Fig. 4

An illustrative case of loss-of-calcar support in postoperative 3D-CT follow-up. A: A 77-year-old female, diagnosed with 31A2.2 trochanteric fracture. B: Immediate AP fluoroscopy after operation, the arrow showed a large calcar fracture gap of the medial cortex (4.83 mm). C: Immediate lateral fluoroscopy after operation, the arrow showed a large calcar fracture gap of the anterior cortex (3.61 mm). D: Postoperative 3D CT image showed negative anteromedial cortical support. The arrow indicated posterior sagging of the head-neck fragment. E: In postoperative 14 months follow-up, the AP radiograph showed an apparent lateral sliding of the helical blade (10.5 mm)