A Comparison of Fixation Method in Total Knee Arthroplasty - Low Viscosity Versus High Viscosity Bone Cement
Information source: University of Aarhus
Information obtained from ClinicalTrials.gov on March 24, 2008
Link to the current ClinicalTrials.gov record.
Condition(s) targeted: Osteoarthritis
Intervention: Osteopal G vs. Refobacin-Palacos R bone cement (Device)
Phase: N/A
Status: Not yet recruiting
Sponsored by: University of Aarhus Official(s) and/or principal investigator(s):
Kjeld Søballe, MD, Prof., Principal Investigator, Affiliation: Orthopaedic Center, Aarhus University Hospital, Tage-Hansens Gade 2, 8000 Aarhus C, Denmark.
Overall contact:
Maiken Møller-Pedersen, MD, Phone: 89 49 74 66, Ext: 45, Email: mm-p@dadlnet.dk
Summary
The purpose of this study is to compare the early migration and periprosthetic bone changes
of two total knee arthroplasties fixated with two different type bone cement.
Clinical Details
Official title: A Comparison of Fixation Method in Total Knee Arthroplasty - Low Viscosity Versus High Viscosity Bone Cement. A Prospective Randomized Migration- and Bone Density Study on Primary Cemented Knee Implants.
Study design: Treatment, Randomized, Double-Blind, Active Control, Parallel Assignment, Safety/Efficacy Study
Primary outcome: Tibial prosthesis part migration evaluated by RSA.Periprosthetic bone changes evaulated by DEXA.
Secondary outcome: Micromotion of the modular polyethylen liner in both type prostheses evaluated by RSA estimating the role of wear.
Detailed description:
Around 4% of total knee arthroplasties (TKA) are revised 15 years after the primary
operation, most due to loosening of the implant. About 70 % TKA are fixed with bone cement
and in general the results after total knee arthroplasty are excellent and with the existing
technique about 95% well functioning prostheses can be expected 10 years post surgery. The
most serious late complication to surgery is aseptic loosening of the implants; and this
remains one of the main courses of failure of both uncemented and cemented total knee
implants.
Implant design, method of fixation, the quality of bone cement, surgerytechnique and the bone
mass density are some of the factors that have a large influence on implant stability.
Fixation of the tibia baseplates in total knee arthroplasty can be obtained by different type
bone cement.
In this project we are using a modular tibia component with a central wedge-shaped stem. Upon
randomization at surgery the implant is consolidated in the bone with either low-viscosity or
high-viscosity bone cement.
The purpose of this study is to compare the early migration of a total knee implant fixated
with two different bone cements using RSA (radio stereophotogrammetric analysis) for
evaluation. Furthermore, we will make research into the periprosthetic bone and its changes
post surgery using DEXA. Finally, the extend of the expected micromovements between the
polyethylen liner and the metal backing of the titanium plateau will be compared and taken
into account with the results.
Several factors can influence the long-term survival of cemented TKA. Bone-sclerosing at the
tibia condyles may induce a problem with cement penetration into the cancellous bone.
Furthermore, blood-contamination in the cancellous bone may reduce the shear-strength at the
bone-cement site by 50%. A solid cement-implant interface limits the amount of debris in the
interface bringing down the risk of radiolucent lines and osteolysis. The tibial implant used
in this study is designed with a rim under the plateau to support the cement layer on the
tibial condyles at the time of fixation. The implant has a stem making it more resistant to
shearing forces. In this study we primarily consider the bone cement viscosity on the
outcome. Both types are used in hip-arthroplasties with good results.
To evaluate both the implant-bone micromotions and the polyethylen-implant micromovements
metal markers have been placed on the tibial implants pre-operatively. They will also be
inserted into the tibial bone and into the tibial polyethylen intra-operatively allowing us
to evaluate stereo x-rays by a photogrammetric computer analyses called RSA at the
Orthopaedic Center, Aarhus University Hospital. Follow-up stereo x-rays will be scheduled for
1 week, 3 months, 6 month, 1 years and 2 years post-surgery. Periprostetic bone density will
be evaluated at 1 week, 1 year and 2 years upon inclusion at the Orthopaedic Center, Aarhus
University Hospital.
Eligibility
Minimum age: 70 Years.
Maximum age: N/A.
Gender(s): Both.
Criteria:
Inclusion Criteria:
- Patients with one- or double-sided primary knee arthrosis.
- Patients with a sufficient bone quality for implantation of knee prosthesis.
- Informed and written patient consent.
Exclusion Criteria:
- Patients with neuromuscular or vascular diseases in the affected leg.
- Patients who peroperatively are estimated unsuitable for knee arthroplasty e. g. due to
bone cysts or dilution of the bone mass.
- Patients who use non-steroid anti-inflammatory drugs (NSAID) and cannot refrain from
taking them postoperatively (this includes COX-2-inhibitors).
- Patients with osteoporosis estimated from the preoperative x-ray or former diagnosis
of osteoporo-sis.
- Patients with knee arthrosis following fracture sequelae.
- Women, who are pregnant or are at risk of getting pregnant throughout the 2 year
follow-up.
Locations and Contacts
Maiken Møller-Pedersen, MD, Phone: 89 49 74 66, Ext: 45, Email: mm-p@dadlnet.dk
Orthopaedic Center, Aarhus University Hospital, Aarhus 8000, Denmark; Not yet recruiting
Maiken Møller-Pedersen, MD, Phone: 89 49 74 66, Ext: 45, Email: mm-p@dadlnet.dk
Kjeld Søballe, MD, Prof., Phone: 89497425, Ext: 45, Email: ovl09ks@as.aaa.dk
Maiken Møller-Pedersen, MD, Sub-Investigator
Ole Rahbek, MD, Ph.D., Sub-Investigator
Frank Madsen, MD, Sub-Investigator
Kjeld Søballe, MD, Prof., Principal Investigator
Additional Information
Starting date: April 2007
Ending date: June 2010
Last updated: April 18, 2007
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