Replacement vs Fixation for Distal Femur Fractures

(pDIFFIR Trial)

Overseen By Cassandra Tardif-Theriault

Age: 65+

Sex: Any

Trial Phase: Academic

Sponsor: Unity Health Toronto

Disqualifiers: Active infection, Open fracture, Major neuro-vascular injury, Pathological fracture, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: Unknown

Duration: 12 months

148 Participants Needed

Trial Summary

What is the purpose of this trial?

Periprosthetic distal femur fractures are a significant source of morbidity and mortality for elderly patients. One treatment option involved a surgical fixation with plates or nails, screws and cables/wires along the side of your fractured bone. The second method consists in replacing your knee joint with an artificial knee prosthesis (artificial knee joint). The primary objective is to determine if acute distal femur replacement improves knee pain and functional outcomes compared to surgical fixation. Secondary outcomes are mortality, reoperation, complications, post-operative pain and quality of life. A health economic analysis will be conducted to assess the cost-effectiveness of both treatments. A total of 148 patients (74/group) will be enrolled in the study.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What data supports the effectiveness of the treatment for distal femur fractures?

Research comparing distal femoral replacement (DFR) and open reduction internal fixation (ORIF) for distal femur fractures suggests that both treatments are used, but there is limited data directly comparing their outcomes. Some studies focus on factors like implant survivorship and functional recovery, indicating that both methods have been effective in different scenarios. ^{1 2 3 4 5}

Is distal femur replacement or fixation generally safe for humans?

Research shows that both distal femur replacement and surgical fixation have been used safely in humans for treating fractures around the knee, with studies comparing their complication rates. While specific safety data for other conditions isn't detailed, these treatments are generally considered safe for managing fractures. ^{1 2 3 5 6}

How does the treatment for distal femur fractures differ from other treatments?

Distal femur replacement (DFR) is unique because it involves replacing the damaged part of the femur with an artificial joint, which can allow for earlier mobilization compared to open reduction and internal fixation (ORIF), where the bone is repaired using metal plates and screws. This approach may be particularly beneficial for older patients or those with complex fractures. ^{1 2 3 5 7}

Research Team

Jesse I Wolfstadt, MD

Principal Investigator

Mount Sinai Health Hospital

Amir Khoshbin, MD

Principal Investigator

Unity Health Toronto - St Michael's Hospital

Eligibility Criteria

This trial is for individuals aged 65 or older who have a specific type of knee fracture (periprosthetic distal femur fracture) around a stable knee replacement. Candidates must have been able to walk before the injury, even if they needed help, and not be severely frail. They should understand the consent form or have an interpreter available.

Inclusion Criteria

I can read and understand the consent form, or I have an interpreter who can help me.

I have a fracture near my knee replacement but the implant is stable.

I was able to walk on my own or with help before my injury.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo either surgical fixation or distal femur replacement

12 months

Follow-up

Participants are monitored for knee function, mortality, and other outcomes

24 months

Treatment Details

Interventions

• Distal Femur Replacement
• Surgical fixation

Trial Overview The pDIFFIR study compares two treatments for elderly patients with certain knee fractures: surgical fixation using hardware like plates or nails versus replacing the damaged bone with an artificial joint. The goal is to see which method better improves pain and function.

Participant Groups

Group I: Group A - DFR Active Control 1 Intervention

Group II: Group B - ORIF Active Control 1 Intervention

Distal Femur Replacement is already approved in European Union, United States, Canada for the following indications:

Approved in European Union as Distal Femoral Replacement for:

• Periprosthetic distal femur fractures
• Geriatric distal femur fractures

Approved in United States as Distal Femoral Replacement for:

• Periprosthetic distal femur fractures
• Geriatric distal femur fractures

Approved in Canada as Distal Femoral Replacement for:

• Periprosthetic distal femur fractures
• Geriatric distal femur fractures

Who Is Running the Clinical Trial?

Unity Health Toronto

Lead Sponsor

Trials

572

Recruited

470,000+

Mount Sinai Hospital, Canada

Collaborator

Trials

210

Recruited

70,700+

Findings from Research

In a study comparing distal femoral replacement (DFR) and open reduction and internal fixation (ORIF) for comminuted distal femur fractures, DFR showed a trend towards lower rates of revision and reoperation at 2 years (90% vs. 50% for ORIF), although this was not statistically significant.

Patients treated with DFR experienced significantly higher estimated blood loss (592 mL vs. 364 mL) and longer hospital stays (13 days vs. 6.5 days) compared to those treated with ORIF, indicating a trade-off between potential benefits and increased surgical risks.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Distal femoral replacement versus ORIF for severely comminuted distal femur fractures. Tibbo, ME., Parry, JA., Hevesi, M., et al.[2022]

In a study of 72 patients with displaced periprosthetic distal femur fractures, those treated with open reduction and internal fixation (ORIF) had better Knee Society Functional Scores compared to those treated with distal femoral replacement (DFR).

However, the ORIF group experienced a significantly higher total incidence of revision surgeries, indicating that while ORIF may offer better functional outcomes, it also carries a greater risk of needing additional operations.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Periprosthetic Fractures of the Distal Femur: Is Open Reduction and Internal Fixation or Distal Femoral Replacement Superior? Darrith, B., Bohl, DD., Karadsheh, MS., et al.[2021]

In a study of 58 patients with periprosthetic distal femur fractures, the type of surgical treatment (open reduction internal fixation or distal femoral replacement) did not significantly affect mortality, complications, or functional recovery after one year.

Age was a critical factor, as older patients (especially those over 85) were more likely to lose their ability to walk and require skilled nursing care, highlighting that age at injury is a stronger predictor of outcomes than the surgical method used.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Predictors of Functional Recovery Following Periprosthetic Distal Femur Fractures. Ruder, JA., Hart, GP., Kneisl, JS., et al.[2022]

In a study of 115 patients over 64 years old with periprosthetic distal femur fractures, both open reduction and internal fixation (ORIF) and distal femoral replacement (DFR) showed no significant differences in 1-year mortality, ambulatory status, reoperations, or hospital readmissions after treatment.

However, DFR was associated with longer hospital stays and a higher rate of blood transfusions compared to ORIF, indicating that while both treatments are equally effective in the short term, DFR may involve more immediate complications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Outcomes of Geriatric Periprosthetic Distal Femur Fractures: Comparison of Fixation Versus Reconstruction. Joseph, NM., Zuke, W., Sharpe, M., et al.[2023]

A systematic review of 32 studies involving 1,258 periprosthetic distal femur fractures found that open reduction and internal fixation (ORIF) and distal femoral replacement (DFR) have similar rates of surgical complications and reoperations, indicating both methods are comparably safe.

However, patients treated with DFR experienced significantly higher medical complication rates (23.1% for DFR vs. 8.5% for ORIF), suggesting that while DFR can be effective, it may carry additional health risks that need to be considered.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Distal Femoral Replacement versus Operative Fixation for Periprosthetic Distal Femur Fractures: A Systematic Review and Meta-Analysis. Bundschuh, KE., Grommersch, BM., Tipton, SC., et al.[2023]

A meta-analysis of 58 studies involving 1484 patients found no significant differences in complications or reoperation rates between primary distal femoral replacement (DFR) and open reduction and internal fixation (ORIF) for treating periprosthetic distal femur fractures.

However, patients treated with ORIF had a greater mean knee range of motion compared to those treated with DFR, suggesting that while both treatments are similarly safe, ORIF may offer better functional outcomes in terms of mobility.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Distal Femur Replacement Versus Open Reduction and Internal Fixation for Treatment of Periprosthetic Distal Femur Fractures: A Systematic Review and Meta-Analysis. Wadhwa, H., Salazar, BP., Goodnough, LH., et al.[2022]

In a study of 38 patients aged 70 and older with distal femur fractures, those who underwent distal femoral replacement (DFR) had better outcomes in terms of mobility, with all DFR patients being ambulatory at one year compared to 25% of those who had open reduction internal fixation (ORIF).

The ORIF group had a significant nonunion rate of 18% and an average time to fracture union of 24 weeks, highlighting potential challenges in recovery compared to DFR, although overall reoperation rates and other outcomes did not show statistically significant differences between the two groups.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Open Reduction vs Distal Femoral Replacement Arthroplasty for Comminuted Distal Femur Fractures in the Patients 70 Years and Older. Hart, GP., Kneisl, JS., Springer, BD., et al.[2018]

References

1. France pubmed.ncbi.nlm.nih.gov

Distal femoral replacement versus ORIF for severely comminuted distal femur fractures. [2022]

2. United States pubmed.ncbi.nlm.nih.gov

Periprosthetic Fractures of the Distal Femur: Is Open Reduction and Internal Fixation or Distal Femoral Replacement Superior? [2021]

3. United States pubmed.ncbi.nlm.nih.gov

Predictors of Functional Recovery Following Periprosthetic Distal Femur Fractures. [2022]

4. United States pubmed.ncbi.nlm.nih.gov

Outcomes of Geriatric Periprosthetic Distal Femur Fractures: Comparison of Fixation Versus Reconstruction. [2023]

5. United States pubmed.ncbi.nlm.nih.gov

Distal Femoral Replacement versus Operative Fixation for Periprosthetic Distal Femur Fractures: A Systematic Review and Meta-Analysis. [2023]

6. United States pubmed.ncbi.nlm.nih.gov

Distal Femur Replacement Versus Open Reduction and Internal Fixation for Treatment of Periprosthetic Distal Femur Fractures: A Systematic Review and Meta-Analysis. [2022]

7. United States pubmed.ncbi.nlm.nih.gov

Open Reduction vs Distal Femoral Replacement Arthroplasty for Comminuted Distal Femur Fractures in the Patients 70 Years and Older. [2018]