Large Head X3 Study

Study Overview
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Brief Summary
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The purpose of this study is to explore the benefit of X3 polyethlene inserts with larger diameter heads used in the Japanese population. Range of Motion (ROM) and lift-off distance for both 28mm, 32mm and 36mm in patients will be examined intraoperatively by using the Stryker computerized tomography (CT) based Navigation system. Another aspect of this study is to observe wear resistance performance of X3 over historical liner existing highly crosslinked polyethylene.

Official Title
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The Effect of Large Diameter Head to Prevent Dislocation, and of 3 rd Generation Highly Crosslinked Polyethylene to Reduce Wear in Computer Assisted Total Hip Arthroplasty.

Conditions
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Degenerative Joint Disease

Intervention / Treatment
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* Device: Trident Acetabular X3 Insert


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patient who is a candidate for primary total hip arthroplasty (THA) with cementless acetabular and femoral components. Patient who has diagnosis of degenerative joint disease and no bacterial infectious disease. Patient whose age is 20 or over. Patient who signed an Institutional Review Board (IRB)-approved, study specific Informed Patient Consent Form. Patient who is willing and able to comply with postoperative scheduled evaluations. Exclusion Criteria: Patient who has a bacterial infectious disease or has a high risk of a bacterial infection. Patient who requires revision surgery of a previously implanted total hip arthroplasty. Patient who is morbidly obese, defined as having a Body Mass Index (BMI) > 45. Patient who is or may be pregnant female. Patient who has a neuromuscular or neurosensory deficiency, which limits ability to evaluate the safety and efficacy of the device. Patient with diagnosed systemic disease (i.e. Paget's disease, renal osteodystrophy). Patient who is immunologically suppressed or receiving chronic steroids. Patient who is judged ineligible with specific reason by primary doctor.

Ages Eligible for Study
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Minimum Age: 20 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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Trident Acetabular X3 Insert<br>28mm, 32mm and 36mm liner | Device: Trident Acetabular X3 Insert<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Range of Motion(ROM) (Degree) | Measure and compare the ROM using femoral head trials of 36mm- and 28mm-diameter during intraoperative confirmation. | Intraoperative | 
| Lift Off Distance in Dislocation Maneuver(mm) | Measure and compare the lift off distance in dislocation maneuver using femoral head trials of 36mm- and 28mm-diameter during intraoperative confirmation. | Intraoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Wear Rate(%) | Retrospective comparison of the wear amount over time between X3 liner and Crossfire insert. | 1 year, 2 years, 3 years and 5 years after surgery |