Imaging description

Periprosthetic fractures involving the femur in the setting of hip arthroplasty are not rare. Periprosthetic acetabular fractures in the setting of arthroplasty are rare. Periprosthetic femur fractures are classified using the Vancouver classification system since it is reproducible and helps determine the type of treatment to be used. Fractures can occur at or about the femoral component or distal to the femoral component (Figure 53.1). They are readily detected on radiographs. A faint longitudinal linear lucency seen about the femoral stem tip in the immediate post-operative period may represent an artifact or longitudinal fracture; however, it can be treated conservatively (Figure 53.2).

Importance

Lesser trochanter and greater trochanter periprosthetic fractures are usually treated conservatively while femoral shaft perihardware fractures are treated with reduction and internal fixation (as long as the prosthesis is not loose). If there is hardware loosening present in addition to the fracture, then a revision arthoplasty with or without a graft is performed. A faint longitudinal linear lucency seen about the femoral stem tip in the immediate post-operative period may represent an artifact; however, it can be treated conservatively as well.

Typical clinical scenario

A 70-year-old female with a history of a right total hip arthroplasty 4 months ago presents with sudden onset of hip and right leg pain after a fall. She is unable to bear weight on the right leg. Radiographs demonstrate a femoral shaft fracture about the femoral stem of the right hip prosthesis. There is no evidence of perihardware loosening, and she has no clinical evidence of infection. The fracture was treated with reduction and interval fixation.

Teaching point

Trochanteric periprosthetic fractures are usually treated conservatively. Femoral shaft periprosthetic fractures in well-fixed prostheses usually require reduction and internal fixation with or without a graft. Loosened prostheses with a femoral shaft fracture generally require a revision arthroplasty. A faint longitudinal linear lucency seen about the femoral stem tip in the immediate postoperative period may represent an artifact; however, it can be treated conservatively.