Abstract
Aims: determine risk factors associated with component loosening so that measures can be implemented to improve component durability. Methods: The þrst 300 patients with Wright Medical Conserve Plusª metal-on-metal hip resurfacings were analyzed radiographically for radiolucencies and failed components were analyzed histologically after the components were sectioned. The group average age was 48 years, 75% were male, and most were operated for OA. At an average of 3 years, 7 hips required revision for femoral loosening, none for acetabular loosening. These included 4 of the þrst 100 cases, 1 in the 2nd 100, 2 in the 3rd 100. Radiographic lucencies were found in 9 of the 1st 100, and 3 in each of the of the 2nd and third 100. Results: The etiology of femoral loosening was found to be multifac-torial and risk factors included: substandard bone preparation, presence of large cysts or bone defects, cement technique, and patient activity.
The short metaphyseal stem serves as a useful Ç barometer È for þxation and impending loosening. Conclusions: Femoral loosening can be minimized by better patient selection and by excellent bone preparation and cement technique. Patients with compromised bone stock may still be successfully resurfaced if the extent of the defects is not excessive and/or the stem is cemented in.
Theses abstracts were prepared by Professor Dr. Frantz Langlais. Correspondence should be addressed to him at EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
