title: Are maturation, growth and lower extremity alignment associated with overuse injury in elite adolescent ballet dancers?
abstract: OBJECTIVE
  To identify growth, maturation and biomechanical risk factors for overuse injury in elite adolescent ballet dancers.
  
  
  METHODS
  Maturation (Tanner scale), growth (foot length change) and age at onset of menarche were recorded in elite adolescent ballet dancers. A modified knee valgus angle and lateral tilt of the pelvis were measured using 2D video during two dance movements (fondu, temps levé) to quantify lower extremity alignment. Overuse dance injuries were recorded by a physiotherapist. The injury rate ratio (RR) associated with each variable was estimated using over-dispersed Poisson regression modelling.
  
  
  RESULTS
  Changes in right foot length (RR = 1.41, CI = 0.93-2.13), right knee angles during the fondu (RR = 0.68, CI = 0.45-1.03) and temps levé (RR = 0.72, CI = 0.53-0.98), and pelvic angles during the temps levé on the left (RR = 0.52, CI = 0.30-0.90) and fondu on the right (RR = 1.28, CI = 0.91-1.80) were associated with substantial changes in injury risk.
  
  
  CONCLUSIONS
  Rate of growth in elite adolescent ballet dancers is likely associated with an increase in risk of lower extremity overuse injury and better right lower extremity alignment is likely associated with a reduction in risk of right lower extremity overuse injury.
authors.affiliation: AUT University, Sports Performance Research Institute NZ (SPRINZ), 17 Antares Place, Auckland, New Zealand. Electronic address: erin@westmerepilates.co.nz.
authors.forename: Erin
authors.initials: E
authors.lastname: Bowerman
authors.affiliation: AUT University, Sports Performance Research Institute NZ (SPRINZ), 17 Antares Place, Auckland, New Zealand. Electronic address: chris.whatman@aut.ac.nz.
authors.forename: Chris
authors.initials: C
authors.lastname: Whatman
authors.affiliation: AUT University, Sports Performance Research Institute NZ (SPRINZ), 17 Antares Place, Auckland, New Zealand. Electronic address: nigel.harris@aut.ac.nz.
authors.forename: Nigel
authors.initials: N
authors.lastname: Harris
authors.affiliation: Australian Catholic University, 115 Victoria Parade, Fitzroy, Victoria 3065, Australia. Electronic address: elizabeth.bradshaw@acu.edu.au.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Bradshaw
authors.affiliation: Australian Ballet School, 2 Kavanagh Street, Southbank, Victoria 3006, Australia.
authors.forename: Janet
authors.initials: J
authors.lastname: Karin
mesh_terms: D000293:Adolescent; D001696:Biomechanical Phenomena; D012090:Cumulative Trauma Disorders / Q000453:epidemiology*; D003615:Dancing; D005260:Female; D033023:Foot Joints / Q000502:physiology; D006801:Humans; D015994:Incidence; D007719:Knee Joint / Q000502:physiology; D035002:Lower Extremity / Q000502:physiology*; D008297:Male; D010388:Pelvis / Q000502:physiology; D012741:Sexual Maturation
keywords: Age; Alignment; Dance; Growth; Injury; Lower extremity; Maturation; Overuse; Risk factors; Youth