Oxford Partial Knee Replacement. A Randomized Clinical Trial of Three Implant Types

This study is currently recruiting participants. (see Contacts and Locations)
Verified March 2012 by University of Aarhus
Sponsor:
Collaborators:
Aarhus University Hospital
Vejle Hospital
Biomet, Inc.
Information provided by (Responsible Party):
University of Aarhus
ClinicalTrials.gov Identifier:
NCT00679120
First received: May 14, 2008
Last updated: March 20, 2012
Last verified: March 2012
  Purpose

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.


Condition Intervention
Osteoarthritis, Knee
Device: Oxford Uni Knee

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind (Subject)
Primary Purpose: Treatment
Official Title: Oxford Partial Knee Replacement: A Randomized Clinical Trial of Three Implant Types.

Resource links provided by NLM:


Further study details as provided by University of Aarhus:

Primary Outcome Measures:
  • 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 ] [ Designated as safety issue: Yes ]

Secondary Outcome Measures:
  • Fluoroscopy (screening) roentgenograms for determination of RLL around the tibial component and "overhang" of the tibial trays. [ Time Frame: 2016 ] [ Designated as safety issue: Yes ]

Estimated Enrollment: 75
Study Start Date: May 2009
Estimated Study Completion Date: October 2017
Estimated Primary Completion Date: October 2017 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: 1
Cemented single pegged femur with standard tibial bearing tray
Device: Oxford Uni Knee
Oxford Uni Knee inserted at the time of surgery
Other Names:
  • Biomet, Oxford Uni Knee, single pegged femur
  • Biomet, Oxford Uni Knee,standard tibial bearing tray
Active Comparator: 2
Cemented twin pegged femur with standard tibial bearing tray
Device: Oxford Uni Knee
Oxford Uni Knee inserted at the time of surgery
Other Names:
  • Biomet, Oxford Uni Knee, twin pegged femur
  • Biomet, Oxford Uni Knee, standard tibial bearing tray
Active Comparator: 3
Cementless tibial bearing tray and femur (porous coated and HA coated)
Device: Oxford Uni Knee
Oxford Uni Knee inserted at the time of surgery (porous coated and HA coated)
Other Names:
  • Biomet, Oxford Uni Knee, cementless femur
  • Biomet, Oxford Uni Knee, cementless tibial bearing tray

Detailed 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.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

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
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00679120

Contacts
Contact: Maiken Stilling, MD 0045 89497466 mm-p@dadlnet.dk

Locations
Denmark
Orthopaedic Center, Aarhus University Hospital Recruiting
Aarhus, Denmark, 8000
Contact: Maiken Stilling, MD    0045 89497466    mm-p@dadlnet.dk   
Contact: Kjeld Soballe, MD, Prof.    0045 89497425    kjelsoeb@rm.dk   
Sub-Investigator: Maiken Stilling, MD, PhD         
Sub-Investigator: Frank Madsen, MD         
Sub-Investigator: Anders Odgaard, MD, DMSc         
Sub-Investigator: Per Wagner Kristensen, MD         
Sub-Investigator: Lone Romer, MD         
Principal Investigator: Kjeld Soballe, MD, DMSc         
Sponsors and Collaborators
University of Aarhus
Aarhus University Hospital
Vejle Hospital
Biomet, Inc.
Investigators
Principal Investigator: Kjeld Soballe, MD, Prof. Orthopaedic Center, Aarhus University Hospital, Tage-Hansens Gade 2, 8000 Aarhus C, Denmark
  More Information

No publications provided

Responsible Party: University of Aarhus
ClinicalTrials.gov Identifier: NCT00679120     History of Changes
Other Study ID Numbers: 20070258
Study First Received: May 14, 2008
Last Updated: March 20, 2012
Health Authority: Denmark: The Danish National Committee on Biomedical Research Ethics

Keywords provided by University of Aarhus:
Unicompartmental osteoarthrosis
RSA
Bone-remodelling

Additional relevant MeSH terms:
Osteoarthritis
Osteoarthritis, Knee
Arthritis
Joint Diseases
Musculoskeletal Diseases
Rheumatic Diseases

ClinicalTrials.gov processed this record on July 22, 2014