The primary objective of this study is to obtain implant survivorship and clinical outcomes data for the commercially available G7 BiSpherical Acetabular Shell.

The G7 BiSpherical Acetabular Shell belongs to the G7 multi-bearing platform. It was developed to provide an additional surgical option for patients in need of a total hip replacement. The aim of the G7 BiSpherical Acetabular Shell is to increase hip function while reducing pain.

This study is a multicenter, prospective, non-randomized, non-controlled post market surveillance study involving orthopedic surgeons skilled in hip arthroplasty procedures. A minimum of 4 and a maximum of 5 sites will be involved in this study. This number of clinical centers will permit assessment of consistency among a multitude of investigators. 140-175 implants will be included into the study. Each site will be allowed to enroll 35 patients. All potential study subjects will be required to participate in the Informed Consent Process.

The safety and performance of the G7 BiSpherical Acetabular Shell will be assessed as following: implant survivorship based on revision with removal of the study device; safety based on incidence and frequency of adverse events; and clinical efficacy measured by overall pain and function, quality of life data and radiographic evaluation.

Inclusion Criteria:

• Patient capable of understanding the surgeon's explanations and following his instructions, able and willing to participate in the follow-up program and who gave consent to take part in the study.
• Patient aged of 18 years or more whose skeleton reached bone maturity.
• Noninflammatory degenerative joint disease including osteoarthritis and avascular necrosis.
• Rheumatoid arthritis.
• Correction of functional deformity.
• Treatment of non-union, femoral neck fracture, and trochanteric fractures of the proximal femur with head involvement, unmanageable by other techniques.
• Revision procedures where other treatment or devices have failed.

Inclusion criteria specific for patients receiving the G7 BiSpherical Shell with the G7 Freedom Constrained Liner:

• The Biomet G7 Freedom Constrained Liner is indicated for use as a component of a total hip prosthesis in primary and revision patients at high risk of dislocation due to a history of prior dislocation, bone loss, joint or soft tissue laxity, neuromuscular disease, or intraoperative instability, and for whom all other options to con-strained acetabular components have been considered.

Exclusion Criteria:

Absolute exclusion criteria include:

• Infection, sepsis, osteomyelitis.

Relative exclusion criteria include:

• Uncooperative patient or patient with neurologic disorders who is incapable of following directions.
• Osteoporosis.
• Metabolic disorders which may impair bone formation.
• Osteomalacia.
• Distant foci of infections which may spread to the implant site.
• Rapid joint destruction, marked bone loss or bone resorption apparent on roentgenogram.
• Vascular insufficiency, muscular atrophy or neuromuscular disease.
• Patient unwilling or unable to give consent, or to comply with the follow-up program.
• Patient known to be pregnant or breastfeeding.
• Patient presenting any condition that would, in the judgment of the Investigator, place the patient at undue risk or interfere with the study.
• Patient institutionalized or known drug abuser or alcoholic or anyone who cannot understand what is required of them.
• Patient belonging to a vulnerable population.

Exclusion criteria specific for patients receiving the G7 BiSpherical Shell with the G7 Freedom Constrained Liner:

• Bone or musculature compromised by disease, infection, or prior implantation that cannot provide adequate support or fixation for the prosthesis.

Patients in need of a Total Hip Arthroplasty (primary or revision) which receive the G7 BiSperical Acetabular Shell and who meet all of the inclusion and none of the exclusion criteria.