First reported case of developmental dysplasia of the hips in a child with 3M syndrome: a case report

3M syndrome is a rarely inherited autosomal recessive disorder caused by mutations in cullin-7 (CUL7), obscurin-like 1 (OBSL1), and coiled-coil domain containing protein 8 (CCDC8). It is associated with multiple dysmorphic features, including characteristic facial dysmorphism (a face that is triangular, full lips, frontal bossing, a nasal tip that is fleshy, long philtrum, protruding ears and macrocephaly), severe growth retardation prenatally and postnatally and normal intelligence. Although there are multiple skeletal manifestations of the syndrome, such as joint laxity, there is no mention of developmental dysplasia of the hip (DDH) to be associated with it anywhere in the literature. Therefore, we present the first case of bilateral DDH in a patient with 3M syndrome, which was managed similarly to other DDH cases with operative reduction, pelvic osteotomies, and femoral shortening, with a satisfactory outcome after 3 years of follow-up.