Incidence of peripheral nerve injury during shoulder arthroplasty when motor evoked potentials are monitored

• Published in: Journal of clinical monitoring and computing 2018-10, Vol.32 (5), p.897-906
• Main Authors: Aleem, Alexander W., Wilent, W. Bryan, Narzikul, Alexa C., Kuntz, Andrew F., Chang, Edward S., Williams, Gerald R., Abboud, Joseph A.
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Anesthesiology; Arthroplasty, Replacement, Shoulder - adverse effects; Biomedical materials; Criteria; Critical Care Medicine; Decision making; Diagnostic systems; Evoked potentials; Evoked Potentials, Motor - physiology; Female; Health Sciences; Humans; Incidence; Injuries; Intensive; Intraoperative Complications - diagnosis; Intraoperative Complications - epidemiology; Intraoperative Complications - etiology; Intraoperative Neurophysiological Monitoring - methods; Joint surgery; Male; Medicine; Medicine & Public Health; Middle Aged; Original Research; Peripheral Nerve Injuries - diagnosis; Peripheral Nerve Injuries - epidemiology; Peripheral Nerve Injuries - etiology; Reduction; Retrospective Studies; Statistics for Life Sciences; Surgical implants
• ISSN: 1387-1307; 1573-2614
• DOI: 10.1007/s10877-017-0080-5

To report the incidence of clinically detectable nerve injuries when utilizing transcranial electrical motor evoked potentials (MEPs) during shoulder arthroplasty. A retrospective review of patients undergoing shoulder arthroplasty with continuous IONM was performed. The criteria for nerve alerts was an 80% amplitude reduction in MEPs. The primary outcome measure was post-operative clinically detectable nerve deficit. An additional retrospective analysis on a subset of cases using an all-or-none (100% amplitude reduction) criterion applied to the deltoid was performed. Two hundred eighty four arthroplasty cases were included. There were no permanent post-operative nerve injuries and two transient nerve injuries (0.7%). MEP alerts occurred in 102 cases (36.2%). Nineteen (6.7%) cases did not have signals return above alert threshold at closure. These cases were significantly associated with post-operative nerve injury (p = 0.03). There were no false negatives, making sensitivity 100% and specificity was 93.9%. In the subset of cases in which an all-or-none criterion was retrospectively applied to just the deltoid, MEP alerts occurred in just 17.9% of cases; specificity improved to 98.0%. We conclude that utilization of the real-time diagnostic MEP data during shoulder arthroplasty aids surgeons in decision making regarding impending peripheral nerve injuries.