Irreducible developmental dysplasia of the hip due to acetabular roof cartilage hypertrophy. Diagnostic sonography in 15 hips

SummaryIntroductionIrreducible developmental dysplasia of the hip (DDH) in newborns is a rare entity. The different obstacles preventing reduction have been described in the literature.HypothesisA clinical form of DDH with hypertrophy of the cartilage of the acetabular roof (acetabular bulge) can be reliably identified on ultrasound and should probably be defined as a separate entity.Materials and methodsFor the first time, the authors report their experience, a review of the literature and the radiographic description (ultrasound, arthrography MRI) of irreducible neonatal DDH due to hypertrophy of the cartilage of the acetabular roof (acetabular bulge) in 12 infants (15 hips).ResultsNeonatal sonography seems to be sufficient to identify this specific clinical entity without any additional work-up. This sonographic sign could help determine the therapeutic strategy earlier in this severe and complex form of DDH.Level of evidenceLevel IV. Diagnostic Study.