Patent ID: 7179296

Claim:
A provisional prosthesis for use during the trial fitting of a bipolar or unipolar joint prosthesis comprising: an outer provisional shell component having an exterior and an interior part-spherical bearing surface defining a polar axis, said interior surface having an open end with at least one recess extending from said open end and open to said interior surface, said exterior surface for rotating on a natural joint surface; an inner component having a part-spherical outer surface defining a polar axis and a conical bore for receiving a tapered trunnion on a hip implantor trial, said inner component outer surface polar axis capable of free angular articulation with respect to said outer shell part-spherical interior surface polar axis towards an equator of said outer component part-spherical interior surface to form a plurality of angles between the polar axes, said outer surface having at least one recess open to said outer surface which can be aligned with said at least one recess in said outer component; and a locking assembly having at least one pin for insertion into said aligned recesses in said inner and outer component for preventing said free angular articulation between said inner component polar axis with respect to said outer component polar axis.