title: Correlation of interosseous membrane tears to the level of the fibular fracture.
abstract: OBJECTIVE
  To correlate interosseous membrane (IOM) tears of the ankle to the height of fibular fractures in operative ankle fractures.
  
  
  METHODS
  Prospective clinical trial.
  
  
  METHODS
  University Level 1 trauma center.
  
  
  METHODS
  All patients admitted with a closed operative ankle fracture were included. Of 93 patients originally evaluated, 73 patients had adequate MRI for evaluation.
  
  
  METHODS
  Open reduction and internal fixation of each ankle fracture was performed after preoperative MRI evaluation of the IOM. Transsyndesmotic screw fixation was performed when evidence of syndesmotic instability was shown by intraoperative stress testing.
  
  
  METHODS
  Radiographs were analyzed for fracture classification and prediction of ligamentous injuries about the ankle. MRI evaluated the IOM integrity, correlating it to the height of the fibular fracture.
  
  
  RESULTS
  Of the 73 ankle fractures with adequate MRI evaluation, 30 had identifiable complete IOM tears on MRI. Ten of the 30 IOM tears did not correlate with the level of the fractured fibula. Seven cases had IOM tears proximal to the fibular fracture as detected by MRI. Five of these cases were Weber B type fractures, and two were Weber C type fracture patterns. Conversely, three cases of Weber C type fractures had IOM tears that remained distal to the level of the fibular fracture.
  
  
  CONCLUSIONS
  The level of the fibular fracture does not correlate reliably with the integrity or extent of the interosseous membrane tears identified on MRI in operative ankle fractures. One cannot consistently estimate the integrity of the IOM and subsequent need for transsyndesmotic fixation based solely on the level of the fibular fracture. An intraoperative syndesmotic stress test is recommended to establish the presence or absence of syndesmotic instability.
authors.affiliation: Department of Orthopaedic Surgery, Albert Einstein College of Medicine, Hospital for Special Surgery, New York, NY 10021, USA.
authors.forename: Jason H
authors.initials: JH
authors.lastname: Nielson
authors.forename: Julian G
authors.initials: JG
authors.lastname: Sallis
authors.forename: Hollis G
authors.initials: HG
authors.lastname: Potter
authors.forename: David L
authors.initials: DL
authors.lastname: Helfet
authors.forename: Dean G
authors.initials: DG
authors.lastname: Lorich
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016512:Ankle Injuries / Q000000981:diagnostic imaging / Q000601:surgery*; D001863:Bone Screws; D005260:Female; D005360:Fibula / Q000000981:diagnostic imaging / Q000293:injuries*; D005593:Fracture Fixation, Internal; D006801:Humans; D008023:Ligaments, Articular / Q000293:injuries*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011859:Radiography