Fig. 7A–B

(A) Bilateral protrusio acetabuli in a 25-year old female patient with an underlying diagnosis of osteogenesis imperfecta with complaints of limited ROM until a fatigue fracture of the acetabular fossa. MR arthrography revealed mild cartilage injury around the medial contour of the head. (B) Three-year postoperative radiographs demonstrated a lateralized acetabulum with a horizontal roof and healing of the fatigue fracture; however, the craniomedial joint space remained narrow.