title: Three-dimensional intercondylar notch volumes in a skeletally immature pediatric population: a magnetic resonance imaging-based anatomic comparison of knees with torn and intact anterior cruciate ligaments.
abstract: OBJECTIVE
  To determine whether 3-dimensional notch volume, measured with magnetic resonance imaging (MRI), differs significantly between knees with torn and intact anterior cruciate ligaments (ACLs) after sports injury in a skeletally immature pediatric population.
  
  
  METHODS
  MRI studies of 50 pediatric patients (age range, 10 to 17 years) with ACL tears were compared with 50 age- and sex-matched intact-ACL control patients. All patients had open physes and underwent MRI after a sports injury. Notch volume was calculated through manual segmentation of notch boundaries seen on axial 1.5-T proton density-weighted images. Two-dimensional (2D) measurements (notch width and notch width index) were made on coronal proton density-weighted MRI studies. Notch volume was compared between groups by use of the Mann-Whitney U test. Pearson correlation coefficients were also calculated between indices.
  
  
  RESULTS
  Notch volume was significantly lower in knees with ACL tears than in control knees (5.5 ± 1.1 cm(3)v 6.4 ± 1.5 cm(3), P = .002), whereas 2D notch width and notch width index did not differ significantly between these groups. Girls had significantly smaller notch volumes than boys (5.4 ± 1.2 cm(3)v 6.5 ± 1.3 cm(3), P < .001). Notch volume was not correlated with age but was moderately correlated with 2D notch width (r = 0.485, P < .001).
  
  
  CONCLUSIONS
  In adolescent patients with sports injuries, the 3-dimensional notch volume was significantly smaller in knees with ACL tears than in intact-ACL control knees. Notch volume was also significantly smaller in girls than in boys and did not vary significantly with age.
  
  
  METHODS
  Level III, case-control study.
authors.affiliation: Department of Radiology and Diagnostic Imaging, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Vimarsha Gopal
authors.initials: VG
authors.lastname: Swami
authors.forename: Myles
authors.initials: M
authors.lastname: Mabee
authors.forename: Catherine
authors.initials: C
authors.lastname: Hui
authors.forename: Jacob Lester
authors.initials: JL
authors.lastname: Jaremko
mesh_terms: D000293:Adolescent; D016118:Anterior Cruciate Ligament / Q000473:pathology*; D000070598:Anterior Cruciate Ligament Injuries; D001265:Athletic Injuries / Q000473:pathology*; D016022:Case-Control Studies; D002648:Child; D005260:Female; D005269:Femur / Q000254:growth & development / Q000473:pathology; D006801:Humans; D021621:Imaging, Three-Dimensional; D007718:Knee Injuries / Q000175:diagnosis*; D007719:Knee Joint / Q000254:growth & development / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009929:Organ Size; D015203:Reproducibility of Results