Overview

This trial is active, not recruiting.

Condition osteoarthritis, knee
Treatments oxford uni knee
Sponsor University of Aarhus
Collaborator Aarhus University Hospital
Start date May 2009
End date October 2017
Trial size 75 participants
Trial identifier NCT00679120, 20070258

Summary

The purpose of this scientific study is to clarify whether there is a relationship between the appearance of radiolucent lines in bone-cement interphase of the tibial component of the different models of the Oxford Uni Knee prosthesis and poor prognosis of these prostheses. This will be accomplished in a se-ries of three different Oxford Uni Knees.

United States No locations recruiting
Other Countries No locations recruiting

Study Design

Allocation randomized
Endpoint classification safety/efficacy study
Intervention model parallel assignment
Masking single blind (subject)
Primary purpose treatment
Arm
(Active Comparator)
Cemented single pegged femur with standard tibial bearing tray
oxford uni knee Biomet, Oxford Uni Knee, single pegged femur
Oxford Uni Knee inserted at the time of surgery
(Active Comparator)
Cemented twin pegged femur with standard tibial bearing tray
oxford uni knee Biomet, Oxford Uni Knee, twin pegged femur
Oxford Uni Knee inserted at the time of surgery
(Active Comparator)
Cementless tibial bearing tray and femur (porous coated and HA coated)
oxford uni knee Biomet, Oxford Uni Knee, cementless femur
Oxford Uni Knee inserted at the time of surgery (porous coated and HA coated)

Primary Outcomes

Measure
Three way randomized comparison of migration (prosthetic fixation) by Model Based RSA with three different Oxford Uni Knee prosthesis (both tibial trays and femoral components will be assessed)
time frame: 2016

Secondary Outcomes

Measure
Fluoroscopy (screening) roentgenograms for determination of RLL around the tibial component and "overhang" of the tibial trays.
time frame: 2016

Eligibility Criteria

Male or female participants at least 18 years old.

Inclusion Criteria: 1. Patients, both men and women, with anteromedial unicompartmental knee osteoarthritis 2. Patients found suitable for UKA with telos stress-radiographs 3. Patients with sufficient bone quality to allow insertion of a Uni Knee prosthesis 4. Patellofemoral osteoarthritis is not a contraindication if the patient does not have symptoms from the patellofemoral joint 5. Patients can only take part in one knee study 6. All age groups, in good condition and responsible adults 7. Informed, written compliance consent. Exclusion Criteria: 1. Patients with neuromuscular or vascular diseases in the affected leg 2. Patients found to be unsuitable for UKA before or at surgery 3. Preoperative extensions defect greater than 10 degrees 4. Preoperative maximal flection of less than 100 degrees 5. Symptomatic patellofemoral osteoarthritis 6. Insufficiency with regard to ACL 7. Patients templated to a size XS or XL femoral component prior to surgery. 8. Patients with osteoporosis on the basis of preoperative x-rays or earlier diagnosis 9. Continuous medical treatment with vitamin K antagonist (Warfarin), known to reduce bone mass in general by a factor of 5 10. Patients with fracture sequelae (intraarticular fracture and all tibial condyle fractures) 11. Patients previous having PTO or other extensive knee surgery 12. Patients with metabolic bone disease 13. Patients with rheumatoid arthritis 14. Postmenopausal female patients being treated with systemic hormonal substitution (not taking into local vaginal treatment) 15. Patients who intermittently or continuously require treatment with systemic glucocorticoids 16. Non-Danish citizens 17. Insufficient command of the Danish language (read and speak) 18. Senile dementia 19. Misuse of drugs or Alcohol 20. Serious psychiatric illness 21. Disseminated malignant disease (cancer) and treatment with radiation or chemotherapy 22. Serious systemic disease (e.g.. hemiparesis and severe Parkinsonism) 23. Systemic hip or back condition 24. Employed by the department of orthopaedic surgery 25. On-going case involving work injury of the knee 26. Patients with poor dental status

Additional Information

Official title Oxford Partial Knee Replacement: A Randomized Clinical Trial of Three Implant Types.
Principal investigator Kjeld Soballe, MD, Prof.
Description The purpose of this scientific study is to clarify whether there is a relationship between the appearance of radiolucent lines in bone-cement interphase of the tibial component of the different models of the Oxford Uni Knee prosthesis and poor prognosis of these prostheses. This will be accomplished in a series of three different Oxford Uni Knees by studying: 1. Three way randomized comparison of migration (prosthetic fixation) by Model Based RSA with three different Oxford Uni Knee prosthesis (both tibial trays and femoral components will be assessed). 2. Fluoroscopy (screening) roentgenograms for determination of RLL around the tibial component and "overhang" of the tibial trays. 3. Changes in periprosthetic bone mineral density between the three randomized groups evaluated in the proximal tibia and distal femur on the surgical side and on the unaffected tibial condyle area (BMD). 4. Clinical function of the Uni Knee evaluated by a score system using a recent Danish adaptation of the Oxford Knee Score that consists of a questionnaire filled-out by the patient with 12 simple questions on pre-and postoperative assessment of the ADL. 5. Analysis of wear of the mobile polyethylene (meniscus) including a methodical study as to whether the technique requires weightbearing (standing) stereoroentgenograms or whether non-weightbearing stereoroentgenograms can be used (assessed with Model Based RSA). 6. If a fast bone-remodeling increases the risk of aseptic loosening (histomorphometric results combined with RSA results and possible revision) 7. Increased risk of aseptic loosening with cemented (two designs) compared to uncemented im-plants. 8. If bone-remodeling of the proximal tibia is dependent on gender and age. The study would be considered a success if all designs of the prostheses are firmly fixed and remain so during the entire period of study, that is, no increasing migration is seen using RSA. It would be a success if the appearance of RLL beneath the implant in the proximal tibia is unrelated to bone loss and prosthesis migration. The hypotheses are: 1. RLL in relation to the tibial component is unimportant for fixation of the Oxford Uni Knee as assessed with DEXA and RSA. 2. There is very little wear of the polyethylene in the course of a 5 year follow-up as assessed with RSA. 3. The femoral component is expected to remain fixed throughout the entire period of follow-up. 4. Function assessment as ROM (range of motion) after UKA is satisfactory and generally better than after TKA. 5. All three prosthetic designs are expected to migrate minimally and remain fixed throughout the follow-up period, but the uncemented design is expected to be superior to the cemented design. 6. No difference in clinical outcome between the three prosthetic types. 7. The bone-remodeling rate in the medial periarticular tibia bone increases the risk of aseptic loosening. The primary parameters of effect are RLL, RSA and DEXA. The secondary parameters of effect are bone-remodeling, wear analysis, Oxford Knee Score (ADL) and ROM.
Trial information was received from ClinicalTrials.gov and was last updated in October 2014.
Information provided to ClinicalTrials.gov by University of Aarhus.