Abstract
Introduction
Metals used for total knee arthroplasty (TKA) are well known for their good biocompatibility, but may be a source of a release of metal ions that can be a cause of local and systemic adverse effects, aseptic loosening, and hypersensitivity reactions. One of the major difficulties in performing TKA is the selection of implants for patients who are preoperatively diagnosed as subject to metal sensitivity. Alternative solutions in cases of hypersensitivity are implants without metal constituents or metallic implants treated with a non-sensitive surface process. The aim of this study was to evaluate clinical results in patients who had been preoperatively diagnosed with metal sensitivity and who subsequently were provided with the zirconia-ceramic LFA-III TKA, and with a minimum 5-year follow-up.
Methods
Five patients (8 knees) with metal sensitivity underwent TKA using cemented zirconia-ceramic LFA-III implants. The LFA-III implant (KYOCERA Medical Co., Japan) is composed of a zirconia ceramic femoral component and a titanium-alloy tibial component with a polyethylene insert. All patients were female andthe average age at the time of surgery was 76.1 years. The average follow-up time was 7.2 years. Clinical and radiographic assessments were conducted with the Knee Society scoring system.
Results
No patients except one who had palmoplantar pustulosis preoperatively presented systemic or local dermatitis after surgery. The mean preoperative range of motion of 97.6 degrees improved to a mean of 110.7 degrees at the time of the most recent follow-up. The mean postoperative knee and function scores were 77.1 and 66.9, respectively. Subtle periprosthetic radiolucencies were found in 2 knees after the surgery.
Discussion
The zirconia-ceramic LFA-III TKA has performed well over a 5-year period in patients with metal hypersensitivity. Although this implant has a metal tibial component made of titanium, no systemic or local adverse events related to metal hypersensitivity were recorded. Ceramic implants can be an attractive alternative solution for patients suffering from hypersensitivity reactions to metals.
