients who undergo nerve transfer surgery.

Letter to the Editor: Video-assisted thoracoscopic surgery aided full-length phrenic nerve transfer for restoration of elbow flexion

“…and underwent nerve transfer operations. 4 Providing this information would bolster this study's data integrity and the authors' conclusions regarding the physiological benefits achieved by the techniques employed.…”

“…A study by Son et al found that the compound muscle action potential (CMAP) improved and correlated with the MRC grade as the patients recovered from a brachial plexus injury and underwent nerve transfer operations. 4 Providing this information would bolster this study’s data integrity and the authors’ conclusions regarding the physiological benefits achieved by the techniques employed.…”