An insert (20) is advanced and at least partially secured into a prosthetic device configured for use in a joint. The prosthetic device includes a shell (10) with a cavity defined by an interior surface (12, 14). The interior surface includes first (12) and second (14) portions that share an edge and that abut an edge (17B, 17B, 17C) of the interior surface (12, 14). The first portion (12) includes a partially spherical surface while the second portion (14) is a partially cylindrical shape. A maximum radius of the second portion is larger than a radius of the first portion. A center (I) defining the maximum radius of the second portion (14) is offset from a center (S) defining the radius of the first portion (12). The geometry of the interior surface (12, 14) allows the insert (20) to be advanced into the shell (10) in a single orientation. When advanced sufficiently into the shell (10), the insert (20) is rotated to constrain the insert (20) within the shell (10).
