Figure 3 A 67-year-old woman with injury from falling from a height. (A) The anteroposterior pelvic view reveals displaced superior and inferior pubic rami fractures on the right side, close to pubic symphysis. (B) Computed tomography (CT) construction scan of the pelvic ring demonstrates the overlapping superior and inferior pubic rami fracture and the compression sacral fracture due to the internal rotation of the pelvis. It concerns a type B1 lesion according to Tile classification on pelvic fracture. (C) The medial and lateral incisions of anterior pelvis ring. (D) Path planning of sacroiliac screw placement in S1 and S2. (E) Overall view of robot-aided sacroiliac screw manipulation. (F) Bone grafting via sacroiliac screw channel under C-arm fluoroscopy. There is a dense shadow in sacral ala, showing the injectable bone substitute. (G–I) Postoperative anteroposterior, inlet and outlet views. (J, K) Coronal and transverse CT views showing the positioning of the sacroiliac screw and the bone grafting. (L–O) Anteroposterior, inlet and outlet views and CT scan at 6 months after surgery showing the union of sacrum.