title: Atraumatic tears of the ligamentum teres are more frequent in professional ballet dancers than a sporting population.
abstract: OBJECTIVE
  To compare the frequency of atraumatic ligamentum teres (LT) tear in professional ballet dancers with that of athletes, and to determine the relationship with clinical and imaging findings.
  
  
  METHODS
  Forty-nine male and female professional ballet dancers (98 hips) and 49 age and sex-matched non-dancing athletes (98 hips) completed questionnaires on hip symptoms and physical activity levels, underwent hip rotation range of movement (ROM) and hypermobility testing, and 3.0-Tesla magnetic resonance imaging (3 T MRI) on both hips to detect LT tears, acetabular labral tears, and articular cartilage defects, and to measure the lateral centre edge angles (LCE).
  
  
  RESULTS
  A higher frequency of LT tear was found in dancers (55 %) compared with athletes (22 %, P = 0.001). The frequency and severity of LT tears in dancers increased with older age (P = 0.004, P = 0.006, respectively). The Hip and Groin Outcome Score (HAGOS) pain scores or hip rotation ROM did not differ significantly among participants with normal, partial, or complete tears of LT (P > 0.01 for all). Neither the frequency of generalised joint hypermobility (P = 0.09) nor the LCE angles (P = 0.32, P = 0.16, left and right hips respectively) differed between those with and those without LT tear. In most hips, LT tear co-existed with either a labral tear or a cartilage defect, or both.
  
  
  CONCLUSIONS
  The higher frequency of atraumatic LT tears in professional ballet dancers suggests that the LT might be abnormally loaded in ballet, and caution is required when evaluating MRI, as LT tears may be asymptomatic. A longitudinal study of this cohort is required to determine if LT tear predisposes the hip joint to osteoarthritis.
authors.affiliation: School of Allied Health, La Trobe University, Bundoora, Victoria, 3086, Australia. suem@australianballet.com.au.|The Australian Ballet, 2 Kavanagh Street, Southbank, Victoria, 3006, Australia. suem@australianballet.com.au.
authors.forename: Susan
authors.initials: S
authors.lastname: Mayes
authors.affiliation: Department of Physiotherapy, Monash University, Frankston, Victoria, Australia.
authors.forename: April-Rose
authors.initials: AR
authors.lastname: Ferris
authors.affiliation: MIA East Melbourne Radiology, East Melbourne, Victoria, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Smith
authors.affiliation: School of Exercise and Nutrition Sciences, Deakin University, Burwood, Victoria, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Garnham
authors.affiliation: School of Allied Health, La Trobe University, Bundoora, Victoria, 3086, Australia.
authors.forename: Jill
authors.initials: J
authors.lastname: Cook
mesh_terms: D000293:Adolescent; D000328:Adult; D001265:Athletic Injuries / Q000000981:diagnostic imaging / Q000453:epidemiology*; D002358:Cartilage, Articular / Q000000981:diagnostic imaging / Q000293:injuries*; D003615:Dancing / Q000293:injuries*; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D000069590:Round Ligaments / Q000000981:diagnostic imaging / Q000293:injuries*; D013177:Sports; D055815:Young Adult
keywords: Ballet; Hip joint; Hypermobility; Lateral centre edge angle; Ligamentum teres; Magnetic resonance imaging