Rising Incidence of Distal Femur Fractures in Older Patients Is Associated with Increased Costs of Care

At the AAOS 2024 Annual Meeting, Justin Haller, MD, orthopaedic traumatologist at University of Utah Health, and colleagues presented an ePoster revealing a significant increase in the incidence of distal femur fractures over the past decade, particularly in patients aged 60 years or more. Using U.S. databases, the researchers found the incidence rate to be three to five times higher than previous reports in the literature. AAOS Now Editorial Board member Stuart A. Green, MD, FAAOS, sat down with Dr. Haller to discuss the potential causes of this rise in cases, treatment trends, and the impact on the healthcare system.

Dr. Green: What motivated you to do this study?
Dr. Haller: When you look at distal femur fractures, the incidence rates in the literature seem to be lower than what most of us experience in practice. Most of those epidemiologic studies are done overseas or not using a database. We thought it’d be interesting to look at what the actual incidence was in the United States, and to look at trends in fixation over the years.

What was your approach?
We used two databases in the United States. One is the National Inpatient Sample, where we looked at trends in epidemiologic data. We also used the Medicare claims data to identify fixation trends, to see how that’s changed relative to intramedullary nailing, plating, and arthroplasty, and to look at cost.

What kind of data did you come up with?
[Our study found that] the rate is 27 [cases] per 100,000 [people], which is three to five times greater than what had previously been reported. And this increase [represents] doubling over the last decade, predominantly in patients greater than 60 years of age.

Is that just because the whole population is aging, or because the patients are unhealthier, or because they’re more active?
It is all those things. Also, [our data found an] increase in number of arthro-plasties that are being [performed relative to internal fixation]—primary arthroplasty, knee replacement, a hip, a revision hip replacement [with] a long stem.

So a lot of them are actually over the top-of-knee prosthesis?
That’s where a lot of them are. It’s kind of 50/50, between periprosthetic and native distal femur fractures.

What are some new conclusions about the technique to manage these?
Over the last decade, the number of arthroplasties for distal femur fractures [has] increased by five-fold, and the number of plating procedures decreased relative to that. About a decade ago, [arthroplasties] were being done 2 to 3 percent of the time. Most recently, it’s up to 14 percent of patients getting a distal femur replacement. Despite the increase in distal femur replacements, we haven’t seen clinical benefit to doing that surgery for those patients. [Additionally,] the cost is increased two to three times with distal femur replacements.

Have you looked at a comparison between nails and plates?
We did not isolate those and compare. We did see that nails stay relatively the same in terms of the rate being done; it’s about 7 or 8 percent through the last decade, [while] plates have decreased in the frequency of use [as they have been replaced by prosthesis].

How has this information modified your practice or your outlook?
This research identifies that distal femur fractures are a fragility fracture. They are very common. They have the same complication profile that hip fractures do. Hopefully, surgeons can continue to better identify treatment options, increase early weight bearing, and increase patients’ return to regular activities.

How about concepts of pre-injury management?
That’s a great point: Identifying pre-injury patients to optimize would be great. I think it highlights that fragility fractures are increasing at a dramatic rate, and we have to do better to improve [patients’] physiology, so that they can avoid these injuries.

And you have a dollar amount associated with these injuries?
For the distal femur replacements, it’s roughly $50,000 for the first 90 days of care, and for the other procedures—nails and plates—it’s around $35,000 to $40,000. A $10,000 to $15,000 difference in the first 90 days of care. Extrapolate this; [it’s] quite a hit to the healthcare system.

Stuart A. Green, MD, FAAOS, is cofounder and past president of the Limb Lengthening and Reconstruction Society, past president of the Association of Bone and Joint Surgeons, and an attending surgeon at the Tibor Rubin Long Beach VA Medical Center. He is the son, first cousin, and father of AAOS Fellows. Dr. Green is a member of the AAOS Now Editorial Board.