title: Similar Prevalence of Acetabular Labral Tear in Professional Ballet Dancers and Sporting Participants.
abstract: OBJECTIVE
  To compare the prevalence of acetabular labral tear in male and female professional ballet dancers with age-matched and sex-matched sporting participants and to determine the relationship to clinical findings and cartilage defects.
  
  
  METHODS
  Case-control study.
  
  
  METHODS
  Clinical and radiology practices.
  
  
  METHODS
  Forty-nine (98 hips) male and female professional ballet dancers (current and retired) with median age 30 years (range: 19-64 years) and 49 (98 hips) age-matched and sex-matched sporting participants.
  
  
  METHODS
  Group (ballet or sports), sex, age, hip cartilage defects, history of hip pain, Hip and Groin Outcome Score, passive hip internal rotation (IR), and external rotation range of movement (ROM).
  
  
  METHODS
  Labral tear identified with 3T magnetic resonance imaging (MRI).
  
  
  RESULTS
  Labral tears were identified in 51% of all 196 hips. The prevalence did not differ significantly between the ballet and sporting participants (P = 0.41) or between sexes (P = 0.34). Labral tear was not significantly associated with clinical measures, such as pain and function scores or rotation ROM (P > 0.01 for all). Pain provocation test using IR at 90° of hip flexion had excellent specificity [96%, 95% confidence intervals (CIs), 0.77%-0.998%] but poor sensitivity (50%, 95% CI, 0.26%-0.74%) for identifying labral tear in participants reporting hip pain. Older age and cartilage defect presence were independently associated with an increased risk of labral tear (both P < 0.001).
  
  
  CONCLUSIONS
  The prevalence of labral tear in male and female professional ballet dancers was similar to a sporting population. Labral tears were not associated with clinical findings but were related to cartilage defects, independent of aging.
  
  
  CONCLUSIONS
  Caution is required when interpreting MRI findings as labral tear may not be the source of the ballet dancer's symptoms.
authors.affiliation: *The Australian Ballet, Victoria, Australia; †Department of Physiotherapy, School of Allied Health, La Trobe University, Bundoora 3086, Australia; ‡Department of Physiotherapy School of Primary Health Care Faculty of Medicine, Nursing and Health Sciences, Monash University, Victoria, Australia; §MIA East Melbourne Radiology, East Melbourne, Victoria, Australia; and ‖School of Exercise and Nutrition Sciences, Deakin University, Victoria, Australia.
authors.forename: Susan
authors.initials: S
authors.lastname: Mayes
authors.forename: April-Rose
authors.initials: AR
authors.lastname: Ferris
authors.forename: Peter
authors.initials: P
authors.lastname: Smith
authors.forename: Andrew
authors.initials: A
authors.lastname: Garnham
authors.forename: Jill
authors.initials: J
authors.lastname: Cook
mesh_terms: D000328:Adult; D056352:Athletes; D001265:Athletic Injuries / Q000000981:diagnostic imaging / Q000453:epidemiology*; D002358:Cartilage, Articular / Q000000981:diagnostic imaging / Q000293:injuries*; D016022:Case-Control Studies; D003615:Dancing / Q000293:injuries*; D005260:Female; D025981:Hip Injuries / Q000000981:diagnostic imaging / Q000453:epidemiology*; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D015995:Prevalence; D016059:Range of Motion, Articular; D012680:Sensitivity and Specificity; D055815:Young Adult