Osteoarthritis, KneePFA/TKRNCT01326156
Study of Knee Replacements for Patellofemoral Osteoarthritis
A study testing Knee arthroplasty in people with Osteoarthritis, Knee and Patellofemoral Knee Arthroplasty, run by University of Aarhus at 1 site in Denmark.
Trial summary
This is a randomized comparison of PFA and TKR in treatment of isolated patellofemoral osteoarthritis. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Osteoarthritis, Knee, Patellofemoral Knee Arthroplasty
- What is being tested?
- Knee arthroplasty
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 100 participants
- Where
- 1 siteDenmark
- Study dates
- Jun 2007to Oct 2040
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Isolated PF-OA
Who cannot join
- Medial or lateral OA
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Patellofemoral Arthroplasty (PFA) Versus Total Knee Replacement (TKR) for Isolated Patellofemoral Osteoarthritis
This is a randomized comparison of PFA and TKR in treatment of isolated patellofemoral osteoarthritis.
Read the detailed description
Isolated patellofemoral osteoarthritis can be a disabling condition of the knee necessitating knee arthroplasty. It is debated whether total knee replacement or isolated patellofemoral replacement is the better treatment option. This randomized trial attempts to give a qualified answer to the debate by comparing clinical outcome (range of movement, stability, effusion, patellofemoral tracking, tenderness, stair climbing), patient self assessment scores (EQ-5D, Oxford Knee Score, KOOS, SF-36, AKS), complications (infections, revisions), longevity (survival analysis) and cost (direct and indirect) for the two implant types.
The Avon patellofemoral implant has been chosen, as this is the patellofemoral implant with the best documentation. The PFC Sigma CR total knee implant has been chosen as it a current standard implant and market leader.
- Being tested
- Knee arthroplasty
- Keywords
- Osteoarthritis, Knee, Knee cap, Patella, Patellofemoral
- Medical subject headings
- Osteoarthritis, Knee, Osteoarthritis, Patella Fracture
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Knee arthroplastyDevice
Also called PFA: Avon Patellofemoal arthroplasty (Stryker), TKR: PFC Sigma CR arthroplasty (DePuy)
Comparison of patellofemoral arthroplasty versus conventional total knee arthroplasty in cases of isolated patellofemoral osteoarthritis.
| Study group | Role | What they receive |
|---|---|---|
| Avon patellofemoral replacement | Experimental | Knee arthroplasty with insertion of patellofemoral joint replacement. Receives: Device: Knee arthroplasty |
| PFC Sigma CR total knee replacement | Active comparator | Knee arthroplasty with total (tricompartmental) knee replacement. Receives: Device: Knee arthroplasty |
What is being measured
The primary outcome is the main question the study is designed to answer.
Patient-reported outcomes (disease-specific and generic QoL instruments)
The physical functioning score of the Short Form (36) Health Survey is the primary outcome measure of the study. Disease-specific patient-reported outcomes (Oxford Knee Score, KOOS and Kujala) and a second generic quality of life measure (EQ5D).
Measured: 10 years
Secondary outcomes (1)
Implant survival, clinician assessment and cost.
Secondary outcome measures relate to implant survival, clinician assessment and cost. Implant survival will be assessed by 5- and 10-year implant survival rates and by analyzing causes for revision surgery. Clinician assessment includes Knee Society Score (stability, range of movement, effusion, tenderness etc.). Assessments of immediate and long-term costs are based on patient diaries, sick leave, use of medical services and drug prescriptions.
Measured: 10 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Mar 2011 (estimated)
- Study startJun 2007
- Primary completionApr 2025
- Study completionOct 2040 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (5)Papers the sponsor has linked to this study.
- Other trials for Osteoarthritis, KneeStudies of the same condition, open and under way.
- More trials run by University of AarhusThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Pragmatic, multi-centre, 1:1 parallel-group, randomised controlled trial. Double-blinded for 1st year. PROMs completion without staff involvement. Statistical consultants blinded.
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 100 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Aarhus
- Sponsor type
- University, hospital or other
- Collaborators
- Stryker Nordic, DePuy Orthopaedics, Copenhagen University Hospital, Rigshospitalet
- Responsible party
- Sponsor
- Investigators
- Anders Odgaard, FRCS, DMSc, Principal investigator, Dept. of Orthopaedics, Aarhus University Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01326156
- Sponsor's protocol ID
- 56789
- Acronym
- PFA/TKR
- Status last verified
- Nov 2020
- First submitted
- 19 May 2009
- Last updated
- 8 Jan 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: IPD that underlie the results reported in published article, after deidentification (text, tables, figures and appendices).
Publications
Martinique VB, Julie H, Snorre S, Soeren R, Kristensen WP, Zahid A, Alex L, Justin C, Anders O. Equivocal physical activity outcomes 10 Years after patellofemoral vs total knee replacement: Follow-up of a previously reported randomized controlled trial in isolated patellofemoral joint osteoarthritis. J ISAKOS. 2026 Apr;17:101037. doi: 10.1016/j.jisako.2025.101037. Epub 2025 Nov 15.
PubMed 41248881Odgaard A, Kappel A, Madsen F, Kristensen PW, Stephensen S, Attarzadeh AP. Erratum to: Patellofemoral Arthroplasty Results in Better Time-weighted Patient-reported Outcomes After 6 Years than TKA: A Randomized Controlled Trial. Clin Orthop Relat Res. 2023 Jul 1;481(7):1455-1457. doi: 10.1097/CORR.0000000000002713. Epub 2023 Jun 15. No abstract available.
PubMed 37352486Odgaard A, Kappel A, Madsen F, Kristensen PW, Stephensen S, Attarzadeh AP. Patellofemoral Arthroplasty Results in Better Time-weighted Patient-reported Outcomes After 6 Years than TKA: A Randomized Controlled Trial. Clin Orthop Relat Res. 2022 Sep 1;480(9):1707-1718. doi: 10.1097/CORR.0000000000002178. Epub 2022 Mar 21.
PubMed 35315804Fredborg C, Odgaard A, Sorensen J. Patellofemoral arthroplasty is cheaper and more effective in the short term than total knee arthroplasty for isolated patellofemoral osteoarthritis: cost-effectiveness analysis based on a randomized trial. Bone Joint J. 2020 Apr;102-B(4):449-457. doi: 10.1302/0301-620X.102B4.BJJ-2018-1580.R3.
PubMed 32228074Odgaard A, Madsen F, Kristensen PW, Kappel A, Fabrin J. The Mark Coventry Award: Patellofemoral Arthroplasty Results in Better Range of Movement and Early Patient-reported Outcomes Than TKA. Clin Orthop Relat Res. 2018 Jan;476(1):87-100. doi: 10.1007/s11999.0000000000000017.
PubMed 29529622
Study at a glance
From the registry record, last updated by the sponsor on 8 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Patellofemoral Arthroplasty (PFA) Versus Total Knee Replacement (TKR) for Isolated Patellofemoral Osteoarthritis
- ClinicalTrials.gov ID
- NCT01326156
- Acronym / sponsor ID
- PFA/TKR / 56789
- Keywords
- Osteoarthritis, Knee, Knee cap, Patella, Patellofemoral
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 100 participants (actual)
- Lead sponsor
- University of AarhusUniversity, hospital or other
- Collaborators
- Stryker Nordic, DePuy Orthopaedics, Copenhagen University Hospital, Rigshospitalet
- Study start
- Jun 2007 (actual)
- Primary completion
- Apr 2025 (actual)
- Study completion
- Oct 2040 (estimated)
- First posted
- 30 Mar 2011 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a randomized comparison of PFA and TKR in treatment of isolated patellofemoral osteoarthritis.
Detailed description
Isolated patellofemoral osteoarthritis can be a disabling condition of the knee necessitating knee arthroplasty. It is debated whether total knee replacement or isolated patellofemoral replacement is the better treatment option. This randomized trial attempts to give a qualified answer to the debate by comparing clinical outcome (range of movement, stability, effusion, patellofemoral tracking, tenderness, stair climbing), patient self assessment scores (EQ-5D, Oxford Knee Score, KOOS, SF-36, AKS), complications (infections, revisions), longevity (survival analysis) and cost (direct and indirect) for the two implant types.
The Avon patellofemoral implant has been chosen, as this is the patellofemoral implant with the best documentation. The PFC Sigma CR total knee implant has been chosen as it a current standard implant and market leader.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- Pragmatic, multi-centre, 1:1 parallel-group, randomised controlled trial. Double-blinded for 1st year. PROMs completion without staff involvement. Statistical consultants blinded.
| Arm | Type | Receives |
|---|---|---|
| Avon patellofemoral replacement | Experimental | Device: Knee arthroplastyKnee arthroplasty with insertion of patellofemoral joint replacement. |
| PFC Sigma CR total knee replacement | Active comparator | Device: Knee arthroplastyKnee arthroplasty with total (tricompartmental) knee replacement. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (1 listed)
- Isolated PF-OA
Key exclusion criteria (1 listed)
- Medial or lateral OA
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Knee arthroplastyAlso: PFA: Avon Patellofemoal arthroplasty (Stryker), TKR: PFC Sigma CR arthroplasty (DePuy)Comparison of patellofemoral arthroplasty versus conventional total knee arthroplasty in cases of isolated patellofemoral osteoarthritis. | Device | Avon patellofemoral replacement, PFC Sigma CR total knee replacement |
Primary outcome
Patient-reported outcomes (disease-specific and generic QoL instruments)
Time frame: 10 years
The physical functioning score of the Short Form (36) Health Survey is the primary outcome measure of the study. Disease-specific patient-reported outcomes (Oxford Knee Score, KOOS and Kujala) and a second generic quality of life measure (EQ5D).
1 secondary outcome
Implant survival, clinician assessment and cost.
Time frame: 10 years
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Jan 2026.
- Results publication: PubMed 41248881Martinique VB, Julie H, Snorre S, Soeren R, Kristensen WP, Zahid A, Alex L, Justin C, Anders O. Equivocal physical activity outcomes 10 Years after patellofemoral vs total knee replacement: Follow-up of a previously reported randomized controlled trial in isolated patellofemoral joint osteoarthritis. J ISAKOS. 2026 Apr;17:101037. doi: 10.1016/j.jisako.2025.101037. Epub 2025 Nov 15.
- Results publication: PubMed 37352486Odgaard A, Kappel A, Madsen F, Kristensen PW, Stephensen S, Attarzadeh AP. Erratum to: Patellofemoral Arthroplasty Results in Better Time-weighted Patient-reported Outcomes After 6 Years than TKA: A Randomized Controlled Trial. Clin Orthop Relat Res. 2023 Jul 1;481(7):1455-1457. doi: 10.1097/CORR.0000000000002713. Epub 2023 Jun 15. No abstract available.
- Results publication: PubMed 35315804Odgaard A, Kappel A, Madsen F, Kristensen PW, Stephensen S, Attarzadeh AP. Patellofemoral Arthroplasty Results in Better Time-weighted Patient-reported Outcomes After 6 Years than TKA: A Randomized Controlled Trial. Clin Orthop Relat Res. 2022 Sep 1;480(9):1707-1718. doi: 10.1097/CORR.0000000000002178. Epub 2022 Mar 21.
- Results publication: PubMed 32228074Fredborg C, Odgaard A, Sorensen J. Patellofemoral arthroplasty is cheaper and more effective in the short term than total knee arthroplasty for isolated patellofemoral osteoarthritis: cost-effectiveness analysis based on a randomized trial. Bone Joint J. 2020 Apr;102-B(4):449-457. doi: 10.1302/0301-620X.102B4.BJJ-2018-1580.R3.
- Results publication: PubMed 29529622Odgaard A, Madsen F, Kristensen PW, Kappel A, Fabrin J. The Mark Coventry Award: Patellofemoral Arthroplasty Results in Better Range of Movement and Early Patient-reported Outcomes Than TKA. Clin Orthop Relat Res. 2018 Jan;476(1):87-100. doi: 10.1007/s11999.0000000000000017.
- Individual participant dataSharing planned: Yes. IPD that underlie the results reported in published article, after deidentification (text, tables, figures and appendices).
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Anders Odgaard, FRCS, DMSc principal investigator
Dept. of Orthopaedics, Aarhus University Hospital
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Knee arthroplasty in people with Osteoarthritis, Knee and Patellofemoral Knee Arthroplasty, run by University of Aarhus at 1 site in Denmark.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 8 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Denmark. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Patient-reported outcomes (disease-specific and generic QoL instruments) (time frame: 10 years). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT01326156, which also lists 5 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Jan 2026.