title: Patellar tendon ultrasonography in asymptomatic active athletes reveals hypoechoic regions: a study of 320 tendons. Victorian Institute of Sport Tendon Study Group.
abstract: OBJECTIVE
  To compare patellar tendon sonographic findings in active, currently asymptomatic, elite athletes with those in nonathletic controls.
  
  
  METHODS
  Cross-sectional cohort study with convenience control sample.
  
  
  METHODS
  The Victorian Institute of Sport Tendon Study Group, an institutional elite athlete study group in Australia.
  
  
  METHODS
  Two hundred elite male and female athletes from the sports of basketball, cricket, netball, and Australian rules football. Forty athletes who had current symptoms of jumper's knee were excluded from analysis, leaving 320 subject tendons in athletes who were currently asymptomatic. Twenty-seven nonathletic individuals served as controls.
  
  
  METHODS
  Sonographic patellar tendon appearance. We measured the dimensions of subject tendons and noted the presence or absence of hypoechoic regions and tendon calcification. Dimensions of hypoechoic regions were measured, and approximate cross-sectional areas were calculated. Chi-squared analysis was used to test the prevalence of hypoechoic regions in subjects and controls and men and women.
  
  
  RESULTS
  In currently asymptomatic subjects, hypoechoic regions were more prevalent in athlete tendons (22%) than in controls (4%), in male subject tendons (30%) than in female subjects (14%), and in basketball players (32%) than in other athletes (9%) (all p < 0.01). Bilateral tendon abnormalities were equally prevalent in men and women but more prevalent in basketball players (15%) than in other athletes (3%) (p < 0.05). Sonographic hypoechoic regions were present in 35 of 250 (14%) patellar tendons in athletes who had never had anterior knee pain.
  
  
  CONCLUSIONS
  Patellar tendon sonographic hypoechoic areas were present in asymptomatic patellar tendons of a proportion of elite athletes but rarely present in controls. This has implications for clinicians managing athletes with anterior knee pain.
authors.affiliation: Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Parkville, Australia.
authors.forename: J L
authors.initials: JL
authors.lastname: Cook
authors.forename: K M
authors.initials: KM
authors.lastname: Khan
authors.forename: P R
authors.initials: PR
authors.lastname: Harcourt
authors.forename: Z S
authors.initials: ZS
authors.lastname: Kiss
authors.forename: M W
authors.initials: MW
authors.lastname: Fehrmann
authors.forename: L
authors.initials: L
authors.lastname: Griffiths
authors.forename: J D
authors.initials: JD
authors.lastname: Wark
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D010329:Patella / Q000000981:diagnostic imaging; D013177:Sports; D013710:Tendons / Q000000981:diagnostic imaging*; D014463:Ultrasonography