Stiff Knee After Replacement: Test Hinged Revision with Low-Dose Radiation
Official title: Treatment of Acquired Idiopathic Stiffness in Revision Total Knee Arthroplasty With Hinged Knee Prosthesis With or Without Low Dose Irradiation: A Multicentre Prospective Randomized Controlled Trial
Run by Mount Sinai Hospital, Canada · NCT07767097 · Data updated 2026-11-12
This trial tests whether adding low-dose radiation to a hinged revision knee replacement helps people with arthrofibrosis after knee replacement move their knee better.
Quick facts
| Study type | Interventional |
|---|---|
| Ages | 18 Years and up |
| Sex | All |
| Enrollment | 36 (estimated) |
| Sponsor | Mount Sinai Hospital, Canada Academic / other |
| Locations | 4 sites (Los Angeles, California and 3 other locations) |
| Status | Recruiting |
| Started | April 1, 2026 |
| Main results expected | December 31, 2028 |
| Study ends | January 31, 2029 |
| Registry record updated | August 17, 2026 |
| Trial ID | NCT07767097 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Adults with AIS after primary TKA undergoing hinged revision TKA and with ROM less than 70 degrees or flexion contracture greater than 20 degrees without another identifiable cause.
✕Probably not a fit
Patients with stiffness due to non-AIS causes, or those who do not respond to irradiation, may not experience added benefit.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
This randomized-ish trial compares hinged revision total knee arthroplasty with and without low-dose external beam irradiation in adults with acquired idiopathic stiffness after primary knee replacement. The primary outcome is knee range of motion at one year, with secondary measures including functional scores, additional surgeries, and safety events. The approach targets excessive scar tissue by combining surgical intervention with a defined radiotherapy dose known to inhibit scar-forming cells. Eligible participants have a hinged revision knee for AIS and specific ROM limitations, while exclusions include non-AIS causes and irradiation contraindications. The study is led by Mount Sinai Hospital with international site collaboration at USC, University of Utah, and Humber River Hospital.
Why it matters
Potential benefit: If successful, patients may achieve greater knee motion and improved function after revision surgery.
How similar studies have gone: Evidence from retrospective data suggests improved ROM with LDI, but no prospective randomized trials have confirmed benefit.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: * Adults (≥18 years) undergoing revision TKA with a hinged prosthesis for AIS after primary TKA * Patient with a ROM arc \<70 degrees or flexion contracture of \>20 degrees without any identifiable cause for stiffness (e.g. component oversizing, malrotation, infection, or periprosthetic fracture). Exclusion Criteria: * Revision for causes other than AIS (e.g., component malposition, infection, periprosthetic fracture) * Prior ipsilateral knee infection * Revision to non-hinged prosthesis * Medical contraindications to surgery * Medical contraindications to irradiation * Currently pregnant or planning to become pregnant during the study period
Where it's running
-
Mount Sinai Hospital
Toronto, Ontario, Canada Recruiting -
University of Southern California
Los Angeles, California, United States Not yet recruiting -
University of Utah
Salt Lake City, Utah, United States Not yet recruiting -
Humber River Hospital
Toronto, Ontario, Canada Not yet recruiting
Study contacts
- Principal investigator: Jesse Wolfstadt, MD, MSc — Mount Sinai Hospital
- Study coordinator: Jesse Wolfstadt, MD, MSc
- Email: jesse.wolfstadt@sinaihealth.ca
- Phone: 416-586-4800
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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.