Study to Evaluate the Safety and Efficacy of OR3O™ Dual Mobility System vs. Conventional Single Bearing Design Total Hip System

The purpose of this study is to compare OR3O™ Dual Mobility System to a conventional, single-bearing design Total Hip System in subjects who undergo Primary THA. Data collected in this study will be used to support National Medical Products Administration (NMPA) regulatory approval of OR3O™ Dual Mobility System in China as well as to support and maintain product registration in global markets.

Primary Objective: Assess safety and efficacy of the OR3O™ Dual Mobility System in Primary THA at 1 year postoperative.

Secondary Objective(s): Assess safety and efficacy of the OR3O™ Dual Mobility System and compatible components in Primary THA up to 2 years after surgery.

Other Objective(s): Assess the hip dislocation and hospital readmission up to 2 years after device implantation.

4 study sites in China.


Eligibility Criteria:
Inclusion Criteria:

* Subject is a suitable candidate for implanting the OR3O™ Dual Mobility System or single-bearing design Total Hip System in primary total hip replacement in the Investigator's judgement.
* Subject is skeletally mature in the Investigator's judgement.
* Subject is 18 - 80 years old (inclusive).
* Subject is receiving total hip replacement for the first time on the affected hip.
* Subject has any of the following conditions:

  * Advanced degeneration of the hip joint as a result of degenerative, post-traumatic, or rheumatoid arthritis(RA);
  * Fracture or avascular necrosis of the femoral head;
  * All forms of osteoarthritis(OA);
  * Patients with hips at risk of dislocation;
  * Femoral neck fracture or proximal hip joint fracture.
* Subject provides written informed consent for study participation using an Ethical Committee (EC) approved consent form before any study procedures are performed, including pre-operative data review and/or collection of data on electronic Case Report Forms (eCRFs).
* Subject is willing and able to participate in required follow-up visits and is able to complete study activities.
* Subjects with preoperative HHS ≤ 79 (fair or worse category).

Exclusion Criteria:

* Subject has conditions that would eliminate or tend to eliminate adequate implant support or prevent the use of an appropriately-sized implant, e.g.:

  * blood supply limitations;
  * insufficient quantity or quality of bone support, e.g., osteoporosis, metabolic disorders which may impair bone formation, radioactive bone disease, tumor around hip joint, and osteomalacia;
  * infections or other conditions which may lead to increased bone resorption.
* Subject has dysplasia of hip joint with CROWE Grade III, IV.
* Subject has weak constitution or failing to endure the surgery due to other diseases of the body.
* Subject has bodily disease(s) that may interfere with THA survival or outcome.
* Subject has life expectancy of less than 2 years.
* Subject has mental or neurological conditions which impair the subject's ability or willingness to restrict activities that may put the affected limb at risk.
* Subject has physical conditions or activities which tend to place extreme loads on implants, e.g., Charcot joints, muscle deficiencies, multiple joint disabilities.
* Subject has neuromuscular dysfunctions (paralysis, myolysis and abductor muscle weakness) which will cause unstable hip joint or abnormal gait after surgery.
* Subject has a mental or neurological condition that would pre-empt their ability or willingness to participate in the study including mental illness, mental retardation, drug or alcohol abuse.
* Subject has an active infection - systemic or at the site of intended surgery.
* Subject has a Body Mass Index ≥ 40.0 kg/m².
* Subject has a known allergy to any component of the devices used in the study.
* Subject is pregnant or breast feeding.
* Subject is entered in another investigational drug, biologic, or device study within 30 days of active study participation.
* Subjects that are expected with poor compliance.
* Subjects with complications of other diseases are limited to participate in the research, not able to comply with the follow-up or have impact on scientific integrity.
* Subjects with preoperative HHS ≥ 80 (good to excellent category).
* Subject has other diseases or conditions that investigator considers not appropriate to participate in the study.