Retroversion of the acetabulum

Abstract

We describe a little-known variety of hip dysplasia, termed 'acetabular retroversion', in which the alignment of the mouth of the acetabulum does not face the normal anterolateral direction, but inclines more posterolaterally. The condition may be part of a complex dysplasia or a single entity. Other than its retroversion, the acetabulum is sited normally on the side wall of the pelvis, and its articular surface is of normal extent and configuration. The retroverted orientation may give rise to problems of impingement between the femoral neck and anterior acetabular edge. We define the clinical and radiological parameters and discuss pathological changes which may occur in the untreated condition. A technique of management is proposed.

Prevalence of Radiographic Parameters Predisposing to Femoroacetabular Impingement in Young Asymptomatic Chinese and White Subjects

“…The ischial spine projection showed no significant difference in racial prevalence. The acetabular anteversion angle in this study was measured according to the method described by Stem et al 31 , at the midfemoral head level on the axial CT slices, whereas Reynolds et al 32 claimed that measurement of acetabular version at the superior part of the acetabulum was of greater value. With acetabular retroversion, the version angle is decreased at both levels, albeit less so at the midfemoral level 32 .…”

“…The acetabular anteversion angle in this study was measured according to the method described by Stem et al 31 , at the midfemoral head level on the axial CT slices, whereas Reynolds et al 32 claimed that measurement of acetabular version at the superior part of the acetabulum was of greater value. With acetabular retroversion, the version angle is decreased at both levels, albeit less so at the midfemoral level 32 . The measurement of central-instead of superior-acetabular anteversion can be considered a limitation; however, it does not sufficiently explain the observed inverse relationship between the crossover sign and the acetabular anteversion angle.…”

“…We included three parameters for the evaluation of the occurrence of acetabular retroversion in the racial groups: a decreased central acetabular anteversion angle (<15°), the crossover sign, and ischial spine projection [31][32][33]39 . We found that the prevalence of hips with a decreased acetabular anteversion angle was significantly higher in Chinese subjects (22% compared with 13% in white subjects), whereas the crossover sign was more prevalent in white subjects (30% compared with 6%).…”

CT assessment of herniation pits: prevalence, characteristics, and potential association with morphological predictors of femoroacetabular impingement

“…2). Acetabular orientation was measured between the line connecting the anterior and posterior acetabular margin and the sagittal plane, being the vertical on the intercapital centre line [27] (Fig. 2).…”

Mentoring in complex surgery: minimising the learning curve complications from peri-acetabular osteotomy

“…A value of greater than 1 indicates a lateralised centre of rotation and a value less than 1 a medialised centre of rotation compared to the contralateral side [10]. The version of the acetabulum was assessed according to Siebenrock et al [24] and Reynolds et al [20]. The degree of osteoarthritis pre-operatively and at latest review was graded according to the criteria of Tönnis [26].…”