A Prospective RSA and Clinical Evaluation of the Trident II Acetabular Cup

A Prospective RSA and Clinical Evaluation of the Trident II Acetabular Cup

The objective of this study is to use radiostereometric analysis (RSA) and clinical outcome measures to evaluate early post-operative implant stability and the clinical performance of Stryker's Trident II Acetabular Cup.

The proposed study is a prospective evaluation of data from patients undergoing primary total hip arthroplasty using the Trident II acetabular cup. Fifty patients will be recruited for this study. All patients that qualify for the study per the inclusion-exclusion criteria and provide written informed consent will receive the Trident II acetabular cup and RSA beads. Implant stability, through RSA, will be measured throughout the first two postoperative (post-op) years per the following schedule: immediate post-op and 6 weeks, 3 months, 6 months, 1 year, and 2 years following surgery. Patients will be discharged and seen for follow-up assessments as per standard of care. Adverse events that are related to the index joint will be collected. Health outcome questionnaires will be collected. The health outcome questionnaires will include: EQ-5D, HOOS JR and Harris Hip Score. Health outcome questionnaires will be completed pre-operatively and again at 6 weeks, 3 months, 6 months, 1 year and 2 years following surgery. Conventional x-ray analysis will be performed pre-operatively and again at 6 weeks, 1 year and 2 years following surgery.

Inclusion Criteria:

1. Symptomatic arthritis of the hip indicating surgical intervention
2. Scheduled to undergo a primary total hip arthroplasty
3. Patient is a candidate for the Trident II acetabular cup in accordance with product labeling -

Exclusion Criteria:

1. Patients less than 18 years of age, or older than 85 years of age.
2. Severe hip dysplasia (Crowe Type III or IV) in the affected hip
3. History of congenital dislocation
4. Prior arthroplasty of the affected hip
5. Active or prior infection of the affected hip
6. Morbid obesity (BMI > 40)
7. Medical condition precluding major surgery
8. Severe osteoporosis
9. Neuromuscular impairment
10. Patients with known allergy to metals
11. Pregnancy
12. Patients on dialysis or creatinine > 2.0
13. Patient is immuno-suppressed -