Ectopic ossification (EO) at the acetabular rim has been suggested to be associated with pincer impingement and to lead to ossification of the labrum. However, this has never been substantiated with histological, radiographic and MRI findings in large cohorts of patients. We hypothesized that it is more a bone apposition of the acetabular rim and that it occurs more frequently in coxa profunda (CP) hips. In the first part, a cohort of 20 hips with this suspected ectopic rim ossification (EO) pattern were identified. The radiographic features that could be associated with this ossification pattern were described and evaluated by a histologic examination of intra-operative samples taken from the rim trimming. In the second part, we assessed the prevalence of this ectopic ossification process in a cohort of 203 patients treated for FAI.Introduction
Materials and Methods
