title: Are there sex-dependent differences in acetabular dysplasia characteristics?
abstract: BACKGROUND
  Many patients who undergo periacetabular osteotomy (PAO) for symptomatic acetabular dysplasia experience decreased pain and improved function, yet some experience inadequate clinical improvement. The etiologies of treatment failure have not been completely defined, and sex-dependent disease characteristics that may be associated with less pain relief are not understood.
  
  
  OBJECTIVE
  We sought to determine whether there were clinically important sex-specific differences between male and female patients undergoing PAO for acetabular dysplasia in terms of (1) clinical parameters (anthropomorphic traits and hip scores), (2) radiographic findings, and (3) intraoperative findings at the time of PAO, in particular findings potentially associated with femoroacetabular impingement (FAI) such as chondromalacia at the head-neck junction, impingement trough, or reduced head-neck offset.
  
  
  METHODS
  Between 2007 and 2012 we treated 245 patients (270 hips) with a PAO for symptomatic acetabular dysplasia. Of those, 16 patients (16 hips; 6%) had insufficient documentation for review in the medical record and another 49 patients (51 hips; 19%) met prespecified exclusion criteria, leaving 180 patients (203 hips; 75%) for analysis in this retrospective study. One hundred thirty-nine patients were females and 41 were males. Clinical data including patient demographics, physical examination, patient self-reported outcome scores, radiographic morphologic features, and intraoperative findings were collected prospectively as part of an institutional registry. Statistical analysis was performed with univariate and multivariate analyses.
  
  
  RESULTS
  Mean age was similar among sexes; however, BMI was greater in males compared with females (26 versus 24 kg/m(2); p = 0.002). Males had less hip ROM including internal rotation at 90° flexion (14° ± 13.8° versus 25° ± 16.2°; p = 0.001). Males had higher preoperative UCLA (7 ± 2, versus 6 ± 2; p = 0.02) and Harris hip scores (63 ± 15 versus 58 ± 16; p = 0.04). Radiographically, a crossover sign (88% versus 39%; p < 0.001) and posterior wall sign (92% versus 63%; p < 0.001) were more common in males. Males had greater alpha angles on the frog lateral (63° ± 15.3° versus 58° ± 16°; p = 0.04) and Dunn radiograph views (64° ± 15.5° versus 56° ± 14.8°; p = 0.02). The incidence of femoral head-neck chondromalacia (62% versus 82%; p = 0.03) and an impingement trough observed at surgery was greater in males (35% versus 17%; p = 0.01). Multivariate analysis showed differences between the sexes for reduced internal rotation in flexion, a higher Dunn alpha angle, increased incidence of a crossover sign, and a lower anterior center-edge angle.
  
  
  CONCLUSIONS
  There are sex-dependent, disease characteristic differences in patients with symptomatic acetabular dysplasia. Most notably, male patients have a greater prevalence of clinical, radiographic, and intraarticular findings consistent with concurrent FAI and instability and potentially a heightened risk of secondary FAI after PAO, however postoperative and long-term followup are needed to confirm these findings and it remains unclear which patients need surgical correction of the impingement and instability. Preoperative evaluation of acetabular dysplasia in males should at least include careful attention to factors associated with symptomatic FAI; however, further studies are needed to determine when surgical correction is needed.
authors: University of Kentucky, Lexington, KY, USA.
authors: Stephen T
authors: ST
authors: Duncan
authors: Ljiljana
authors: L
authors: Bogunovic
authors: Geneva
authors: G
authors: Baca
authors: Perry L
authors: PL
authors: Schoenecker
authors: John C
authors: JC
authors: Clohisy
mesh_terms: D000077:Acetabulum / Q000601:surgery*; D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D002648:Child; D005260:Female; D057925:Femoracetabular Impingement / Q000453:epidemiology* / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010027:Osteotomy; D010149:Postoperative Pain / Q000453:epidemiology; D012737:Sex Factors; D016896:Treatment Outcome; D055815:Young Adult
references: Iowa Orthop J. 2011;31:52-8
references: 22096420
references: Clin Orthop Relat Res. 2012 Feb;470(2):516-24
references: 22042717
references: J Bone Joint Surg Am. 2012 Nov 7;94(21):1959-66
references: 23138238
references: Clin Orthop Relat Res. 2008 Apr;466(4):782-90
references: 18288550
references: Clin Orthop Relat Res. 2007 Sep;462:115-21
references: 17589367
references: Orthopedics. 2011 Feb;34(2):86
references: 21323284
references: Clin Orthop Relat Res. 2009 Mar;467(3):666-75
references: 19048356
references: J Bone Joint Surg Am. 1995 Jul;77(7):985-9
references: 7608241
references: Clin Orthop Relat Res. 2009 Sep;467(9):2228-34
references: 19421831
references: Clin Orthop Relat Res. 2012 Dec;470(12):3508-14
references: 22926489
references: AJR Am J Roentgenol. 2007 Jun;188(6):1540-52
references: 17515374
references: J Bone Joint Surg Am. 2009 Sep;91(9):2113-23
references: 19723987
references: Clin Orthop Relat Res. 1999 Jun;(363):9-20
references: 10379300
references: Skeletal Radiol. 1997 Feb;26(2):75-81
references: 9060097
references: Clin Orthop Relat Res. 2011 Feb;469(2):447-53
references: 20848246
references: Clin Orthop Relat Res. 2011 Jan;469(1):188-99
references: 20596806
references: Clin Orthop Relat Res. 2003 Feb;(407):241-8
references: 12567152
references: J Pediatr Orthop. 2011 Jun;31(4):e30-5
references: 21572269
references: J Bone Joint Surg Am. 2006 Mar;88 Suppl 1 Pt 1:65-83
references: 16510801
references: Clin Orthop Relat Res. 2013 May;471(5):1602-14
references: 23354462
references: Clin Orthop Relat Res. 1986 Dec;(213):20-33
references: 3780093
references: J Orthop Res. 2008 Sep;26(9):1199-205
references: 18404737
references: J Bone Joint Surg Am. 2006 Sep;88(9):1920-6
references: 16951106
references: J Bone Joint Surg Br. 2007 Jun;89(6):721-4
references: 17613493
references: Clin Orthop Relat Res. 2009 Jan;467(1):128-34
references: 19034600
references: Br J Radiol. 1999 Apr;72(856):331-4
references: 10474491
references: Clin Orthop Relat Res. 1999 Jun;(363):93-9
references: 10379309
references: PM R. 2010 Oct;2(10):888-95
references: 20970757
references: Clin Orthop Relat Res. 2009 Aug;467(8):2041-52
references: 19381741
references: Clin Orthop Relat Res. 2006 Apr;445:181-5
references: 16456309
references: J Bone Joint Surg Am. 2011 May;93 Suppl 2:17-21
references: 21543683
references: Am J Sports Med. 2011 Jul;39 Suppl:72S-8S
references: 21709035
references: Rev Rhum Mal Osteoartic. 1961 Dec;28:643-52
references: 14464207
references: Clin Orthop Relat Res. 2008 Jul;466(7):1633-44
references: 18449617
references: J Bone Joint Surg Br. 2002 May;84(4):556-60
references: 12043778
references: Clin Orthop Relat Res. 1988 Jul;(232):26-36
references: 3383491
references: Instr Course Lect. 2001;50:229-38
references: 11372318
references: Instr Course Lect. 1986;35:119-28
references: 3819398
references: Instr Course Lect. 2001;50:239-45
references: 11372320
references: J Bone Joint Surg Am. 2009 Sep;91(9):2169-79
references: 19723994
references: Hip Int. 2007;17 Suppl 5:S22-8
references: 19197881
references: Clin Orthop Relat Res. 2012 Nov;470(11):2978-87
references: 22576934