title: Comparison Between Sexes of Bone Contusions and Meniscal Tear Patterns in Noncontact Anterior Cruciate Ligament Injuries.
abstract: BACKGROUND
  Valgus load has been linked to female predominance and mechanism for noncontact anterior cruciate ligament (ACL) injuries. Magnetic resonance imaging (MRI) studies reporting frequent medial contusions in noncontact ACL injuries suggest anterior translation rather than a valgus mechanism.
  
  
  OBJECTIVE
  Bone contusion and meniscal tear patterns differ between sexes.
  
  
  METHODS
  Case series; Level of evidence, 4.
  
  
  METHODS
  This study included a review of clinic notes, operative reports, and MRI of patients younger than 20 years who underwent acute primary ACL reconstruction for a noncontact injury between January 1, 2005, and January 1, 2010. A blinded musculoskeletal MRI radiologist reported the incidence of medial and lateral femoral and tibial bone contusions on MRI, as well as the severity of medial versus lateral tibial contusions. The location of the bone contusions and meniscal tears and the maximal tibial contusion severity were compared through chi-square analysis (statistical significance, P < .05).
  
  
  RESULTS
  A total of 73 patients met inclusion criteria: 28 males, 45 females; mean age, 16.1 ± 1.7 years (males), 16.5 ± 1.7 years (females). No significant differences were noted between sexes for location of tibial contusions (P = .32), femoral contusions (P = .44), or meniscal tears (P = .715). The most common tibial contusion pattern was to have both medial and lateral tibial contusions, in both male (57%) and female (60%) patients. The most common femoral contusion pattern was lateral only in females (62%) and both medial and lateral in males (50%). The percentage of female (29%) and male (29%) patients with isolated medial meniscal tears was nearly identical. More males (29%) than females (18%) had isolated lateral meniscal tears (P = .72). No significant difference in the relative severity of the tibial contusions was noted (P = .246). The lateral tibial contusion was rated as being more severe than the medial in the majority of females (64%) and males (57%).
  
  
  CONCLUSIONS
  No significant differences were detected between sexes with noncontact ACL injuries for location of tibial or femoral contusions or meniscal tears or for severity of medial versus lateral tibial contusions. The MRI data were not consistent with the valgus collapse mechanism of injury.
authors.affiliation: Division of Orthopaedic Surgery, Bassett Healthcare Network, Cooperstown, New York, USA Jocelyn.Wittstein@bassett.org.
authors.forename: Jocelyn
authors.initials: J
authors.lastname: Wittstein
authors.affiliation: Department of Radiology, Musculoskeletal MRI Division, Duke University Medical Center, Durham, North Carolina, USA.
authors.forename: Emily
authors.initials: E
authors.lastname: Vinson
authors.affiliation: Department of Orthopaedic Surgery, Duke University Medical Center, Durham, North Carolina, USA.
authors.forename: William
authors.initials: W
authors.lastname: Garrett
mesh_terms: D000293:Adolescent; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods; D002358:Cartilage, Articular / Q000601:surgery*; D003288:Contusions / Q000473:pathology*; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D013977:Tibia / Q000601:surgery; D000070600:Tibial Meniscus Injuries
keywords: anterior cruciate ligament; contusions; magnetic resonance imaging; sex