What is the ideal treatment for distal femoral periprosthetic fractures?
Click Here to Manage Email Alerts
Click here to read the Cover Story, "Novel techniques advance periprosthetic fracture care."
Intramedullary nail fixation
Most of the surgeons in our group have a strong preference for using intramedullary fixation for distal femoral periprosthetic fractures.
Fortunately, most of these cases have enough bone stock on the femoral flange to allow intramedullary fixation, and few of these have a “closed box” total knee arthroplasty. We see more than 50 to 70 distal femur periprosthetic fractures a year, and only one or two a year have a loose femoral flange or inadequate bone stock for fixation.
Two studies have shown a relatively low failure rate using intramedullary fixation even in very distal variations (fracture at or distal to the flange) of these difficult fractures, with immediate weight-bearing as tolerated in most cases. We occasionally add a plate (nail-plate construct), but do not find this helpful if we can get four to five or more distal cortices with the locking screws. Nail-plate constructs are likely most helpful in preventing fixation failure or progressive loss of alignment, both of which were low in a study from myself and colleagues as well as a study from Noelle L. Van Rysselberghe, MD, and colleagues. We worry that the routine use of a nail-plate construct can increase the infection rate (additional incisions and surgical time) and nonunion rate (extremely stiff constructs), although there is not enough data out on these relatively newer constructs for direct comparison to retrograde nailing alone.
We try to avoid conversion to a distal femoral replacement. Most of the bigger studies and meta-analyses do not show a mobility or activity benefit vs. fracture fixation. In addition, immediate bulk arthroplasty in trauma patients that are not optimized for arthroplasty has an increased risk of infection. A significant number of these infected distal femoral replacements go on to amputation, an outcome that is not discussed in most of the papers supporting the more liberal use of arthroplasty in these fractures.
As in many fractures, there are a few technique steps that are critical to success in intramedullary nailing of distal femoral periprosthetic fractures. It is important to use a dedicated “distal femur nail” that allows multiple multiplanar locking screw fixation. It is also advantageous to position the nail so that the distal most screw is abutting the femoral flange. Finally, most modern distal femoral nails have an option to “lock” the screws to the nail to achieve fixed angle fixation, and we think this is advantageous in these fractures.
- References:
- Van Rysselberghe NL, et al. J Orthop Trauma. 2024;doi:10.1097/BOT.0000000000002730.
- Virkus WV, et al. J Orthop Trauma. 2022;doi:10.1097/BOT.0000000000002352.
- Wadhwa H, et al. J Orthop Trauma. 2022;doi:10.1097/BOT.0000000000002141.
Walter W. Virkus, MD, is the director of orthopedic trauma and professor of orthopedic surgery at the Indiana University School of Medicine in Indianapolis.
Dual construct fixation
Periprosthetic fractures about a TKA can be a devastating and challenging clinical scenario. First and foremost, when assessing the ideal construct or treatment algorithm, implant stability with surrounding bone stock/quality must be determined. For those fracture patterns surrounding an unstable, loose implant with poor bone stock, then fixation is not ideal; here, in my opinion, a distal femoral replacement is the treatment of choice to allow for immediate weight-bearing.
For stable, well-fixed implants, fixation is the preferred treatment modality with the goals of allowing immediate weight-bearing and early mobilization, especially in the geriatric patient population. For simple fracture patterns, especially those occurring above the anterior flange of the femoral component, isolated retrograde intramedullary nail or lateral locked plating can offer immediate weight-bearing and reliable healing rates.
For more complex periprosthetic fracture patterns around the femoral component, enhanced fixation is needed. In large zones of metaphyseal comminution, multiple fracture lines and those with severe varus or valgus deformity, dual fixation strategies are preferred. Whether it be nail-plate combination or dual plate combination techniques, for these more complex fracture patterns, dual fixation constructs allow for reliable, early weight-bearing and mobility but also provide more biomechanically stable fixation in the setting of severely osteoporotic bone, often occurring in a compromised host.
Dual plate constructs are ideal for those TKA components with a “closed box” where retrograde intramedullary nailing is not possible. Otherwise, nail-plate combination offers a reliable construct solution that maintains the neutral axis and allows for stress transfer across the distal femur for balanced stress and healing. Linking the construct is not required, and sequence is dealer’s choice. Whether you plate first or nail first, obtaining and maintaining length alignment and rotation is the goal and can be easily achieved. Often, the biomechanical enhancement is what is needed to “win the race” in treating complex periprosthetic fractures about TKA.
- References:
- Liporace FA, et al. J Orthop Trauma. 2019;doi:10.1097/BOT.0000000000001332.
- Liporace FA, et al. J Orthop Trauma. 2021;doi:10.1097/BOT.0000000000002235.
- Shah JK, et al. Injury. 2020;doi:10.1016/j.injury.2020.02.043.
Richard S. Yoon, MD, is a Healio | Orthopedics Today Editorial Board Member and clinical professor of orthopedic surgery at the Robert Wood Johnson Medical School at Rutgers University in New Brunswick, New Jersey.
Collapse
Read more about
Click Here to Manage Email Alerts