Recruiting

Fixation vs. ReplacementDIFFIR - Geriatric Distal Femur Fixation Versus Replacement

Sponsor:

Unity Health Toronto

Code:

NCT04076735

Conditions

Distal Femur Fracture

Eligibility Criteria

Sex: All

Age: 65+

Healthy Volunteers: Not accepted

Interventions

Distal femoral replacement

Surgical Fixation (ORIF)

Study Details

Brief summary:

The current standard of care for most intra-articular distal femur fractures (above the knee joint) in geriatric patients is a surgical fixation using plates and screws to hold the fracture pieces in the correct position, until the fracture as healed.

However, surgical fixation of these complex fractures in geriatric patients, is associated with significant complications, such as non-union (when the broken bone does not heal properly), infection and the need for revision surgery. Additionally, surgical fixation requires prolonged immobilization of of the affected limb (typically around 6-12 weeks post-operatively), which can lead to disability and other complications. Geriatric patients, especially those frail and with cognition impairment, are unable to adhere to the immobilization restrictions, which leads to an increased risk of fixation failure (broken bone does not heal).

Another treatment option for those patients is an acute distal femoral replacement (artificial knee), where damaged parts of the knee joint are replaced with artificial prosthesis. This procedure allows patients to walk immediately after the surgery and faster return to previous level of function, therefore avoiding the complications for immobilization.

There is a lack of guideline and evidence to suggest which surgical technique is best to provide superior function outcomes, lower complications and reduced costs. The proposed study seeks to answer this question by performing a large clinical trial comparing knee replacement versus surgical fixation in geriatric patients with distal femur fracture.

Conditions

Distal Femur Fracture

Study ID

NCT04076735

Start date

Oct 1, 2021

Status verified date

Apr, 2026

Completion date

Dec 31, 2028

Anticipated

Primary completion date

Dec 31, 2027

Anticipated

Eligibility Criteria

Sex: All

Age: 65+

Healthy Volunteers: Not accepted

Inclusion Criteria:

Male and female patients
65 years and older
Isolated fracture of the distal femur (Classification 33)
Fracture is amendable to both treatments
Fracture is acute (within 2 weeks from time of injury)
Patient was ambulatory (with or without walking aids) prior to the injury
Independent or moderately frail with score of 3 to 6 on the Clinical Frailty Scale
Patient is able to read and understand English, French, or Spanish
Patient or substitute decision maker is able to provide written informed consent to participate in the study

Exclusion Criteria:

Active or previous infection around the fracture (soft tissue or bone)
Open fracture
Bilateral femur fractures
Major vascular injuries requiring intervention, compartment syndrome and major neurologic injuries
Pathological fracture excluding osteoporosis
Previous surgical fixation or total knee replacement of the distal femur or proximal tibia
Previous surgical fixation or hemi/total replacement of the hip
Current or previous extensor mechanism (patellar tendon, quadriceps tendon, or patella fracture) disruption or repair
Polytrauma (Injury Severity Score > 15) or any associated major injuries of the lower extremities
Previous medical diagnosis of dementia
Medical or surgical contra-indication to surgery

Study Design

Enrollment

140 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Distal femoral replacement (DFR)

Distal femoral replacement will be performed by excising the distal portion of the femur (up to two thirds) and replacing with a prosthesis incorporating a hinged total knee replacement.

Surgical approach and implant selection will be at the discretion of the treating surgeon and within the standard of care. Surgeons performing this procedure will be qualified by training and experience in arthroplasty.

active comparator: Surgical Fixation (ORIF)

Surgical fixation of the distal femoral fracture will be performed with the goals of obtaining and maintaining anatomic reduction and stable fixation of the distal portion of the femur. Surgical approach and implant selection for the surgical fixation (ORIF) will be at the discretion of the treating surgeon and within the standard of care. Surgeons performing this procedure will be qualified by training and experience in trauma of the knee.

Interventions

Distal femoral replacement

The distal portion of the femur (up to two thirds) is excised and replaced by a endoprosthesis incorporating a hinged total knee replacement.

Surgical Fixation (ORIF)

A trained orthopaedic surgeon uses open or minimally invasive reduction techniques and achieves stable fixation with internal fixation devices (plates/screws or intramedullary nail) to restore structural integrity and alignment of the distal femur

Primary outcome measure

Oxford Knee Score (OKS) [ Time Frame: Our primary outcome is knee pain and function as measured by repeated measures of the Oxford Knee Score at 3, 6, 9 and 12 -months post-surgery to detect a 5 point improvement on the OKS with 0.5 correlation between assessments. ]

Central Contacts and Locations

Central contacts

Cassandra Tardif-Theriault, BKin

+1416-864-6060 cassandra.tardif-theriault@unityhealth.to

Locations

St Michael's Hospital - Unity Health Toronto

Recruiting

Toronto, Ontario, Canada

Contacts

Cassandra Tardif-Theriault, BKin

416-864-6060 cassandra.tardif-theriault@unityhealth.to

Principal Investigator:

Amir Khoshbin, MD

More Information

Sponsor

Unity Health Toronto

Last update posted

May 6, 2026

Last verified

Apr, 2026

Keywords

Distal Femur Fracture; Geriatric fracture

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Unity Health Toronto on 2026-05-06.