Continuum™ Metal Bearing System in Total Hip Arthroplasty

The subject of this clinical investigation is the Continuum Metal Bearing THA System in
primary total hip arthroplasty. This system consists of a cementless modular Trabecular
Metal™ (TM) Continuum Acetabular Shell, a modular Metasul Taper liner, and a modular Metasul
femoral head. The characteristics of this THA system may allow for reduction in wear and
osteolysis as compared to other approved and marketed THA systems and thus increase the
expected implant life.

In total, 3 centers will be involved. This number of clinical sites will permit assessment of
the consistency among a multitude of investigators. A total number of 100 subjects will be
included in the study. It is anticipated that each clinical site will enroll 10 to 45
eligible study subjects, who have provided written informed consent.

Inclusion Criteria:

- Patient is 18 to 75 years of age, inclusive.

- Patient is skeletally mature.

- Patient qualifies for primary unilateral or bilateral total hip arthroplasty (THA)
based on physical exam and medical history including the following:

- Avascular necrosis (AVN) Osteoarthritis (OA)

- Inflammatory arthritis (i.e. Rheumatoid arthritis)

- Post-traumatic arthritis

- Patient has no history of previous prosthetic replacement device (any type, including
surface replacement arthroplasty, endoprosthesis, etc.) of the affected hip joint(s).

- Patient has a Harris Hip Score <70 in the affected hip

- Patient is willing and able to provide written informed consent.

- Patient is willing and able to cooperate in the required post-operative therapy.

- Patient is willing and able to complete scheduled follow-up evaluations as described
in the Informed Consent.

- Patient has participated in the Informed Consent process and has signed the Ethics
Committee approved informed consent.

Exclusion Criteria:

- The patient is:

- A prisoner

- Mentally incompetent or unable to understand what participation in the study
entails

- A known alcohol or drug abuser

- Anticipated to be non-compliant.

- The patient has a neuromuscular disorder, vascular disorder or other conditions that
could contribute to prosthesis instability, prosthesis fixation failure, or
complications in postoperative care.

- The patient has a neurologic condition in the ipsalateral or contralateral limb which
affects lower limb function.

- The patient has a diagnosed systemic disease that could affect his/her safety or the
study outcome.

- The patient is known to be pregnant.

- The patient is unwilling or unable to give consent, or to comply with the follow-up
program.

- The patient has received an investigational drug or device within the previous 6
months.

- The patient has an active or latent infection in or about the affected hip joint or an
infection distant from the hip joint that may spread to the hip hematogenously. The
patient has insufficient bone stock to fix the component. Insufficient bone stock
exists in the presence of metabolic bone disease (i.e. osteoporosis), cancer, and
radiation. Note: Dual Energy X-ray Absorptiometry (DEXA) may be used to assess the
presence of adequate bone stock.

- The patient has known local bone tumors and/or cysts in the operative hip.

- The patient has a known allergic reaction to one or more of the implanted material.

- The patient is Grade III obese with a Body Mass Index (BMI) ≥ 40.

- The patient has osteoradionecrosis in the affected hip joint

- Kidney insufficiency (Kidney insufficiency will be determined based on eGFR value.

See Blood Analysis Report CRF for details)