Abstract
Introduction: This prospective study focuses on the issue of a reliable prosthesis/bone fixation and compares the clinical and radiological outcome of the cemented and uncemented version of the prosthesis.
Methods: The prosthesis ensures congruent area contact with physiological kinematics resulting from imitation of the healthy morphology of the femoral condyle and unrestricted movement of the polyethylene bearing. From 1991 to 12/2007 we performed 624 medial implantations with cement (age 51–95, mean 71 years) and 185 cementless (age 40–84, mean 65 years). Other criteria as were similar. The follow up is (1.6–17) mean 9 years and seized 93% of the cases. They are assessed according to the KSRS and analyzed radiologically (F. C. Ewald).
Results: Knee Score (pre/post) cemented 41/93, cement-less 39/95. Function Score (pre/post) cemented 56/90, cementless 59/94. ROM increased for the cemented group Flex/Ex 107°/5° to 121°/2°, for the cementless Flex/Ex 107°/4° to 124°/1°.
Loosening needing revision: 15 times (2.5%) in the cemented group and 3 times (1.7%) in the cementless group. The survival rate (endpoint revision) is at 10 years: cemented 93.7%, cementless 94.5%.
The radiological investigation showed less radiolucent lines in the cementless cases in comparison to the cemented.
Conclusion: The prosthesis gives excellent results in the cemented and cementless application. The knee and function scores show similar improvements. The loosening rate of the cementless cases is even lower despite the higher physical demands of this 6 year younger group. The cementless fixation is attractive for younger patients and is pre-eminent for the mini-invasive implantation technique.
Correspondence should be addressed to: EFORT Central Office, Technoparkstrasse 1, CH – 8005 Zürich, Switzerland. Tel: +41 44 448 44 00; Email: office@efort.org
Author: Gustav Bontemps, Germany
E-mail: gustavbont@aol.com
