[How I explore... protrusio acetabuli in children].

Protrusio acetabuli is a clinical entity with variable clinical presentation consisting of a medial deviation of the acetabulum in the pelvic direction. Qualified as a silent deformity in view of its asymptomatic nature until the onset of early degenerative changes, the patient will present with progressive joint pain and stiffness until the development of secondary osteoarthritis. In view of the potentially destructive primary causes associated with the development of secondary protrusion acetabuli, the radiological demonstration of this pathology in young patients cannot be neglected and should lead to the investigation of the underlying pathologies associated with this anomaly. This entity must generate regular clinical and radiological monitoring, and potentially multidisciplinary approach in the event of the appearance of diagnostic criteria for Marfan syndrome, which may vary over time and across individuals.