title: Traction injury of the recurrent laryngeal nerve: Results of continuous intraoperative neuromonitoring in a swine model.
abstract: BACKGROUND
  Recurrent laryngeal nerve (RLN) palsy is the most serious complication after thyroidectomy. However, little is known about the degree of traction injury that causes loss of signal. The purpose of this study was to evaluate traction injuries in the swine RLN using continuous intraoperative neuromonitoring (IONM) and determine the traction power that results in loss of signal.
  
  
  METHODS
  Thirteen swine underwent traction injury to the RLNs with continuous IONM, and stress-strain curves were determined for 8 nerves using the universal material testing machine in an ex vivo model.
  
  
  RESULTS
  Traction injury at a mean power of 2.83 MPa caused loss of signal. The mean physiologic limit strain and tensile strength of the swine RLNs were found to be 15.0% and 4.9 MPa, respectively. Histological analysis showed no abnormal structural findings.
  
  
  CONCLUSIONS
  Traction injury of swine RLNs causes loss of signal at a power of 2.83 MPa. However, all injured nerves recovered within 7 days with no observed structural damage.
authors.affiliation: Department of Surgery, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Korea.
authors.forename: Hye Yoon
authors.initials: HY
authors.lastname: Lee
authors.affiliation: Advanced Materials Characterization Laboratory at School of Mechanical Engineering, Korea University, Seoul, Korea.
authors.forename: Young Geon
authors.initials: YG
authors.lastname: Cho
authors.affiliation: Department of Surgery, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Korea.
authors.forename: Ji Young
authors.initials: JY
authors.lastname: You
authors.affiliation: Advanced Materials Characterization Laboratory at School of Mechanical Engineering, Korea University, Seoul, Korea.
authors.forename: Byoung Ho
authors.initials: BH
authors.lastname: Choi
authors.affiliation: Department of Orthopaedic Surgery, Myongji Hospital, Seoul, Korea.
authors.forename: Joon Yub
authors.initials: JY
authors.lastname: Kim
authors.affiliation: Department of Otolaryngology - Head and Neck Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Taiwan.
authors.forename: Che-Wei
authors.initials: CW
authors.lastname: Wu
authors.affiliation: Department of Otolaryngology - Head and Neck Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Taiwan.
authors.forename: Feng-Yu
authors.initials: FY
authors.lastname: Chiang
authors.affiliation: Department of Surgery, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Korea.
authors.forename: Hoon Yub
authors.initials: HY
authors.lastname: Kim
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004576:Electromyography; D016343:Monitoring, Intraoperative / Q000379:methods*; D012009:Recurrent Laryngeal Nerve / Q000503:physiopathology*; D061226:Recurrent Laryngeal Nerve Injuries / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D013552:Swine; D013965:Thyroidectomy / Q000009:adverse effects; D014143:Traction
keywords: intraoperative neuromonitoring; recurrent laryngeal nerve; swine model; thyroidectomy; traction injury