The study will evaluate the radiographs (x-rays) of 100 patients with a TriFIT total hip at 2 weeks, 3 months, 6 months, 12 months, and yearly following surgery to see if there has been any movement or wear in the hip stem over the course of the study. The study will also record clinical data on each patient using various functional tests and questionnaires at the same intervals.

The present study will prospectively recruit 100 patients scheduled for elective total hip replacement with Corin's TriFIT Hip System at the Ottawa Hospital - General Campus. As part of their clinical care, patients routinely undergo a clinical examination and have had radiographs taken at 2 weeks, 3 months, 6 months, 12 months, and yearly following surgery. Using specialized software, radiographs from each interval will be examined to assess femoral stem migration and joint wear patterns. Femoral stem migration will be assessed using computer-assisted software. The study will also assess the rate of implant failure during the first two post-operative years. Clinical assessments and questionnaires will also be completed during each of the follow-up intervals.

Inclusion Criteria:

• Patients scheduled for primary, unilateral total hip replacement (THR) with no previous history of hip replacement and/or fracture surgery.
• Patients with arthritis secondary Noninflammatory Degenerative Joint Diseases (NIDJD), including osteo/degenerative arthritis, congenital hip dysplasia, and avascular necrosis.
• Patients who do not meet any of the exclusion criteria.

Exclusion Criteria:

• Patients with previous fusions, acute femoral neck fractures, above knee amputations, or previous total knee replacement.
• Patients who had previously undergone an ipsilateral hemi resurfacing, total resurfacing, total bipolar, unipolar or total hip replacement device.
• Patients with neuropathic joints.
• Patients who required structural bone grafts.
• Patients with an ipsilateral girdlestone.
• Patients who otherwise met the study criteria, but for which appropriate clinical follow-up data is not available (i.e. patients deceased prior to 2-year follow-up, patients refused to return for follow-up).

The first 100 patients Dr. Paul Beaule undergoing a total hip replacement with Corin's TriFIT Total Hip replacement system that meet the eligibility requirements and consent to do the study.