title: Doppler ultrasonography of the anterior knee tendons in elite badminton players: colour fraction before and after match.
abstract: BACKGROUND
  Anterior knee tendon problems are seldom reported in badminton players although the game is obviously stressful to the lower extremities.
  
  
  OBJECTIVE
  Painful anterior knee tendons are common among elite badminton players. The anterior knee tendons exhibit colour Doppler activity. This activity increases after a match. Painful tendons have more Doppler activity than tendons without pain.
  
  
  METHODS
  Cohort study.
  
  
  METHODS
  72 elite badminton players were interviewed about training, pain and injuries. The participants were scanned with high-end ultrasound equipment. Colour Doppler was used to examine the tendons of 64 players before a match and 46 players after a match. Intratendinous colour Doppler flow was measured as colour fraction (CF). The tendon complex was divided into three loci: the quadriceps tendon, the proximal patellar tendon and the insertion on the tibial tuberosity.
  
  
  RESULTS
  Interview: Of the 72 players, 62 players had problems with 86 tendons in the lower extremity. Of these 86 tendons, 48 were the anterior knee tendons. Ultrasound: At baseline, the majority of players (87%) had colour Doppler flow in at least one scanning position. After a match, the percentage of the knee complexes involved did not change. CF increased significantly in the dominant leg at the tibial tuberosity; single players had a significantly higher CF after a match at the tibial tuberosity and in the patellar tendon both before and after a match. Painful tendons had the highest colour Doppler activity.
  
  
  CONCLUSIONS
  Most elite badminton players had pain in the anterior knee tendons and intratendinous Doppler activity both before and after match. High levels of Doppler activity were associated with self-reported ongoing pain.
authors.affiliation: The Parker Institute, Frederiksberg Hospital, Denmark. merete.koenig@frh.regionh.dk
authors.forename: M J
authors.initials: MJ
authors.lastname: Koenig
authors.forename: S
authors.initials: S
authors.lastname: Torp-Pedersen
authors.forename: M I
authors.initials: MI
authors.lastname: Boesen
authors.forename: C C
authors.initials: CC
authors.lastname: Holm
authors.forename: H
authors.initials: H
authors.lastname: Bliddal
mesh_terms: D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000098:blood supply / Q000000981:diagnostic imaging; D000070598:Anterior Cruciate Ligament Injuries; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000000981:diagnostic imaging*; D008297:Male; D010146:Pain / Q000209:etiology; D017847:Patellar Ligament / Q000098:blood supply / Q000000981:diagnostic imaging / Q000293:injuries*; D015865:Racquet Sports / Q000293:injuries*; D018608:Ultrasonography, Doppler; D055815:Young Adult