title: Relationship Between the Risk of Suffering a First-Time Noncontact ACL Injury and Geometry of the Femoral Notch and ACL: A Prospective Cohort Study With a Nested Case-Control Analysis.
abstract: BACKGROUND
  The morphometric characteristics of the anterior cruciate ligament (ACL) and the femoral intercondylar notch within which it resides have been implicated as risk factors for injuries to this important stabilizer of the knee. Prior research has produced equivocal results with differing methodologies, and consequently, it is unclear how these characteristics affect the injury risk in male and female patients.
  
  
  OBJECTIVE
  The morphometric characteristics of the ACL and femoral intercondylar notch are individually and independently associated with the risk of suffering a noncontact ACL injury, and these relationships are different in male and female patients.
  
  
  METHODS
  Case-control study; Level of evidence, 3.
  
  
  METHODS
  Magnetic resonance imaging scans of the bilateral knees were obtained on 88 case-control pairs (27 male, 61 female) matched for age, sex, and participation on the same sports team. Patients had suffered a grade III, first-time, noncontact ACL tear. The femoral notch width at 4 locations, the thickness of the bony ridge at the anteromedial outlet of the femoral notch, the femoral notch volume, ACL volume, and ACL cross-sectional area were measured.
  
  
  RESULTS
  Multivariate analysis of combined data from male and female patients revealed that decreased ACL volume (odds ratio [OR], 0.829), decreased femoral notch width (OR, 0.700), and increased bony ridge thickness at the anteromedial outlet of the femoral notch (OR, 1.614) were significant independent predictors of an ACL injury. Separate analyses of male and female patients indicated that the femoral notch ridge may be more strongly associated with a risk in female patients, while ACL volume is more strongly associated with a risk in male patients. However, statistical analysis performed with an adjustment for body weight strengthened the association between ACL volume and the risk of injuries in female patients.
  
  
  CONCLUSIONS
  Morphometric features of both the ACL and femoral notch combine to influence the risk of suffering a noncontact ACL injury. When included together in a multivariate model that adjusts for body weight, the effects of the morphometric measurements are similar in male and female patients. If body weight is not taken into consideration, ACL volume is not associated with a risk in female patients.
authors.affiliation: McClure Musculoskeletal Research Center, Department of Orthopaedics and Rehabilitation, University of Vermont College of Medicine, Burlington, Vermont, USA.
authors.forename: Darryl C
authors.initials: DC
authors.lastname: Whitney
authors.affiliation: McClure Musculoskeletal Research Center, Department of Orthopaedics and Rehabilitation, University of Vermont College of Medicine, Burlington, Vermont, USA.
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Sturnick
authors.affiliation: Department of Medical Biostatistics, University of Vermont, Burlington, Vermont, USA.
authors.forename: Pamela M
authors.initials: PM
authors.lastname: Vacek
authors.affiliation: Department of Medical Biostatistics, University of Vermont, Burlington, Vermont, USA.
authors.forename: Mike J
authors.initials: MJ
authors.lastname: DeSarno
authors.affiliation: McClure Musculoskeletal Research Center, Department of Orthopaedics and Rehabilitation, University of Vermont College of Medicine, Burlington, Vermont, USA.
authors.forename: Mack
authors.initials: M
authors.lastname: Gardner-Morse
authors.affiliation: McClure Musculoskeletal Research Center, Department of Orthopaedics and Rehabilitation, University of Vermont College of Medicine, Burlington, Vermont, USA.
authors.forename: Timothy W
authors.initials: TW
authors.lastname: Tourville
authors.affiliation: McClure Musculoskeletal Research Center, Department of Orthopaedics and Rehabilitation, University of Vermont College of Medicine, Burlington, Vermont, USA.
authors.forename: Helen C
authors.initials: HC
authors.lastname: Smith
authors.affiliation: McClure Musculoskeletal Research Center, Department of Orthopaedics and Rehabilitation, University of Vermont College of Medicine, Burlington, Vermont, USA.
authors.forename: James R
authors.initials: JR
authors.lastname: Slauterbeck
authors.affiliation: McClure Musculoskeletal Research Center, Department of Orthopaedics and Rehabilitation, University of Vermont College of Medicine, Burlington, Vermont, USA.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Johnson
authors.affiliation: Department of Kinesiology, University of North Carolina at Greensboro, Greensboro, North Carolina, USA.
authors.forename: Sandra J
authors.initials: SJ
authors.lastname: Shultz
authors.affiliation: Department of Ocean and Mechanical Engineering, Florida Atlantic University, Boca Raton, Florida, USA.
authors.forename: Javad
authors.initials: J
authors.lastname: Hashemi
authors.affiliation: McClure Musculoskeletal Research Center, Department of Orthopaedics and Rehabilitation, University of Vermont College of Medicine, Burlington, Vermont, USA bruce.beynnon@uvm.edu.
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Beynnon
mesh_terms: D000070598:Anterior Cruciate Ligament Injuries; D001835:Body Weight; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D005269:Femur / Q000473:pathology*; D006801:Humans; D007718:Knee Injuries / Q000473:pathology*; D007719:Knee Joint / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D015999:Multivariate Analysis; D011446:Prospective Studies; D012307:Risk Factors
keywords: ACL; femoral intercondylar notch; knee anatomy