An MRI Investigation of Soft Tissues in Total Hip Arthroplasty

Study Overview
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Brief Summary
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Retrospective study to comply with FDA's post-market surveillance order. The purpose of the study is to contact patients who have received a Biomet metal-on-metal product as their primary total hip arthroplasty device. Patients who have not been revised prior to contact will be asked to submit to a blood draw, clinical exam and MRI.

Detailed Description
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This study has been designed to estimate the prevalence of soft tissue changes following primary THA surgery in patients having received one of five Biomet implant types; a MOP primary THA, an M2a 38, M2a Taper, M2a Ringloc and M2a Magnum MOM primary THA device in 308-436 total patients at four centers. The primary objective of the study is to estimate the prevalence of soft tissue changes in unbiased MoM and MoP samples. Secondary objectives are to evaluate whether the occurrence of soft tissue changes is related to any of several potential covariates including patient and implant characteristics and time in situ.

Official Title
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An MRI Investigation of Soft Tissues in Total Hip Arthroplasty

Conditions
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Tissue Reaction, Elevated Blood Ion Levels

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patient meets the sampling plan requirements Exclusion Criteria: patient is contraindicated for MRI patient fails to consent for the study
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| pre-THA<br>Patients who are planned but have not yet received a total hip arthroplasty. No intervention or treatment - blood draw only to be used as a surrogate baseline for metal ion exposure. | |
| Metal-on-Poly<br>Patients receiving a Biomet metal on poly hip implanted between January 1, 2003 and December 31, 2006. | |
| M2a Magnum hip<br>Patients receiving a Biomet M2a Magnum hip implanted between January 1, 2006 and January 1, 2011. | |
| M2a38 hip<br>Patients receiving a Biomet metal on metal M2a38 hip implanted between January 1, 2004 and December 31, 2006. | |
| M2a Ringloc hip<br>Patients receiving a Biomet M2a Ringloc metal on metal hip implanted between January 1, 2002 and December 31, 2004. | |
| M2a Taperloc hip<br>Patients receiving a Biomet M2a Taperloc metal on metal hip implanted between January 1, 2002 and December 31, 2003. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of symptomatic and asymptomatic Metal-on-Metal and Metal-on-Poly patients (via a proportion) with a soft tissue mass | Compare the proportion of symptomatic and asymptomatic Metal-on-Metal patients with a soft tissue mass to the proportion of Metal-on-Poly patients with soft tissue masses. | patients 3 years post-implantation up to 6 years post implantation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Metal ion concentrations in whole blood and serum | Determine metal ion concentrations in whole blood and serum and assess whether findings correlate to any other variable such as pain, implant type, time since surgery and presence of ALTR. | 1-10 year post implantation, depending on cohort |