Shell to be driven into a bone substance for a prosthetic joint

Abstract

A shell (1) for a prosthetic joint to be driven into a bone substance. The shell having an outer lateral surface (4) which is convexly curved in cross section and on which a plurality of ribs (5) is arranged. All ribs extend in the same direction at a preferably increasing gradient angle of 45° to 85° at the equatorial end (6) to a pole-side end (7). The cumulative flank projection area of all ribs (5) corresponds to at least a fifth of the entire outer lateral surface. As a result of this measure, a very high primary stability is achieved once the shell has been driven in, the shell being screwed into the bone substance very precisely and without bone material being sheared off. This arrangement can also be applied, similarly, to a concavely curved inner lateral surface.

Dependencies are inferred from the claim text.