Comparing knee joint replacement to surgical fixation for elderly patients with distal femur fractures
Official title: pDIFFIR: Geriatric Periprosthetic DIstal Femur: FIxation Versus Replacement - A Randomized Controlled Trial of Acute Open Reduction Internal Fixation (ORIF) Versus Distal Femur Replacement (DFR)
Run by Unity Health Toronto · NCT05805774 · Data updated 2026-11-12
This study is testing whether total knee joint replacement or surgical fixation works better for older patients with broken thigh bones near their knee to help them feel less pain and improve their daily activities.
Quick facts
| Study type | Interventional |
|---|---|
| Ages | 65 Years and up |
| Sex | All |
| Enrollment | 148 (estimated) |
| Sponsor | Unity Health Toronto Academic / other |
| Locations | 1 site (Toronto, Ontario) |
| Status | Recruiting |
| Started | October 17, 2025 |
| Main results expected | December 10, 2030 |
| Study ends | December 10, 2032 |
| Registry record updated | December 18, 2025 |
| Trial ID | NCT05805774 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Ideal candidates are individuals aged 65 and older with isolated acute periprosthetic fractures around a stable knee prosthesis.
✕Probably not a fit
Patients with active infections, open fractures, or significant neurovascular injuries may not benefit from this study.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
This clinical trial investigates two treatment options for elderly patients suffering from periprosthetic distal femur fractures: surgical fixation using plates or nails versus total knee joint replacement. The primary goal is to assess whether knee replacement leads to better pain relief and functional outcomes compared to fixation. Secondary objectives include evaluating mortality rates, reoperation needs, complications, post-operative pain, and overall quality of life. A total of 148 patients will be enrolled, with a focus on cost-effectiveness of both interventions.
Why it matters
Potential benefit: If successful, this study could provide clearer guidance on the most effective treatment for improving outcomes in elderly patients with distal femur fractures.
How similar studies have gone: Previous studies have shown varying success with similar surgical approaches, but this specific comparison of fixation versus replacement in this demographic is relatively novel.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: * • 65 years and older * Isolated periprosthetic fracture of the distal femur around a stable primary total knee arthroplasty (Lewis and Rorabeck Type 1-2) * Fracture is acute (within 1 week from time of injury) * Patient was ambulatory (with or without walking aids) in the community and at home prior to the injury * Independent or moderately frail with score of 3 to 6 on the validated Clinical Frailty Scale * Patient is able to read and understand the consent form document, or an interpreter is available to the patient at the time of consent and follow-up * Patient or substitute decision maker is able to provide written informed consent to participate in the study Exclusion Criteria: * • Active infection around the fracture (soft tissue or bone) * Open fracture * Bilateral femur fractures * Major neuro-vascular injury requiring intervention, compartment syndrome and major neurologic injuries * Pathological fracture excluding osteoporosis * Ipsilateral total knee arthroplasty using revision components (varus/valgus constraint, stemmed femoral components) * Periprosthetic distal femur fracture around a loose or failing primary total knee arthroplasty (Lewis and Rorabeck Type III) * Ipsilateral primary partial knee or patellofemoral arthroplasty * Previous ORIF of the distal femur or proximal tibia or patella * Current or previous extensor mechanism (patellar tendon, quadriceps tendon, or patella fracture) disruption or repair * Poly-trauma status (Injury Severity Score\>15) or any associated major injuries of the lower extremities that may hinder post-operative ambulation * Medical contraindication to surgery
Where it's running
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St. Michael's Hospital
Toronto, Ontario, Canada Recruiting
Study contacts
- Principal investigator: Amir Khoshbin, MD — Unity Health Toronto - St Michael's Hospital
- Study coordinator: Cassandra Tardif-Theriault
- Email: cassandra.tardif-theriault@unityhealth.to
- Phone: 416-864-6060
Similar studies
Other studies for the same condition or treatment. Recruiting studies are listed first.
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Carbon‑fiber lateral plate versus plate-and-nail repair for distal femur fractures
This trial will see if a carbon-fiber (CarboFix) lateral femur plate leads to fewer non-unions than the standard plate-plus-nail repair in adults having surgery for a distal femur fracture.
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Weight-Bearing CT for Healing of Periprosthetic Knee Fractures
This study tests weight-bearing CT scans to better assess healing after distal femur fractures around a knee implant in adults 50–90 years old who recently had revision knee surgery.
-
Comparing two surgical methods for treating distal femur fractures
This study is testing which of two surgical methods works better for helping older patients recover from specific knee fractures after they've had knee replacement surgery.
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Comparing knee replacement to surgical fixation for elderly patients with distal femur fractures
This study is trying to see if knee replacement or surgical fixation works better for older patients with certain types of thigh bone fractures.
How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.