A prosthesis assembly in one embodiment includes a stem configured to be implanted in a bone and including a first coupling portion, a head having a bearing surface configured to mate with at least one of a natural opposing joint component and a prosthetic opposing joint component, the head further having a second coupling portion, a coupler including a third coupling portion and a fourth coupling portion, the third coupling portion configured to couple with the second coupling portion, and an insert including (i) a fifth coupling portion configured to couple with the fourth coupling portion in any of a plurality of rotational orientations in combination with any of a plurality of roll angles and any of a plurality of pitch angles, and (ii) a sixth coupling portion configured to couple with the first coupling portion only when the insert assumes a predetermined rotational orientation with respect to the stem.