Metal sensitivity before and after total hip arthroplasty

Area of Science:

• Orthopedic Surgery
• Allergy and Immunology
• Biomaterials Science

Background:

• Metal sensitivity is a concern in patients undergoing orthopedic implant procedures.
• Total hip replacement (THR) involves materials like metal alloys and bone cement, potential allergens.

Purpose of the Study:

• To assess preoperative sensitivity to nickel, chromium, and cobalt in THR patients.
• To investigate the development of metal sensitivity after THR with metal-to-plastic prostheses.
• To evaluate sensitivity to bone cement in THR patients.

Main Methods:

• Preoperative patch testing for nickel, chromium, and cobalt sensitivity in 212 THR patients.
• Analysis of sensitivity in patients with previous implants (McKee-Farrar prosthesis).
• Monitoring for sensitivity development after implantation of metal-to-plastic prostheses.

Main Results:

• Fourteen out of 212 patients showed preoperative sensitivity to nickel, chromium, or cobalt.
• No sensitivity to bone cement was detected.
• 5.8% of patients with no prior metal implant history showed positive reactions.
• Two patients with failed McKee-Farrar prostheses were sensitive; none with stable prostheses were.
• Four patients developed sensitivity to nickel or cobalt after metal-to-plastic prosthesis implantation.

Conclusions:

• Preoperative metal sensitivity is present in a subset of THR candidates.
• Metal-to-plastic prostheses can potentially induce hypersensitivity.
• The clinical significance of pre-existing or induced metal hypersensitivity in THR patients is currently unknown.