Interprosthetic Fractures

The current literature does not offer a classification system for interprosthetic fractures. In these situations the fracture around the Total Hip Arthroplasty (THA) and the Total Knee Arthroplasty (TKA) can be classified according to the Vancouver[1] or Lewis and Rorabeck classification[2]. If the fracture occurs around or just distal to the hip stem the Vancouver classification can be used. If the fracture occurs more distal, around or just proximal to the knee prosthesis the Lewis and Rorabeck classification can be used.

Surgeons Tip
The length of the implant is important for an adequate fixation of interprosthetic fractures. To avoid stress risers the implant should overlap the hip or knee stem by a minimum of 4-6 cm.
 
[1] Duncan CP, Masri BA. Fractures of the femur after hip replacement. Instr Course Lect. 1995; 44:293-304
[2] Rorabeck CH, Taylor JW. Classification of periprosthetic fractures complicating total knee arthroplasty. Orthop Clin North Am1999; 30:209-214