title: Doppler ultrasound and tibial tuberosity maturation status predicts pain in adolescent male athletes with Osgood-Schlatter's disease: a case series with comparison group and clinical interpretation.
abstract: BACKGROUND
  The pathogenesis of the Osgood-Schlatter's disease (OSD) is still debated. The fragmentation of the ossification centre has been questioned as a definitive sign of OSD and has been seen as a normal development of the anterior tibial tubercle (ATT).
  
  
  OBJECTIVE
  It is unknown if such changes are present in the presumed pathological tendon insertion seen in OSD, nor the relation of Doppler-positive changes to pain on clinical examination.
  
  
  METHODS
  A prospective analysis was carried out on 20 consecutive symptomatic male athletes (13.9 years±1.3) and a comparison group of asymptomatic subjects. All underwent a comparative clinical assessment and ultrasound with colour Doppler scan on both knees. Subjective pain was recorded with a visual analogue scale (VAS) during provocative manoeuvres: palpation, resisted contraction and single leg squat.
  
  
  RESULTS
  Positive Doppler US (within the distal end of the patellar tendon) was associated with higher pain on palpation (47±24.5 vs 18±11.4, p<0.01) and resisted static contraction (59±20.2 vs 27±12.5, p<0.001) compared with Doppler-negative subjects. No Doppler activity was found in the comparison group. VAS for palpation and resisted contraction of the athletes graded as stage 2 (51.1±22.0 and 60.0±21.2) were significantly higher than stage 3 (17.8±12.0 and 18.9±16.9) and stage 4 (15.0±7.1 and 25.0±7.1; p<0.01).
  
  
  CONCLUSIONS
  More painful OSD is associated with the presence of neo-vessels. This may be linked with a particular stage of ATT maturation and applied compressive forces. A Doppler ultrasound scan adds practical information to develop the care plan of the patient.
authors.affiliation: Centre de Biologie et de Medecine du Sport de Pau, Centre Hospitalier Pau, Pau, France. matthieusailly@yahoo.fr
authors.forename: Matthieu
authors.initials: M
authors.lastname: Sailly
authors.forename: Rod
authors.initials: R
authors.lastname: Whiteley
authors.forename: Amanda
authors.initials: A
authors.lastname: Johnson
mesh_terms: D000293:Adolescent; D000367:Age Factors; D018771:Arthralgia / Q000000981:diagnostic imaging / Q000209:etiology*; D056352:Athletes; D016022:Case-Control Studies; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D055034:Osteochondrosis / Q000000981:diagnostic imaging / Q000473:pathology*; D010147:Pain Measurement; D011446:Prospective Studies; D013977:Tibia / Q000000981:diagnostic imaging / Q000473:pathology*; D018615:Ultrasonography, Doppler, Color