title: The prevalence of radiographic findings of structural hip deformities in female collegiate athletes.
abstract: BACKGROUND
  Structural deformities of the hip, including femoroacetabular impingement (FAI) and acetabular dysplasia, often limit athletic activity. Previous studies have reported an increased prevalence of radiographic cam FAI in male athletes, but data on the prevalence of structural hip deformities in female athletes are lacking.
  
  
  OBJECTIVE
  (1) To quantify the prevalence of radiographic FAI deformities and acetabular dysplasia in female collegiate athletes from 3 sports: volleyball, soccer, and track and field. (2) To identify possible relationships between radiographic measures of hip morphologic characteristics and physical examination findings.
  
  
  METHODS
  Cross-sectional study; Level of evidence, 3.
  
  
  METHODS
  Anteroposterior (AP) pelvis and frog-leg lateral radiographs were obtained from 63 female athletes participating in Division I collegiate volleyball, soccer, and track and field. Lateral center edge angle (LCEA) and acetabular index were measured on AP films. Alpha angle and head-neck offset were measured on frog-leg lateral films. Pain during the supine impingement examination and hip rotation at 90° of flexion were recorded. Random-effects linear regression was used for group comparisons and correlation analyses to account for the lack of independence of observations made on left and right hips.
  
  
  RESULTS
  Radiographic cam deformity (alpha angle >50° and/or head-neck offset <8 mm) was found in 48% (61/126) of hips. Radiographic pincer deformity (LCEA >40°) was noted in only 1% (1/126) of hips. No hips had radiographic mixed FAI (at least 1 of the 2 cam criteria and LCEA >40°). Twenty-one percent (26/126) of hips had an LCEA <20°, indicative of acetabular dysplasia, and an additional 46% (58/126) of hips had borderline dysplasia (LCEA ≥20° and ≤25°). Track and field athletes had significantly increased alpha angles (48.2° ± 7.1°) compared with the soccer players (40.0° ± 6.8°; P < .001) and volleyball players (39.1° ± 5.9°; P < .001). There was no significant difference in the LCEA (all P > .914) or the prevalence of dysplasia (LCEA <20°) between teams (all P > .551). There were no significant correlations between the radiographic measures and internal rotation (all P > .077). There were no significant differences (all P > .089) in radiographic measures between hips that were painful (n = 26) during the impingement examination and those that were not.
  
  
  CONCLUSIONS
  These female athletes had a lower prevalence of radiographic FAI deformities compared with previously reported values for male athletes and a higher prevalence of acetabular dysplasia than reported for women in previous studies.
authors.affiliation: Department of Orthopaedics, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Ashley L
authors.initials: AL
authors.lastname: Kapron
authors.affiliation: Department of Orthopaedics, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Peters
authors.affiliation: Department of Orthopaedics, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Stephen K
authors.initials: SK
authors.lastname: Aoki
authors.affiliation: Department of Orthopaedics, University of Utah, Salt Lake City, Utah, USA.
authors.forename: James T
authors.initials: JT
authors.lastname: Beckmann
authors.affiliation: Department of Orthopaedics, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Jill A
authors.initials: JA
authors.lastname: Erickson
authors.affiliation: Department of Orthopaedics, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Mike B
authors.initials: MB
authors.lastname: Anderson
authors.affiliation: Department of Orthopaedics, University of Utah, Salt Lake City, Utah, USA chris.pelt@hsc.utah.edu.
authors.forename: Christopher E
authors.initials: CE
authors.lastname: Pelt
mesh_terms: D000293:Adolescent; D056352:Athletes; D003430:Cross-Sectional Studies; D005260:Female; D057925:Femoracetabular Impingement / Q000000981:diagnostic imaging* / Q000453:epidemiology; D006617:Hip Dislocation / Q000000981:diagnostic imaging* / Q000453:epidemiology; D006621:Hip Joint / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D010146:Pain / Q000453:epidemiology / Q000209:etiology; D010388:Pelvis / Q000000981:diagnostic imaging; D015995:Prevalence; D011859:Radiography; D016059:Range of Motion, Articular; D012399:Rotation; D012916:Soccer; D014142:Track and Field; D054798:Volleyball; D055815:Young Adult
keywords: acetabular dysplasia; female athletes; femoroacetabular impingement; football (soccer); hip; track and field; volleyball