Fig. 1

Preoperative hip X-rays and CT images. a X-ray image of the front of the hip with the patient in a standing position, taken at a previous hospital 1 year earlier, showing severe posterior pelvic tilt. b X-ray image of the front of the hip with the patient in a supine position at first visit to our hospital, showing anterior dislocation of the hemi-arthroplasty and a posterior pelvic tilt. c Lumbar sagittal X-ray image of the patient in the supine position at first visit to our hospital, showing a wedge-shaped compression fracture of the fifth lumbar vertebra and lumbar lordosis. d Preoperative axial CT images, showing a small bone fragment, which suggested an acetabulum anterior bone fracture