CORRInsights®: Acetabular Version Increases After Closure of the Triradiate Cartilage Complex
In the current study, Albers and colleagues report results of their prospective, longitudinal cohort series that describes acetabular development in 65 healthy children during adolescence. Their data add substantially to an area where little has been published to date. The authors use an MRI-based technique that allows greater ability to detect the cartilaginous portions of the acetabular rim in skeletally immature patients, where pincer lesions may arise, which was not possible in previous CT-based studies [4, 7]. Consistent with these previous CT-based studies [4, 7], Albers and colleagues find that acetabular version increases with advancing skeletal maturity, and that this process happens over a relatively narrow timeframe near physeal closure of the triradiate cartilage complex (TCC). However, unlike the CT-based studies, their data suggest that the acetabular depth-width ratio and femoral head coverage remain relatively constant during acetabular development, which may reflect the more sensitive radiologic technique utilized in their methodology that allows accurate detection and measurement of the cartilaginous portions of the acetabular rim. These data imply normal acetabular changes that occur around the time of TCC closure may result from a rotational mechanism rather than relative growth differences between the anterior and posterior walls.