title: Correlation between coxa profunda and morphological parameters of acetabular coverage in a Japanese cohort: A CT study.
abstract: BACKGROUND
  Coxa profunda is generally considered an indicator of acetabular overcoverage. However, recent studies have opposed this view. The correlation between coxa profunda and acetabular overcoverage thus remains controversial. The purpose of this study was to investigate the prevalence of coxa profunda and the association between coxa profunda and acetabular coverage based on sex in Japanese subjects using computed tomography.
  
  
  METHODS
  We reviewed the computed tomography scans of 151 Japanese consecutive patients (302 hips) aged <50 years who underwent abdominopelvic computed tomography for symptoms unrelated to hip disease. Coxa profunda was diagnosed when the floor of the acetabular fossa touched or was medial to the ilioischial line. We measured the lateral center edge angle, acetabular roof obliquity angle, acetabular version, and anterior and posterior acetabular sector angles as parameters of acetabular coverage.
  
  
  RESULTS
  Coxa profunda was observed in 45.7% of all subjects, and was more common in females (63.0%) than in males (29.5%). We found no significant differences in the incidence of coxa profunda among subjects with dysplasia, overcoverage, and normal coverage. Males with coxa profunda showed significantly greater lateral center edge angle, anterior acetabular sector angle, and lower acetabular roof obliquity angle, whereas anterior and posterior acetabular sector angles were greater in all subjects and females with coxa profunda. Coxa profunda showed poor sensitivity (57.7%) and specificity (56.8%) for detecting overcoverage in all subjects.
  
  
  CONCLUSIONS
  Coxa profunda is a common radiographic feature in Japanese patients, especially in women. Coxa profunda may be less useful for diagnosing acetabular overcoverage because of its common occurrence with various hip morphologies and its poor specificity for detecting acetabular overcoverage. However, men with coxa profunda have greater acetabular coverage, so coxa profunda may contribute to acetabular coverage in men. We should take into account that coxa profunda may have different implications between the sexes.
authors.affiliation: Department of Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15 Kuramoto, Tokushima 770-8503, Japan. Electronic address: tomogoto@mbr.nifty.com.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Goto
authors.affiliation: Department of Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15 Kuramoto, Tokushima 770-8503, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Mineta
authors.affiliation: Department of Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15 Kuramoto, Tokushima 770-8503, Japan.
authors.forename: Keizo
authors.initials: K
authors.lastname: Wada
authors.affiliation: Department of Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15 Kuramoto, Tokushima 770-8503, Japan.
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Tamaki
authors.affiliation: Department of Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15 Kuramoto, Tokushima 770-8503, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Hamada
authors.affiliation: Department of Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15 Kuramoto, Tokushima 770-8503, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Takasago
authors.affiliation: Department of Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15 Kuramoto, Tokushima 770-8503, Japan.
authors.forename: Kosaku
authors.initials: K
authors.lastname: Higashino
authors.affiliation: Department of Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15 Kuramoto, Tokushima 770-8503, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Sairyo
mesh_terms: D000077:Acetabulum / Q000002:abnormalities* / Q000000981:diagnostic imaging*; D000328:Adult; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D006621:Hip Joint / Q000002:abnormalities / Q000000981:diagnostic imaging*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D007592:Joint Diseases / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D018570:Risk Assessment; D012737:Sex Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*