Cemented Versus Cementless Unicompartmental Knee Arthroplasty
Study Details
Study Description
Brief Summary
Unicompartmental knee replacement for selected cases of osteoarthritis is less invasive than total knee replacement. It gives better range of movement; patients stay for shorter time in the hospital and have a more natural feel than total knee replacement. Usually, the implant is fixed in the bone using bone cement. However, there are potential disadvantages of using bone cement. The operation takes longer; cement can get squeezed out into the surrounding tissues and may interfere with function. To avoid these problems, the implant can be fixed without cement. Cementless components have a special coating to encourage bone in-growth and fixation. Although the investigators believe cementless fixation will be at least as good as cemented fixation, there is a risk that it could be worse and might result in loosening.
The aim of this study is therefore to compare the outcome of cemented and cementless unicompartmental knee replacement.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Detailed Description
Design: A prospective, randomised trial to compare the outcome of cemented and cementless unicompartmental knee replacement.
Size: 40 subjects in total will be recruited with 20 in each arm.
Methods: Patients will be recruited from the routine waiting list for unicompartmental knee replacement at the Nuffield Orthopaedic Centre. All subjects will have the procedure explained and be fully consented prior to the procedure.
Randomisation: Patients will be randomly allocated to receive either a cemented or cementless Oxford Unicompartmental Knee Replacement. This will be performed using a randomisation program based on optimisation (Minim). Subjects will be stratified according to sex and age.
Operation: All subjects will undergo the same surgical approach. 0.8mm Tantalum marker balls will be placed at standardised sites on the femur and tibia in all cases. All cemented components will be secured using the same cement. Cementless components have a hydroxy-appatite coating to facilitate bone ingrowth.
Follow-up: All patients will be followed up at 0, 3, 6, 12, 24, 60, and 120 months with clinical and radiological assessment. Clinical assessment will involve documentation with the Oxford Knee Score. Patients will undergo radiostereometric analysis and fluoroscopy to study implant migration and occurence of radiolucency, respectively.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: Cementless Oxford Unicompartmental Knee Arthroplasty Phase III Cementless Oxford Unicompartmental Knee Replacement (Biomet) |
Device: Cementless Oxford Unicompartmental Knee Arthroplasty
All patients will undergo the same surgical approach. 0.8mm diameter tantalum marker balls will be placed in the tibia and femur in all cases. Cementless components have a hydroxy-appatite coating to facilitate bone ingrowth. The cementless femoral component also has a smaller second peg, located anteriorly to the larger central peg that is also present of the cemented femoral component.
Other Names:
|
| Active Comparator: Cemented Oxford Unicompartmental Knee Arthroplasty Phase III Cemented Oxford Unicompartmental Knee Replacement (Biomet) |
Device: Cemented Oxford Unicompartmental Knee Arthroplasty
All patients will undergo the same surgical approach. 0.8mm diameter tantalum marker balls will be placed in the tibia and femur in all cases. All cemented components will be secured using the same cement.
Other Names:
|
Outcome Measures
Primary Outcome Measures
- Radiostereometric Analysis Examination - Translations [Patients will be examined immediately (0 months) post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional translations will be measured in millimetres.
- Radiostereometric Analysis Examination - Translations [Patients will be examined 3 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional translations will be measured in millimetres.
- Radiostereometric Analysis Examination - Translations [Patients will be examined 6 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional translations will be measured in millimetres.
- Radiostereometric Analysis Examination - Translations [Patients will be examined 12 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional translations will be measured in millimetres.
- Radiostereometric Analysis Examination - Translations [Patients will be examined 24 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional translations will be measured in millimetres.
- Radiostereometric Analysis Examination - Translations [Patients will be examined 60 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional translations will be measured in millimetres.
- Radiostereometric Analysis Examination - Translations [Patients will be examined 120 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional translations will be measured in millimetres.
- Radiostereometric Analysis Examination - Rotations [Patients will be examined immediately (0 months) post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional rotations will be measured in degrees.
- Radiostereometric Analysis Examination - Rotations [Patients will be examined at 3 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional rotations will be measured in degrees.
- Radiostereometric Analysis Examination - Rotations [Patients will be examined at 6 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional rotations will be measured in degrees.
- Radiostereometric Analysis Examination - Rotations [Patients will be examined at 12 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional rotations will be measured in degrees.
- Radiostereometric Analysis Examination - Rotations [Patients will be examined at 24 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional rotations will be measured in degrees.
- Radiostereometric Analysis Examination - Rotations [Patients will be examined at 60 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional rotations will be measured in degrees.
- Radiostereometric Analysis Examination - Rotations [Patients will be examined at 120 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Three-dimensional rotations will be measured in degrees.
- Radiostereometric Analysis Examination - Maximum Total Point Motion [Patients will be examined immediately (0 months) post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Maximum Total Point Motion (MTPM - defined as the length of the translation vector of the point of the component model that has migrated the most) will be measured in millimetres.
- Radiostereometric Analysis Examination - Maximum Total Point Motion [Patients will be examined at 3 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Maximum Total Point Motion (MTPM - defined as the length of the translation vector of the point of the component model that has migrated the most) will be measured in millimetres.
- Radiostereometric Analysis Examination - Maximum Total Point Motion [Patients will be examined at 6 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Maximum Total Point Motion (MTPM - defined as the length of the translation vector of the point of the component model that has migrated the most) will be measured in millimetres.
- Radiostereometric Analysis Examination - Maximum Total Point Motion [Patients will be examined at 12 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Maximum Total Point Motion (MTPM - defined as the length of the translation vector of the point of the component model that has migrated the most) will be measured in millimetres.
- Radiostereometric Analysis Examination - Maximum Total Point Motion [Patients will be examined at 24 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Maximum Total Point Motion (MTPM - defined as the length of the translation vector of the point of the component model that has migrated the most) will be measured in millimetres.
- Radiostereometric Analysis Examination - Maximum Total Point Motion [Patients will be examined at 60 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Maximum Total Point Motion (MTPM - defined as the length of the translation vector of the point of the component model that has migrated the most) will be measured in millimetres.
- Radiostereometric Analysis Examination - Maximum Total Point Motion [Patients will be examined at 120 months post surgery.]
Patients will have weight-bearing stereoradiographs. These stereoradiographs will be analysed using model-based radiostereometric analysis which will allow the migration of the components relative to the bone to be determined. Maximum Total Point Motion (MTPM - defined as the length of the translation vector of the point of the component model that has migrated the most) will be measured in millimetres.
- Radiographic Examination [Patients will be examined immediately (0 months) post surgery.]
Fluoroscopic imaging will be used to study the occurence of radiolucencies beneath the components. Anteroposterior radiographs will be analysed to assess the presence and position of radiolucencies. Radiolucencies will be graded as either 'no radiolucency present', 'partial radiolucency', or 'complete radiolucency'.
- Radiographic Examination [Patients will be examined at 3 months post surgery.]
Fluoroscopic imaging will be used to study the occurence of radiolucencies beneath the components. Anteroposterior radiographs will be analysed to assess the presence and position of radiolucencies. Radiolucencies will be graded as either 'no radiolucency present', 'partial radiolucency', or 'complete radiolucency'.
- Radiographic Examination [Patients will be examined at 6 months post surgery.]
Fluoroscopic imaging will be used to study the occurence of radiolucencies beneath the components. Anteroposterior radiographs will be analysed to assess the presence and position of radiolucencies. Radiolucencies will be graded as either 'no radiolucency present', 'partial radiolucency', or 'complete radiolucency'.
- Radiographic Examination [Patients will be examined at 12 months post surgery.]
Fluoroscopic imaging will be used to study the occurence of radiolucencies beneath the components. Anteroposterior radiographs will be analysed to assess the presence and position of radiolucencies. Radiolucencies will be graded as either 'no radiolucency present', 'partial radiolucency', or 'complete radiolucency'.
- Radiographic Examination [Patients will be examined at 24 months post surgery.]
Fluoroscopic imaging will be used to study the occurence of radiolucencies beneath the components. Anteroposterior radiographs will be analysed to assess the presence and position of radiolucencies. Radiolucencies will be graded as either 'no radiolucency present', 'partial radiolucency', or 'complete radiolucency'.
- Radiographic Examination [Patients will be examined at 60 months post surgery.]
Fluoroscopic imaging will be used to study the occurence of radiolucencies beneath the components. Anteroposterior radiographs will be analysed to assess the presence and position of radiolucencies. Radiolucencies will be graded as either 'no radiolucency present', 'partial radiolucency', or 'complete radiolucency'.
- Radiographic Examination [Patients will be examined at 120 months post surgery.]
Fluoroscopic imaging will be used to study the occurence of radiolucencies beneath the components. Anteroposterior radiographs will be analysed to assess the presence and position of radiolucencies. Radiolucencies will be graded as either 'no radiolucency present', 'partial radiolucency', or 'complete radiolucency'.
- Clinical Assessment [Patients will be assessed pre-operatively.]
Clinical assessment will involve documentation with the Oxford Knee Score. The score will be calculated on a scale of 0 (worst) to 48 (best).
- Clinical Assessment [Patients will be assessed at 12 months post surgery.]
Clinical assessment will involve documentation with the Oxford Knee Score. The score will be calculated on a scale of 0 (worst) to 48 (best).
- Clinical Assessment [Patients will be assessed at 24 months post surgery.]
Clinical assessment will involve documentation with the Oxford Knee Score. The score will be calculated on a scale of 0 (worst) to 48 (best).
- Clinical Assessment [Patients will be assessed at 60 months post surgery.]
Clinical assessment will involve documentation with the Oxford Knee Score. The score will be calculated on a scale of 0 (worst) to 48 (best).
- Clinical Assessment [Patients will be assessed at 120 months post surgery.]
Clinical assessment will involve documentation with the Oxford Knee Score. The score will be calculated on a scale of 0 (worst) to 48 (best).
Eligibility Criteria
Criteria
Inclusion Criteria:
-
Healthy Subjects with osteoarthritis of knee fulfilling the standard indications for an Oxford Unicompartmental Knee Replacement.
-
American Society of Anaesthesiologists (ASA) Score of 1 to 3.
Exclusion Criteria:
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Subjects with severe limiting systemic illness (i.e. ASA > 3).
-
Subjects who are too large for radiostereometric analysis to be carried out.
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Subjects who have had previous open surgery or anterior cruciate ligament (ACL) reconstruction on the same knee.
Contacts and Locations
Locations
No locations specified.Sponsors and Collaborators
- Oxford University Hospitals NHS Trust
Investigators
- Principal Investigator: David W Murray, MA, MD, FRCS, University of Oxford
Study Documents (Full-Text)
None provided.More Information
Additional Information:
Publications
None provided.- PID7088