Evaluate the Safety and Effectiveness of the Polymotion Hip Resurfacing (PHR) System Compared to Total Hip Arthroplasty

Inclusion Criteria

• •In order to be eligible to participate in this study, subjects must meet all of the following criteria:
• •1. Requires primary hip resurfacing arthroplasty due to:
• •1. non-inflammatory arthritis (degenerative joint disease) such as osteoarthritis, traumatic arthritis, or
• •2. mild dysplasia/developmental dislocation of the hip (DDH) up to Crowe Grade 1.
• •2. Harris Hip Score \< 70 points.
• •3. Skeletally mature, age ≥21 and \<65 years.
• •4. Physically and mentally able and willing to comply with the Protocol, including the ability to read and complete required forms and willing and able to adhere to the scheduled follow-up visits and requirements of the Protocol.
• •Subjects who meet any of the following criteria will be excluded from participating in this study:
• •1. Inadequate bone stock or bone quality to support the device based on a Canal-Bone Ratio (CBR-7) of \>0.45.0F
• •2. Severe osteopenia, a medical history or increased risk of severe osteoporosis or severe osteopenia, a history of fragility fracture, and other conditions that lead to increased bone resorption
• •3. Osteonecrosis or avascular necrosis (AVN)
• •4. Multiple cysts of the femoral head (\> 1cm) or cysts crossing the head-neck junction
• •5. Metabolic disorders which may impair bone formation (e.g., osteomalacia, osteogenesis imperfecta, parathyroid disease, rickets, etc.)
• •6. Severe femoral head deformities that will prevent fixation of the prosthetic resurfacing femoral head
• •7. Inflammatory arthritis such as rheumatoid arthritis (RA)
• •8. Severe proximal femoral rotational deformity in whom appropriate combined anteversion of femoral-acetabular construct is unachievable
• •9. Severe acetabular dysplasia/development dislocation of the hip, defined as Crowe Grade ≥ 2
• •10. Previous surgical intervention on index hip (e.g., treatment of hip fracture, arthroscopy)
• •11. Severe medical comorbidities, including:
• •1. severe cardiopulmonary disease,
• •2. congestive heart failure,
• •3. severe liver or kidney dysfunction,
• •4. end-stage renal disease,
• •5. severe uncontrolled diabetes,
• •6. history of IV drug use,
• •7. history of hypercoagulable state or pulmonary embolism,
• •8. severe lumbar spinal stenosis,
• •9. vascular insufficiency, muscular atrophy, or neuromuscular disease severe enough to compromise implant stability or post-operative recovery,
• •10. neuropathic arthropathy (Charcot joint),
• •11. immunosuppression or other immunodeficiency disorders, e.g., diseases such as Acquired Immune Deficiency Syndrome (AIDS) or post-organ transplant and on high doses of corticosteroids.
• •12. Incompetent or deficient soft tissue surrounding the joint (e.g., hip abductor muscle deficiency)
• •13. BMI \> 40
• •14. Active or suspected infection in or around the hip joint
• •15. Known or suspected metal sensitivity (e.g., jewelry) or allergy to any implant materials
• •16. Pregnant or plan to become pregnant during the study duration
• •17. Current smoker