[Total knee replacement with ceramic femoral components: a national prospective multicenter study of clinical and radiological outcomes].

Orthopädische Klinik und Poliklinik, Universität Rostock, Doberaner Straße 142, 18057, Rostock, Deutschland.
Der Orthopäde (Impact Factor: 0.36). 11/2010; 40(3):224-30.
Source: PubMed


The purpose of this prospective multicenter study was to evaluate the clinical and radiological outcomes of an unconstrained bicondylar total knee prosthesis with a new ceramic femoral component made of BIOLOX® delta.
Fifty patients underwent cemented total knee arthroplasty in three hospitals/centers. Clinical and radiological evaluations were undertaken preoperatively and at 3 as well as 12 months postoperatively using the HSS, WOMAC, and SF-36 scores.
During 12 months follow-up three patients had to undergo revision surgery due to non-implant-related reasons (infection, periprosthetic fracture, and retropatellar replacement). The mean preoperative HSS score amounted to 56.2±11.0 points. At 3 and 12 months follow-up the mean HSS score was 75.5±11.5 and 83.6±10.9 points, respectively. Therefore, HSS and WOMAC scores improved significantly from preoperative values at both postoperative evaluations. The first significant improvement of SF-36 score was seen after 12 months. Radiolucent lines around the femoral ceramic components were found in one case.
Subsequent long-term studies must be carried out in order to clarify the potential benefits of ceramic femoral components and confirm the good early clinical result. Moreover, the specific material properties of ceramic implants must be considered during implantation.

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    • "However, titanium materials that do not have a surface coating are not used for total knee replacement due to their comparatively low wear resistance [15]. Studies of ceramic knee components exhibited HSS scores of 86 points, with a range of motion of between 113° and 124° and a follow-up period of between one and ten years [14, 25, 28, 29]. However, ceramic implants are characterized by a higher risk of brittle fracture and the demand for cement-free implant fixation has not been realized so far, particularly in connection with polyvalent sensitization to cement components. "
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