A clinical Evaluation to determine metal ion release from 4th generation metal-on-metal hip articulating surfaces in cementless total hip arthroplasty.

This evaluation is being conducted to investigate the extent of metal ion release and its incorporation into the surrounding tissue resulting from metal on metal articulating surfaces in cementless total hip arthroplasty.

The amount of metallic ions released post operatively will be assessed by the concentration of Cobalt, Chromium and Molybdenum present in urine and analysed by I.C.P.M.S. (Inductive Coupled Plasma Mass Spectroscopy). The amounts of metallic ions released will be related to the hip function and range of motion measured pre-operatively and post-operatively. Secondary performance of the metal-on-metal articulation will be determined by radiographic evaluation and incidence of complications / revision rates.

Inclusion Criteria:

• Subjects selected for this Evaluation will be grouped by initial diagnosis into one of the following diagnostic groups:

  • Non-inflammatory degenerative joint disease including osteoarthritis, avascular necrosis and traumatic arthritis.
  • Rheumatoid arthritis.

• Selection of subjects for this Evaluation should include the following considerations:

  • Patients under 70 years of age.
  • Willing to return for follow-up evaluations.
  • No bias to sex.

Exclusion Criteria: