title: Sex differences of hip morphology in young adults with hip pain and labral tears.
abstract: OBJECTIVE
  To compare hip morphology between young men and women who presented with hip pain and labral tears.
  
  
  METHODS
  A retrospective review of our hip arthroscopy registry from March 2008 to June 2010 was completed. We identified 217 patients (249 hips) who were between the ages of 18 to 30 years. The inclusion criteria were (1) insidious-onset hip pain or worsening pain after low-energy sports trauma, (2) positive hip impingement sign, (3) Tönnis grades 0 to 1, (4) magnetic resonance imaging showing labral tear, and (5) primary hip arthroscopy confirming labral tear. Forty-five patients (52 hips) were excluded for the following reasons: (1) revision hip arthroscopy, (2) high-energy hip trauma, (3) history of surgery involving the femur or pelvis, (4) previous fractures of the femur or pelvis, (5) Tönnis grades 2 or above, (6) proliferative disease of the hip (i.e., synovial chondromatosis, pigmented villonodular synovitis), (7) neuromuscular disease (i.e., cerebral palsy), and (8) deformities related to Legg-Calvé-Perthes disease or developmental dysplasia of the hip. Therefore, the cohort study group included 105 (61%) men (123 [62.4%] hips) and 67 (39%) women (74 [37.6%] hips). Sex comparisons were made for the following variables measured on preoperative hip computed tomography scans: alpha angle, acetabular version, femoral version, lateral center-edge angle, and neck-shaft angle.
  
  
  RESULTS
  Women had smaller alpha angles (47.8°v 63.6°, P < .001), increased acetabular version (17.3°v 13.9°, P < .001), and increased femoral anteversion (14.4°v 12.1°, P = .05).
  
  
  CONCLUSIONS
  In young adults with hip pain and labral tears, women have smaller alpha angles and hips that are generally more anteverted. Therefore, in women, cam lesions may be more subtle, preoperative hip version analyses should be encouraged, and rim trimming may need to be cautiously planned to avoid increasing contact stresses at weight-bearing areas after such a procedure.
  
  
  METHODS
  Level III, retrospective comparative study.
authors.affiliation: Department of Orthopedic Surgery, Meir General Hospital, Sapir Medical Center, Kfar Saba, Israel. iftachhetsroni@gmail.com
authors.forename: Iftach
authors.initials: I
authors.lastname: Hetsroni
authors.forename: Katrina
authors.initials: K
authors.lastname: Dela Torre
authors.forename: Gavin
authors.initials: G
authors.lastname: Duke
authors.forename: Stephen
authors.initials: S
authors.lastname: Lyman
authors.forename: Bryan T
authors.initials: BT
authors.lastname: Kelly
mesh_terms: D000077:Acetabulum / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D000293:Adolescent; D000328:Adult; D000886:Anthropometry; D018771:Arthralgia / Q000209:etiology*; D001182:Arthroscopy; D001265:Athletic Injuries / Q000601:surgery; D001696:Biomechanical Phenomena; D003646:Debridement; D005260:Female; D005270:Femur Head / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D051445:Fibrocartilage / Q000000981:diagnostic imaging / Q000293:injuries* / Q000473:pathology / Q000601:surgery; D005684:Gait; D025981:Hip Injuries / Q000601:surgery*; D006621:Hip Joint / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D012727:Sex Characteristics; D014057:Tomography, X-Ray Computed; D016474:Weight-Bearing; D055815:Young Adult