title: Prevalence of cam-type deformity and hip pain in elite ice hockey players before and after the end of growth.
abstract: BACKGROUND
  Elite-level sports activities have been associated with hip osteoarthritis and cam-type deformity.
  
  
  OBJECTIVE
  To analyze the appearance and prevalence of an abnormal cam-type deformity of the proximal femur and its potential association to hip pain in adolescent and young adult athletes.
  
  
  METHODS
  Cross-sectional study; Level of evidence, 3.
  
  
  METHODS
  A total of 77 elite-level male ice hockey players were evaluated with a questionnaire, clinical examination, and magnetic resonance imaging. The questionnaire and clinical examination were used to determine whether the hip being evaluated was symptomatic and what the internal rotation of the hip was. Magnetic resonance imaging was used to determine physeal status (open/closed) and α angle of the cranial half of the proximal femur using a standard clockface system.
  
  
  RESULTS
  The mean age of the patients was 16.5 years (range, 9-36 years); 15 of 77 (19.5%) athletes had a history of hip pain and a positive impingement test finding. The α angles were higher in athletes with closed physes versus open physes (58° vs 49°, respectively; P < .001). Symptomatic athletes had higher α angles compared with asymptomatic athletes at the 12-o'clock (52° vs 46°, respectively; P = .022), 1-o'clock (62° vs 52°, respectively; P < .001), and 2-o'clock (59° vs 50°, respectively; P < .001) positions. Internal rotation was significantly decreased in symptomatic compared with asymptomatic athletes (17° vs 23°, respectively). Higher α angles in the anterosuperior quadrant were significantly associated with decreased internal rotation.
  
  
  CONCLUSIONS
  The data suggest that playing ice hockey at an elite level during childhood is associated with an increased risk for cam-type deformity and hip pain after physeal closure.
authors.affiliation: Klaus A. Siebenrock, Department of Orthopedic Surgery, University of Bern, Inselspital, CH-3010 Bern, Switzerland. klaus.siebenrock@insel.ch.
authors.forename: Klaus A
authors.initials: KA
authors.lastname: Siebenrock
authors.forename: Iris
authors.initials: I
authors.lastname: Kaschka
authors.forename: Lars
authors.initials: L
authors.lastname: Frauchiger
authors.forename: Stefan
authors.initials: S
authors.lastname: Werlen
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Schwab
mesh_terms: D000293:Adolescent; D000328:Adult; D018771:Arthralgia / Q000453:epidemiology*; D002648:Child; D003430:Cross-Sectional Studies; D006621:Hip Joint / Q000254:growth & development*; D006688:Hockey / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D015207:Osteoarthritis, Hip / Q000453:epidemiology / Q000503:physiopathology; D015995:Prevalence; D013557:Switzerland / Q000453:epidemiology; D055815:Young Adult
keywords: cam-type deformity; femoroacetabular impingement; physeal growth