Pollet V, Bonsel J, Ganzeboom B, et al. - Researchers distinguished morphological variants in hip joint development that are predictive of a poor outcome. A retrospectively reviewed was conducted to enroll a total of 135 patients who developed avascular necrosis (AVN) after developmental dysplasia of the hip (DDH) treatment, either by closed and/or open reduction, at a single institution between 1984 and 2007 with a minimal follow-up of eight years. They retrieved standard pelvis radiographs obtained at ages one, two, three, five, and eight years, and at the latest follow-up. The type of AVN on all radiographs was ascertained by using the Bucholz-Ogden classification. At a very young age, specific morphological characteristics on pelvis radiographs of AVN hips were predictive for poor outcomes. An overall stronger association to Bucholz-Ogden types 2-3-4 with the exception of two modes was observed at age two and five years, linked to AVN type 1.