title: Femoral sulcus angle and increased patella facet cartilage volume in an osteoarthritic population.
abstract: OBJECTIVE
  The patellofemoral joint is an example of an incongruent articulation commonly affected by osteoarthritis (OA). The relationship between femoral sulcus angle and the development and progression of patellofemoral OA is unclear. The aim of this study was to examine the relationship between the femoral sulcus angle at baseline and patella cartilage volume at baseline and at 2-year follow-up among community based adults with established knee OA.
  
  
  METHODS
  One hundred subjects had magnetic resonance imaging of their symptomatic knee at baseline and at 2-year follow-up. From these images, patella cartilage volume was determined. Radiographic skyline views of the patellofemoral joint were taken at baseline to measure the femoral sulcus angle.
  
  
  RESULTS
  For every 1 degrees increase in the femoral sulcus angle (i.e., as the sulcus angle became more shallow) there was an associated 9.1mm3 (95% CI 3.1, 15.0) increase in medial patella cartilage volume at baseline (P=0.003). There was a similar trend that approached statistical significance between the femoral sulcus angle and the lateral patella facet cartilage volume at baseline (P=0.09). There was no association between the femoral sulcus angle at baseline and the change in patella cartilage volume over 2 years in either patellofemoral compartment.
  
  
  CONCLUSIONS
  These results infer that the femoral sulcus angle is a cross-sectional determinant of the amount of patella cartilage, but is not a major determinant of the annual change of patella cartilage volume among people with knee OA. These data suggest that a shallower sulcus in the context of established OA may be an advantageous anatomical variant. Further longitudinal studies are required to determine the role of the femoral sulcus angle in OA.
authors.affiliation: Department of Epidemiology and Preventive Medicine, Monash University, Central and Eastern Clinical School, Alfred Hospital, Melbourne, Vic 3004, Australia.
authors.forename: M
authors.initials: M
authors.lastname: Davies-Tuck
authors.forename: A J
authors.initials: AJ
authors.lastname: Teichtahl
authors.forename: A E
authors.initials: AE
authors.lastname: Wluka
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.forename: D M
authors.initials: DM
authors.lastname: Urquhart
authors.forename: J
authors.initials: J
authors.lastname: Cui
authors.forename: F M
authors.initials: FM
authors.lastname: Cicuttini
mesh_terms: D000368:Aged; D002358:Cartilage, Articular / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000473:pathology*; D010329:Patella / Q000000981:diagnostic imaging; D011859:Radiography