Back to results
US 4,058,856 AGranted
Joint endoprosthesis
AssigneeSulzer Brothers Limited
InventorsErhard Doerre, Manfred Semlitsch, Otto Frey
Life of this patent
Estimating the term…
Abstract
The metal male joint part has a taper which is less than that of the cavity of the oxide ceramic female joint part. In addition, the surface of the male part has a resistance to deformation which is less than that of the core of the male part. The cone angle .beta. of the female cavity and the cone angle .alpha. of the male joint part are in the relation: tan .beta./2 - 0.001 .ltoreq. tan .alpha./2 .ltoreq. tan .beta./2 - 0.005.
Claims10
A joint endoprosthesis comprising
- a female joint part of oxide ceramic material having a cone-shaped cavity, said cavity having a taper of from 1:20 to 1:10;
- and
- a male joint part of metal material secured in said female joint part in self-locking relation, said male joint part having a core and a surface layer about said core disposed on a taper smaller than said taper of said cavity and having a resistance to deformation less than the resistance to deformation of said core.
A joint endoprosthesis comprising
- a female joint part of oxide ceramic material having a cone shaped cavity;
- and
- a male joint part of metal material secured in said female joint part in self-locking relation, said male joint part having a core and a surface layer about said core disposed on a taper smaller than said taper of said cavity and having a resistance to deformation less than the resistance to deformation of said core.
Dependencies are inferred from the claim text.