Metal Ion Release From an FDA-Approved Metal-on-Metal Total Hip Replacement Implant

Inclusion Criteria:

- Undergoing cementless primary total hip replacement

- Receiving acetabular cup of 52mm or greater

- Preoperative level of function and pain same as for conventional hip replacement

- Likelihood of obtaining relief of pain and improved function

- Full skeletal maturity

- Ability to follow instructions

- Good general health

- Willing to return for follow-up evaluations

- X-ray evaluation confirming the presence of NIDJD

- Femoral and acetabular bone stock that is sufficient, regarding strength and shape,
and suitable to receive the implants

Exclusion Criteria:

- Age less than 40 years or greater than 80 years at time of surgery

- Patients templated to receive an acetabular component smaller than 52mm in diameter

- Presence of a previous prosthetic hip replacement device in the hip joint to be
operated

- Previous girdlestone procedure or surgical fusion of the hip to be operated

- Acute femoral neck fracture

- Above knee amputation of the contralateral and/or ipsilateral leg

- Patients with a diagnosis of inflammatory degenerative arthritis

- Skeletally immature

- Evidence of active infections that may spread to other areas of the body

- The presence of a highly communicable disease that may limit follow-up

- Presence of known active metastatic or neoplastic disease

- Significant neurologic or musculoskeletal disorders or disease that may adversely
affect gait or weightbearing

- Any previous hip surgery or conditions that may interfere with the total hip
replacement's survival or outcome

- Any patient believed to be unwilling or unable to comply with a rehabilitation
program for a cementless total hip replacement or indicates difficulty to return for
follow-up

- Patient is know to be pregnant, a prisoner, mentally incompetent, and/or alcohol or
drug abuser

- Any patient who qualifies for inclusion in the study but refuses consent to
participate in the study

- Any steroid therapy, local or systemic, within three months prior to surgery

- Patient requiring structural bone grafts in order to support the prosthetic
components or to shape the bone to receive the implants

- Patient has known allergies to metal, e.g., jewelry

- Any patient not meeting all radiographic and clinical parameters for inclusion