Conversion to Hip Arthroplasty After Internal Fixation Failure in an Intertrochanteric Femoral Fracture: A Case Report.

Intertrochanteric femoral fractures are mainly managed by internal fixation. However, failures such as over-telescoping, cut-out, nonunion, or implant failure can occur, especially in osteoporotic elderly patients. We report the case of a patient in whom we performed artificial hip replacement surgery after fixation failure following internal fixation of an intertrochanteric femoral fracture. We report the case of an 85-year-old woman who sustained a left intertrochanteric femoral fracture treated with a dynamic hip screw (DHS). One week postoperatively, radiographs revealed over-telescoping of the lag screw. The patient did not complain of pain, but she underwent conversion to cemented bipolar hemiarthroplasty under general anesthesia. One possible cause of over-telescoping of the lag screw after surgery was that the longitudinal fracture line in the calcar of the proximal bone fragment, as seen in the initial CT image, may have extended horizontally at the neck level. During surgery, a fracture at the same site caused the anterior medial fragment to fail, resulting in a coronal shear fracture and fixation failure. When a longitudinal fracture line is observed in the calcar of the proximal fragment, it is necessary to keep in mind that it may extend horizontally at the neck level.