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van CCT (UK)

van CCT (UK)

Flexibele staaf versus standaard staaf bij plaatsing van een totale knie prothese: effecten op passing en functionele uitkomst van de prothese

- candidate number21884
- NTR NumberNTR5125
- ISRCTNISRCTN no longer applicable
- Date ISRCTN created
- date ISRCTN requested
- Date Registered NTR30-mrt-2015
- Secondary IDs600 NL46940.048.14
- Public TitleFlexibele staaf versus standaard staaf bij plaatsing van een totale knie prothese: effecten op passing en functionele uitkomst van de prothese
- Scientific TitleFlexible versus standard intramedullary rod in Triathlon primary total knee replacement: effects on sagittal contour of the distal femur, implant positioning, functional outcome and sizing
- hypothesisWe expect that the use of the flexible IM rod results in a post-operative sagittal contour of the distal femur that resembles the pre-operative situation, i.e. a better fit of the prosthesis, when compared to the use of the the standard IM rod
- Healt Condition(s) or Problem(s) studiedArthrosis, Joint, Wear
- Inclusion criteria• Patient with non-inflammatory knee osteoarthritis which is radiologically confirmed and which requires total knee replacement
• Age between 40 and 75 years, inclusive
• Patient plans to be available for follow-up until two years post-operative
• Patient is in stable health and is free of or treated for cardiac, pulmonary, haematological, or other conditions that would pose excessive operative risk
- Exclusion criteria• Patient has a BMI > 35
• Patient's expected physical activity after surgery is 2 or less on the UCLA Activity Scale
• Patient has had previous hip or knee replacement surgery in the last 6 months, or is planned to have a (second) hip or knee replacement in the next 6-12 months (because of the effect on function)
• Patient has had a previous hip replacement on the affected side (this may cause for a restriction for the rod placement during surgery)
• Patient has had major, non-arthroscopic surgery to the study knee, including HTO.
• Patient has an active, local infection or systemic infection
• Patient has physical, emotional or neurological conditions that would compromise compliance with post-operative rehabilitation and follow-up
• Bone stock compromised by disease, infection or prior implantation which cannot provide adequate support and/or fixation to the prosthesis
• Severe instability of the knee joint secondary to the absence of collateral ligament integrity and function
• Severe instability of the knee joint due to loss of cartilage reported as “substance loss”
• Patient has knee flexion < 90 degrees
• Patient has fixed flexion deformity >10 degrees (passive extension lag)
• Patient has > 30 degrees extension deficit (active restraint to extension)
• Patient does not have a proper functioning patella tendon on the affected side; measured as inability of active extension of the knee
• Patient has quadriceps weakness on the affected side; score on MRC scale < 4
• Patient has rheumatoid arthritis, any auto-immune disorder or immunosuppressive disorder
- mec approval receivedyes
- multicenter trialno
- randomisedyes
- masking/blindingSingle
- controlActive
- groupParallel
- Type2 or more arms, randomized
- Studytypeintervention
- planned startdate 1-mei-2015
- planned closingdate31-dec-2017
- Target number of participants60
- InterventionsThe intramedullary rod is used in TKA to position the femoral component in the correct orientation. The difference between two IM rods is that the flexible IM rod allows for bowing, and thus following the natural anatomy of the femur. There are no extra risks involved with use of the flexible IM rod.
- Primary outcomeThe contour of the distal femur is quantified in (first): the flexion angle of the TKA in the sagittal plane.
- Secondary outcome1. The contour of the distal femur is also quantified in the sagittal profile: anterior and posterior.

2. Functional outcome measured with:
o Get up and Go test
o Stair climbing test
o Knee power output
- TimepointsThe patients included in the study will be seen at several moments: pre-operative, operation/direct post-operative, and 3 months, 1 year and 2 years post-operative.
- Trial web siteN/A
- statusplanned
- Sponsor/Initiator Sint Maartenskliniek Nijmegen
- Funding
(Source(s) of Monetary or Material Support)
Stryker Nederland
- PublicationsN/A
- Brief summaryTotal knee arthroplasty (TKA) is a cost-effective surgical procedure for degenerative knee disease. TKA has good long-term results (Gill OS 1999). However, these results are not always related to patient satisfaction and functional outcome (Anderson JG 1996). This may be caused by the fact that the dynamics of the TKA do not properly mimic the dynamics of the natural knee. Manufacturers of TKA's have addressed this by integrating aspects of natural knee dynamics into their models.
The Triathlon primary TKA is a single-radius of curvature implant, mimicking a single flexion/extension axis located in the distal femur. It is hypothesised that the single-radius concept yields better function, and that it results in enhanced efficiency of the extensor muscles. A recent 4-year follow-up study of the Triathlon TKA shows good results for pain and functional outcome (Hamilton DF 2013). Three models of the Triathlon are currently available: the Posterior Stabilized (PS), Cruciate Retaining (CR) and Cruciate Substituting (CS) knee replacement. All these models can be placed by either using the standard intramedullary (IM) rod or the newer flexible intramedullary rod.
Up till now, the literature has not been conclusive whether the orthopaedic surgeon should use one of both options and acknowledges the dilemma of implanting the femoral component either according to the anatomy of the distal femur, or according to the longitudinal axis of the femur in the sagittal plane, thus ignoring the sagittal bowing (Yehyawi TM 2007). The first option (following distal anatomy) should result into a more flexed femoral component compared to a more extended femoral component. While the standard IM rod is still being considered a safe option, it is hypothesized that the advantage of the flexible rod is that, due to following the distal anatomy, less bone needs to be removed and that the femoral component has a proper fit to the natural anatomy of the distal femur in the sagittal plane. Together with the single radius concept of the Triathlon, this would lead to more natural femorotibial kinematics and, eventually, to better functional outcome.
The goal of this study is to compare the flexible IM rod to the standard IM rod in Triathlon primary TKA in terms of fit of the TKA and functional outcome. This comparison will help in the search for the optimal surgical technique in combination with a knee implant that mimics natural joint motion and feels best for the patient.
- Main changes (audit trail)
- RECORD30-mrt-2015 - 26-apr-2015

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