title: Vastus medialis cross-sectional area is positively associated with patella cartilage and bone volumes in a pain-free community-based population.
abstract: BACKGROUND
  Although vastus medialis and lateralis are important determinants of patellofemoral joint function, their relationship with patellofemoral joint structure is unknown. The aim of this study was to examine potential determinants of vastus medialis and lateralis cross-sectional areas and the relationship between the cross-sectional area and patella cartilage and bone volumes.
  
  
  METHODS
  Two hundred ninety-seven healthy adult subjects had magnetic resonance imaging of their dominant knee. Vastus medialis and lateralis cross-sectional areas were measured 37.5 mm superior to the quadriceps tendon insertion at the proximal pole of the patella. Patella cartilage and bone volumes were measured from these images. Demographic data and participation in vigorous physical activity were assessed by questionnaire.
  
  
  RESULTS
  The determinants of increased vastus medialis and lateralis cross-sectional areas were older age (P <or= 0.002), male gender (P < 0.001), and greater body mass index (P <or= 0.07). Participation in vigorous physical activity was positively associated with vastus medialis cross-sectional area (regression coefficient [beta] 90.0; 95% confidence interval [CI] 38.2, 141.7) (P < 0.001) but not with vastus lateralis cross-sectional area (beta 10.1; 95% CI -18.1, 38.3) (P = 0.48). The cross-sectional area of vastus medialis only was positively associated with patella cartilage volume (beta 0.6; 95% CI 0.23, 0.94) (P = 0.001) and bone volume (beta 3.0; 95% CI 1.40, 4.68) (P < 0.001) after adjustment for potential confounders.
  
  
  CONCLUSIONS
  Our results in a pain-free community-based population suggest that increased cross-sectional area of vastus medialis, which is associated with vigorous physical activity, and increased patella cartilage and bone volumes may benefit patellofemoral joint health and reduce the long-term risk of patellofemoral pathology.
authors.affiliation: Department of Epidemiology and Preventive Medicine, Monash University Central and Eastern Clinical School, Melbourne, Australia. Patricia.Berry@med.monash.edu.au
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Berry
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Teichtahl
authors.forename: Ana
authors.initials: A
authors.lastname: Galevska-Dimitrovska
authors.forename: Fahad S
authors.initials: FS
authors.lastname: Hanna
authors.forename: Anita E
authors.initials: AE
authors.lastname: Wluka
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Wang
authors.forename: Donna M
authors.initials: DM
authors.lastname: Urquhart
authors.forename: Dallas R
authors.initials: DR
authors.lastname: English
authors.forename: Graham G
authors.initials: GG
authors.lastname: Giles
authors.forename: Flavia M
authors.initials: FM
authors.lastname: Cicuttini
mesh_terms: D000328:Adult; D000368:Aged; D002358:Cartilage, Articular / Q000033:anatomy & histology / Q000254:growth & development*; D015331:Cohort Studies; D003153:Community Health Services; D015444:Exercise / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology; D009929:Organ Size; D010146:Pain / Q000453:epidemiology / Q000473:pathology / Q000517:prevention & control*; D010147:Pain Measurement / Q000379:methods; D010329:Patella / Q000033:anatomy & histology / Q000254:growth & development*; D052097:Quadriceps Muscle / Q000033:anatomy & histology / Q000254:growth & development*