[Bearing surfaces in primary hip arthroplasty. Is there any difference?]

Area of Science:

• Orthopedic Surgery
• Biomaterials Science
• Arthroplasty Research

Background:

• Primary hip replacement utilizes various bearing materials, with metal or ceramic heads paired with highly cross-linked polyethylene being most common.
• While these combinations yield good results, clinical superiority between ceramic-highly cross-linked polyethylene (CP) and metal-highly cross-linked polyethylene (MP) remains unclear.

Purpose of the Study:

• To systematically review literature and national arthroplasty registries to determine if clinically significant differences exist between CP and MP bearing surfaces in primary hip replacement.

Main Methods:

• A systematic review of literature and national arthroplasty registries was performed.
• Studies comparing CP and MP bearing surfaces with a minimum 10-year follow-up were analyzed for revision rates.

Main Results:

• The Australian registry indicated a difference in 15-year revision rates (CP: 6.3% vs. MP: 5.1%).
• The New Zealand registry found no significant difference in revision rates per 100 components per year (CP: 0.54 vs. MP: 0.61).
• No clinical studies meeting the inclusion criteria were identified.

Conclusions:

• Highly cross-linked polyethylene demonstrates a high survival rate in hip arthroplasty.
• Both ceramic and metal heads, when used with highly cross-linked polyethylene, show similar long-term clinical results.