title: The Efficacy of Intraoperative Neurophysiological Monitoring Using Transcranial Electrically Stimulated Muscle-evoked Potentials (TcE-MsEPs) for Predicting Postoperative Segmental Upper Extremity Motor Paresis After Cervical Laminoplasty.
abstract: METHODS
  Prospective study.
  
  
  OBJECTIVE
  To investigate the efficacy of transcranial electrically stimulated muscle-evoked potentials (TcE-MsEPs) for predicting postoperative segmental upper extremity palsy following cervical laminoplasty.
  
  
  BACKGROUND
  Postoperative segmental upper extremity palsy, especially in the deltoid and biceps (so-called C5 palsy), is the most common complication following cervical laminoplasty. Some papers have reported that postoperative C5 palsy cannot be predicted by TcE-MsEPs, although others have reported that it can be predicted.
  
  
  METHODS
  This study included 160 consecutive cases that underwent open-door laminoplasty, and TcE-MsEP monitoring was performed in the biceps brachii, triceps brachii, abductor digiti minimi, tibialis anterior, and abductor hallucis. A >50% decrease in the wave amplitude was defined as an alarm point. According to the monitoring alarm, interventions were performed, which include steroid administration, foraminotomies, etc.
  
  
  RESULTS
  Postoperative deltoid and biceps palsy occurred in 5 cases. Among the 155 cases without segmental upper extremity palsy, there were no monitoring alarms. Among the 5 deltoid and biceps palsy cases, 3 had significant wave amplitude decreases in the biceps during surgery, and palsy occurred when the patients awoke from anesthesia (acute type). In the other 2 cases in which the palsy occurred 2 days after the operation (delayed type), there were no significant wave decreases. In all of the cases, the palsy was completely resolved within 6 months.
  
  
  CONCLUSIONS
  The majority of C5 palsies have been reported to occur several days after surgery, but some of them have been reported to occur immediately after surgery. Our results demonstrated that TcE-MsEPs can predict the acute type, whereas the delayed type cannot be predicted.
  
  
  CONCLUSIONS
  A >50% wave amplitude decrease in the biceps is useful to predict acute-type segmental upper extremity palsy. Further examination about the interventions for monitoring alarm will be essential for preventing palsy.
authors.affiliation: Departments of *Orthopedic Surgery†Anesthesia and Intensive Care, Hiroshima City Asa Hospital‡Department of Orthopaedic Surgery, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima City, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Fujiwara
authors.forename: Hideki
authors.initials: H
authors.lastname: Manabe
authors.forename: Bunichiro
authors.initials: B
authors.lastname: Izumi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tanaka
authors.forename: Kazumi
authors.initials: K
authors.lastname: Kawai
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Tanaka
mesh_terms: D000368:Aged; D002574:Cervical Vertebrae / Q000601:surgery*; D057645:Deltoid Muscle / Q000503:physiopathology; D019054:Evoked Potentials, Motor; D005260:Female; D006801:Humans; D064795:Intraoperative Neurophysiological Monitoring; D065406:Laminoplasty / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D010291:Paresis / Q000175:diagnosis* / Q000209:etiology / Q000628:therapy; D011446:Prospective Studies; D013118:Spinal Cord Diseases / Q000150:complications; D065908:Transcranial Direct Current Stimulation; D016896:Treatment Outcome