Femoral Stem Selection in Revision Total Hip Arthroplasty
The goals of revision total hip arthroplasty (THA) are the same as those of a primary procedure, Jeremy M. Gililland, MD, told attendees at ICJR’s 7th Annual Revision Hip & Knee Course:
- Obtain rigid initial stability
- Engage healthy bone proximally and/or distally
- Bypass areas of weakness
- Reconstruct biomechanics
A variety of femoral stems are available to achieve these goals, and in most cases, surgeons will use either a long cemented stem or one of the cementless stem options. In more extreme cases, Dr. Gililland said, surgeons can use an allograft prosthetic composite (APC), impaction grafting, or even a total femur.
The workhorse for classifying femoral defects when planning for a revision THA is the Paprosky Classification of Femoral Bone Loss, Dr. Gililland said, because it is easy to understand, it follows a logical progression from type I to type IV defects, and it is treatment oriented. Here are the options based on the Paprosky Classification:
Type I: The patient still has native femoral bone, and the surgeon should be able to use a primary THA stem. There’s no need for a revision stem if cancellous bone is present in the metaphysis and the calcar is supportive.
Type II: The surgeon should plan to use a fully porous coated or modular revision stem in patients with type II bone loss. The diaphysis has minimal damage, but the calcar is not supportive and little if any cancellous bone is present in the metaphysis.
Type IIIA: The stem options are the same as for a type II defect. The metaphysis is non-supportive, but more than 4 cm of distal fixation can be achieved at the isthmus.
Type IIIB: Fully porous coated stems typically fail with this type of defect, in which distal fixation at the isthmus is less than 4 cm. A modular revision stem can be used effectively, as can impaction grafting.
Type IV: A modular stem might be used, but in most cases, the femur is so ectatic, with so much metaphyseal and diaphyseal damage and so little chance of achieving reliable distal fixation, that APC, impaction grafting, and total femur are the most viable options.
Click the image above to watch Dr. Gililland’s presentation and learn more about stem selection in revision THA, including the advantages and disadvantages of fully porous coated monoblock stems and modular fluted and tapered stems.
Jeremy M. Gililland, MD, is an assistant professor in the Department of Orthopaedics at the University of Utah and chief of orthopaedic surgery at the George E. Wahlen Department of Veteran Affairs Medical Center in Salt Lake City.
Disclosures: Dr. Gililland has no disclosures relevant to this presentation.