Migration and Head Penetration of Vitamin-E Diffused Cemented Polyethylene Cup in Total Hip Arthroplasty

Study Overview
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Brief Summary
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In vitro, Vitamin-E diffused, highly cross-linked polyethylene (PE) have been shown to have superior wear resistance and improved mechanical properties as compared to that of standard highly cross-linked PE. There are as of yet no published studies with vitamin-E diffused PE although several trials are ongoing. All of these trials use uncemented acetabular cups intended for biological fixation. In many countries the standard fixation method for the acetabular component is bone-cement. The Vitamin-E used in implants is alfa-tocopherol, a lipid-soluble antioxidant with oily consistency; theoretically affecting cemented fixation when used in acetabular components. The aim of the study is to compare migration, linear wear and clinical results between two types of cemented acetabular cups.

Official Title
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Migration and Head Penetration of Vitamin-E Diffused Cemented Polyethylene Cup Compared to Standard Cemented Cup in Total Hip Arthroplasty. A Randomized, Single-blinded, Clinical Trial

Conditions
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Total Hip Arthroplasty

Intervention / Treatment
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* Device: Standard polyethylene acetabular component
* Device: Vitamin-E diffused polyethylene acetabular component


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Primary osteoarthritis of the hip Willingness and ability to follow study-protocol Exclusion Criteria: Inflammatory arthritis or secondary osteoarthritis. Type C (stove pipe) femur Abnormal femoral or pelvic anatomy after hip dysplasia, not suitable for implantation of components Treatment with bisphosphonates, cortisol or cytostatic drugs 6 months prior to surgery Ongoing oestrogen treatment Not suited for the study for other reason (surgeons preference)

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Vitamin-E group<br>Vitamin-E diffused polyethylene | Device: Vitamin-E diffused polyethylene acetabular component<br>* Patients will undergo total hip arthroplasty using a cemented acetabular component diffused with Vitamin-E<br>|
| Active Comparator: Control group<br>Standard polyethylene | Device: Standard polyethylene acetabular component<br>* Patients will undergo total hip arthroplasty using a standard cemented acetabular component<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cup migration | The primary outcome measure is migration of the cup at 2 years measured with radiostereometry (RSA) as proximal migration. | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Linear wear | Linear head penetration measured with RSA at 2 years | 2 years | 
| Linear wear | Linear head penetration measured with RSA at 4 years | 4 years | 
| Osteolysis | Development of radiolucent lines between bone and cement around the cup. | 10 years | 
| Osteolysis | Development of radiolucent lines between bone and cement around the cup. | 2 years | 
| Functional outcome | Hip function measured with Harris hip score | 2 years | 
| Complication rate | All hip-related complications and revision of implants | 10 years | 
| Cup migration total | Migration of the cup at 2 years measured with radiostereometry (RSA) as maximum total point motion (MTPM). | 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Total hip arthroplasty, Cemented acetabular cup, Vitamin-E, Radiostereometry, Fixation of cemented acetabular component in total hip arthroplasty