Knee implant study halted early: what we know
NCT ID NCT00734110
First seen Jun 24, 2026 · Last updated Jun 27, 2026 · Updated 1 time
Summary
This study looked at how well the P.F.C. Sigma knee replacement implant works in people with severe knee arthritis. Researchers planned to follow 723 patients for at least 5 years after surgery, tracking pain, function, and any complications. However, the study was terminated early, so the full long-term data is not available.
What this could mean
Our plain-language read of the trial. This is informational only, not medical advice or a prediction.
- Active substance
- P.F.C. Sigma Total Knee System (a knee replacement implant)
- What this could lead to
- If successful, this could confirm that the P.F.C. Sigma knee implant provides lasting pain relief and improved function for people with severe knee arthritis.
- What could go wrong
- The study was terminated early, so results may be incomplete. As a device study, individual outcomes vary and risks include implant failure, infection, or need for revision surgery.
This is an AI summary of the original study and may miss details. Read our disclaimer.
Study facts
What this study's own registry entry says, in plain language.
- Phase
-
Phase 4
Runs after approval, following long-term safety and how well the treatment works in everyday use.
- Participants
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723 people
The number who actually took part.
- Started
-
Jul 2000
- Finished
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Jun 2010
- Lead sponsor
-
A company
The lead sponsor is a pharmaceutical, biotech, or medical-device company.
Who can take part
This study's own entry requirements. Only the study team can say for certain whether you qualify.
- Ages
-
Children (under 18), adults (18 to 64) and older adults (65 and over)
- Sex
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Anyone
- Healthy volunteers
-
Not accepted
This study is not open to healthy volunteers. The entry requirements below say who it is open to.
Show the full entry requirements Hide the full entry requirements
Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.
Inclusion Criteria: * Patients who have given voluntary written informed consent to participate in this study. * Patients for whom primary Total Knee Replacement is indicated due to degenerative joint disease, including rheumatoid arthritis, osteoarthritis, avascular necrosis, and post-traumatic arthritis, which is causing pain, deformity, or limitation of function uncontrolled by medical treatment. * Patients who, in the opinion of the Investigator, are able to understand this study, co-operate with the investigational procedures and are willing to return to the hospital for all the scheduled post-operative follow-ups. * Male or female patients who are skeletally mature and for whom an appropriate size of device is available. Exclusion Criteria: * Patients scheduled for Revision Total Knee Arthroplasty, or who have had previous surgery to their knee except menisectomy, arthroscopy or synovectomy. * Patients experiencing any condition that may, in the opinion of the Investigator, interfere with the Total Knee Replacement's survival or outcome (e.g. Paget's disease, Charcot's disease, severe osteoporosis, etc.) * Patients who have evidence of active infections which may spread to other areas of the body (e.g. osteomyelitis, pyrogenic infection of the knee joint, overt infection, etc.). * Patients who are currently participating in any other clinical investigation of a device or pharmaceutical. * Patients having non-contained defects in the tibia or femur necessitating bone graft. * Patients with psychosocial disorders that would limit rehabilitation or follow-up. * Subjects with a known history of poor compliance to medical treatment. * Subjects who are known drug or alcohol abusers. * Other contraindications for the use of the P.F.C. ® S Knee System as listed in the package insert.
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Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
-
Princess Alexandra Hospital NHS Trust
Harlow, Essex, CM20 1QX, United Kingdom
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Other studies related to the condition(s) this trial covers.
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