title: The prevalence of radiographic hip abnormalities in elite soccer players.
abstract: BACKGROUND
  Hip injuries, both intra- and extra-articular, are becoming a more commonly recognized, diagnosed, and treated injury in athletes of all competitive levels. Our goal is to establish a previously undefined value in this athletic population--the prevalence of radiographic hip abnormalities in elite soccer athletes.
  
  
  OBJECTIVE
  To provide a foundation for the future body of literature regarding hip pathologic abnormalities and "at-risk" hips in athletes of all ages and levels of participation.
  
  
  METHODS
  Descriptive epidemiology study.
  
  
  METHODS
  We retrospectively reviewed the anteroposterior pelvis and frog-leg lateral radiographs of 95 elite male and female soccer players to determine the prevalence of hip abnormalities. Athletes with a history of hip or groin injuries were included. Multiple radiographic parameters were used to assess the presence of cam and pincer-type femoroacetabular impingement. Measurements were conducted by a blinded, sports medicine fellowship-trained orthopaedic surgeon with experience in treating hip disorders.
  
  
  RESULTS
  In total, 72% (54/75) of male and 50% (10/20) of female players demonstrated some evidence of radiographic hip abnormality. Cam lesions were present in 68% (51/75) of men (76.5% [39/51] bilateral involvement) and 50% (10/20) of women (90% [9/10] bilateral involvement). Pincer lesions were present in 26.7% (20/75) of men and 10% (2/20) of women. The average male alpha angle overall was 65.6°. Cam-positive hips averaged 70.7°. The average female alpha angle overall was 52.9°, with cam-positive hips averaging 60.8°.
  
  
  CONCLUSIONS
  The prevalence of radiographic hip abnormalities in elite soccer athletes is considerable, particularly in young male athletes. The establishment of the prevalence of these findings represents the first step in identifying the relationship between radiographic abnormalities and injuries of the hip and groin in athletes.
authors.affiliation: Santa Monica Orthopaedic and Sports Medicine Group, 2020 Santa Monica Blvd, Fourth Floor, Santa Monica, CA 90404, USA.
authors.forename: Michael B
authors.initials: MB
authors.lastname: Gerhardt
authors.forename: Alex A
authors.initials: AA
authors.lastname: Romero
authors.forename: Holly Jacinda
authors.initials: HJ
authors.lastname: Silvers
authors.forename: David J
authors.initials: DJ
authors.lastname: Harris
authors.forename: Diane
authors.initials: D
authors.lastname: Watanabe
authors.forename: Bert R
authors.initials: BR
authors.lastname: Mandelbaum
mesh_terms: D000328:Adult; D005260:Female; D006615:Hip / Q000000981:diagnostic imaging* / Q000473:pathology*; D025981:Hip Injuries / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D008297:Male; D015995:Prevalence; D011859:Radiography; D012189:Retrospective Studies; D012916:Soccer / Q000293:injuries*; D055815:Young Adult