title: Patient-specific assessment of dysmorphism of the femoral head-neck junction: a statistical shape model approach.
abstract: BACKGROUND
  Objective quantification of anatomical variations about the femur head-neck junction in pre-operative planning for surgical intervention in femoro-acetabular impingement is problematic, as no clear definition of average normal anatomy for a specific subject exists.
  
  
  METHODS
  We have defined the normal-equivalent of a subject's anatomy by using a statistical shape model and geometric shape optimization for finding correspondences, while excluding the femoral head-neck junction during the fitting procedure. The presented technique was evaluated on a cohort of 20 patients.
  
  
  RESULTS
  Difference in α-angle measurement between the actual morphology and the predicted normal-equivalent, averaged 1.3° (SD 1.7°) in the control group versus 8° (SD 7.3°) in the patient group (p < 0.05).
  
  
  CONCLUSIONS
  Defining normal equivalent anatomy is effective in quantifying anatomical dysmorphism of the femoral head-neck junction and as such can improve presurgical analysis of patients diagnosed with femoro-acetabular impingement. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, Belgium.|Department of Trauma and Orthopaedics, Addenbrooke's-Cambridge University Hospitals, UK.
authors.forename: Vikas
authors.initials: V
authors.lastname: Khanduja
authors.affiliation: Department of Radiology, Jan Palfijn Hospital, Ghent, Belgium.
authors.forename: Nick
authors.initials: N
authors.lastname: Baelde
authors.affiliation: Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, Belgium.
authors.forename: Andreas
authors.initials: A
authors.lastname: Dobbelaere
authors.affiliation: Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, Belgium.
authors.forename: Jan
authors.initials: J
authors.lastname: Van Houcke
authors.affiliation: Department of Computer Science, University of Southern California, Los Angeles, USA.
authors.forename: Hao
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, Belgium.
authors.forename: Christophe
authors.initials: C
authors.lastname: Pattyn
authors.affiliation: Department of Orthopaedic Surgery and Traumatology, Ghent University Hospital, Belgium.
authors.forename: Emmanuel A
authors.initials: EA
authors.lastname: Audenaert
mesh_terms: D000077:Acetabulum / Q000601:surgery; D000293:Adolescent; D000328:Adult; D000465:Algorithms; D015331:Cohort Studies; D057925:Femoracetabular Impingement / Q000601:surgery*; D005269:Femur / Q000601:surgery; D005270:Femur Head / Q000601:surgery*; D005272:Femur Neck / Q000601:surgery*; D006621:Hip Joint / Q000601:surgery; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D015233:Models, Statistical; D025321:Surgery, Computer-Assisted; D055815:Young Adult
keywords: computed tomography; femoro-acetabular impingement; hip; image analysis; surgical planning