Wear and Migration in the Corin Mini-Hip/Metafix and ECIMA Polyethylene

Study Overview
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Brief Summary
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The primary objective of this study is to determine whether the Mini Hip (Corin, U.K.) femoral component has a predictable and stable migration pattern (mean migration of the femoral component in three-dimensions,in mm) over a three year period, compared to a conventional cementless stem (Metafix, Corin, U.K.). The secondary objectives of this study are to determine whether the Trinity (Corin, U.K.) acetabular component has a predictable and stable migration pattern over a three year period and to measure the linear wear of femoral head into the ECIMA Highly Cross-linked polyethylene.

Official Title
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RSA-measured in Vivo Wear, Migration and Micromotion in the Corin Mini-Hip/Metafix and ECIMA Polyethylene.

Conditions
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Hip Osteoarthritis

Intervention / Treatment
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* Device: MiniHip (Corin U.K.)
* Device: Metafix (Corin, U.K)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Women and men between the ages of 18 and 65 years old. Scheduled to receive a hip replacement Willing and able to give informed consent for participation in the study. Diagnosed with hip osteoarthritis Able (in the investigators opinion) and willing to comply with all study requirements. Willing to allow his/her General Practitioner and consultant, if appropriate, to be notified of participation in the study Exclusion Criteria: The participants may not enter the study if ANY of the following apply: Inflammatory arthropathy, osteoporosis or deformities of the proximal femur. Significant comorbidities that would make follow up difficult or uncomfortable Any other significant disease or disorder which, in the opinion of the investigator, may either put the participant at risk due to participation in the study, may influence the result of the study, or the participants ability to participate in the study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: MiniHip (Corin U.K.)<br>MiniHip (Corin U.K.) femoral component | Device: MiniHip (Corin U.K.)<br>* MiniHip (Corin U.K.) femoral component<br>|
| Active Comparator: Metafix (Corin, U.K)<br>Metafix (Corin, U.K) conventional cementless stem | Device: Metafix (Corin, U.K)<br>* Metafix (Corin, U.K) conventional cementless stem<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Radiostereometric Analysis (RSA) measured migration (mm) | The images taken at each time point will be compared with the baseline to assess implant migration. Therefore the outcome is change in implant position measured using RSA. | Measured pre-operatively (baseline) and at 3, 6, 12, 18, 24 and 36 months post-operatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Dynamically Inducible Micromotion DIMM (mm) | Using RSA this compares standard images with images taken in a single leg stance. | Measured at 6, 12, 24 and 36 months post-operatively | 
| Implant failure for femoral and acetabular components | Follow up assessment will monitor for signs of implant failure. | Observed at 3, 6, 12, 18, 24 and 36 months post-operatively | 
| Change in Oxford Hip Score | A PROM to assess patient benefit. | Measured pre-operatively (baseline) and at 3, 6, 12, 18, 24 and 36 months post-operatively | 
| Change in Harris Hip Score | A clinician recorded outcome score to assess functional improvement. | Measured pre-operatively (baseline) and at 3, 6, 12, 18, 24 and 36 months post-operatively |