Fig. 1

Radiographic images before revision surgery (a-f). a Crowe type IV DDH was found at the left hip before primary surgery. b-e Radiographic images of the patient’s left primary THA 1 day, 1 month, 3 months, 5 months postoperatively. f The radiographic examination of the patient’s left primary THA 14 months postoperatively shows that the distal stem is broken and the subtrochanteric osteotomy of the left femur is not healed