title: Skeletal imaging following reconstruction of the posterior cruciate ligament: in vivo comparison of fluoroscopy, radiography, and computed tomography.
abstract: OBJECTIVE
  Intra- and postoperative validation of anatomic footprint replication in posterior cruciate ligament (PCL) reconstruction can be conducted using fluoroscopy, radiography, or computed tomography (CT) scans. However, effectiveness and exposure to radiation of these imaging modalities are unknown. The objective of this study was to evaluate the comparative effectiveness of fluoroscopy, radiography, and CT in detecting femoral and tibial tunnel positions following an all-inside reconstruction of the PCL ligament in vivo. The study design was a retrospective case series.
  
  
  METHODS
  Intraoperative fluoroscopic images, postoperative radiographs, and CT scans were obtained in 50 consecutive patients following single-bundle PCL reconstruction. The centers of the tibial and femoral tunnel apertures were identified and correlated to measurement grid systems. The results of fluoroscopic, radiographic, and CT measurements were compared to each other and accumulated radiation dosages were calculated.
  
  
  RESULTS
  Comparing the imaging groups, no statistically significant difference could be detected for the reference of the femoral tunnel to the intercondylar depth and height, for the reference of the tibial tunnel to the mediolateral diameter of the tibial plateau and for the superoinferior distance of the tibial tunnel entry to the tibial plateau and to the former physis line. Effective doses resulting from fluoroscopic, radiographic, and CT exposure averaged 2.9 mSv, standard deviation (±SD) 4.1 mSv, to 1.3 ± 0.8 mSv and to 3.6 ± 1.0 mSv, respectively.
  
  
  CONCLUSIONS
  Fluoroscopy, radiography, and CT yield approximately equal effectiveness in detecting parameters used for quality validation intra- and postoperatively. An accumulating exposure to radiation must be considered.
authors.affiliation: Department for Trauma Surgery and Sports Traumatology, Academic Hospital Feldkirch, Carinagasse 47, 6800, Feldkirch, Austria, michael.osti@lkhf.at.
authors.forename: Michael
authors.initials: M
authors.lastname: Osti
authors.forename: Alessa
authors.initials: A
authors.lastname: Krawinkel
authors.forename: Karl Peter
authors.initials: KP
authors.lastname: Benedetto
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D005471:Fluoroscopy / Q000379:methods; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007432:Intraoperative Period; D007719:Knee Joint / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D016119:Posterior Cruciate Ligament / Q000000981:diagnostic imaging* / Q000601:surgery*; D011184:Postoperative Period; D019651:Plastic Surgery Procedures; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult