title: Area of the tibial insertion site of the anterior cruciate ligament as a predictor for graft size.
abstract: OBJECTIVE
  To determine the distribution of different sizes of the area of the tibial insertion site among the population and to evaluate whether preoperative MRI measurements correlate with intraoperative findings to enable preoperative planning of the required graft size to cover the tibial insertion site sufficiently. The hypothesis was that the area of the tibial insertion site varies among individuals and that there is good agreement between MRI and intraoperative measurements.
  
  
  METHODS
  Intraoperative measurements of the tibial insertion site were taken on 117 patients. Three measurements were taken in each plane building a grid to cover the tibial insertion site as closely as possible. The mean of the three measurements in each plane was used for determination of the area. Two orthopaedic surgeons, who were blinded to the intraoperative measurements, took magnetic resonance imaging (MRI) measurements of the area of the tibial insertion site at two different time points.
  
  
  RESULTS
  The intraoperative measured mean area was 123.8 ± 21.5 mm2. The mean area was 132.8 ± 15.7 mm2(rater 1) and 136.7 ± 15.4 mm2(rater 2) when determined using MRI. The size of the area was approximately normally distributed. Inter-rater (0.89; 95 % CI 0.84, 0.92; p < 0.001) and intrarater reliability (rater 1: 0.97; 95 % CI 0.95, 0.98; p < 0.001; rater 2: 0.95; 95 % CI 0.92, 0.96; p < 0.001) demonstrated excellent test-retest reliability. There was good agreement between MRI and intraoperative measurement of tibial insertion site area (ICCs rater 1: 0.80; 95 % CI 0.71, 0.87; p < 0.001; rater 2: 0.87; 95 % CI 0.81, 0.91; p < 0.001).
  
  
  CONCLUSIONS
  The tibial insertion site varies in size and shape. Preoperative determination of the area using MRI is repeatable and enables planning of graft choice and size to optimally cover the tibial insertion site.
  
  
  METHODS
  III.
authors.affiliation: Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Kaufman Medical Building, Suite 1011, 3941 Fifth Avenue, Pittsburgh, PA, 15203, USA.|Trauma Department, Hannover Medical School (MHH), Hannover, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Guenther
authors.affiliation: Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Kaufman Medical Building, Suite 1011, 3941 Fifth Avenue, Pittsburgh, PA, 15203, USA.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Irarrázaval
authors.affiliation: Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Kaufman Medical Building, Suite 1011, 3941 Fifth Avenue, Pittsburgh, PA, 15203, USA.
authors.forename: Marcio
authors.initials: M
authors.lastname: Albers
authors.affiliation: Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Kaufman Medical Building, Suite 1011, 3941 Fifth Avenue, Pittsburgh, PA, 15203, USA.
authors.forename: Cara
authors.initials: C
authors.lastname: Vernacchia
authors.affiliation: Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Kaufman Medical Building, Suite 1011, 3941 Fifth Avenue, Pittsburgh, PA, 15203, USA.
authors.forename: James J
authors.initials: JJ
authors.lastname: Irrgang
authors.affiliation: Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Kaufman Medical Building, Suite 1011, 3941 Fifth Avenue, Pittsburgh, PA, 15203, USA.
authors.forename: Volker
authors.initials: V
authors.lastname: Musahl
authors.affiliation: Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Kaufman Medical Building, Suite 1011, 3941 Fifth Avenue, Pittsburgh, PA, 15203, USA. ffu@upmc.edu.
authors.forename: Freddie H
authors.initials: FH
authors.lastname: Fu
mesh_terms: D000293:Adolescent; D000328:Adult; D063405:Anatomic Variation; D016118:Anterior Cruciate Ligament / Q000033:anatomy & histology* / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries / Q000601:surgery; D059549:Anterior Cruciate Ligament Reconstruction; D005260:Female; D005269:Femur / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D013977:Tibia / Q000033:anatomy & histology* / Q000601:surgery*; D019737:Transplants; D055815:Young Adult
keywords: ACL; Anatomy; Anterior cruciate ligament; Graft size; Individualized; Tibial insertion site