Large Head X3 Study

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.

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.

Inclusion Criteria:

1. Patient who is a candidate for primary total hip arthroplasty (THA) with cementless acetabular and femoral components.
2. Patient who has diagnosis of degenerative joint disease and no bacterial infectious disease.
3. Patient whose age is 20 or over.
4. Patient who signed an Institutional Review Board (IRB)-approved, study specific Informed Patient Consent Form.
5. Patient who is willing and able to comply with postoperative scheduled evaluations.

Exclusion Criteria:

1. Patient who has a bacterial infectious disease or has a high risk of a bacterial infection.
2. Patient who requires revision surgery of a previously implanted total hip arthroplasty.
3. Patient who is morbidly obese, defined as having a Body Mass Index (BMI) > 45.
4. Patient who is or may be pregnant female.
5. Patient who has a neuromuscular or neurosensory deficiency, which limits ability to evaluate the safety and efficacy of the device.
6. Patient with diagnosed systemic disease (i.e. Paget's disease, renal osteodystrophy).
7. Patient who is immunologically suppressed or receiving chronic steroids.
8. Patient who is judged ineligible with specific reason by primary doctor.