Anthropometric studies of the human sacrum relating to dorsal transsacral implant designs.

The sacrum offers several possibilities for fixation that, when combined, appear to provide a secure foundation for a dorsally-placed, transsacrally-fixed implant. The dorsal sacral landmarks, particularly the first and second dorsal foramina, are readily identifiable and relate in a consistent manner both qualitatively and quantitatively to the major mass of sacral bone, which is located ventrally to the vital structures of the sacrum. The authors have utilized these findings in the design of a new implant for direct sacral fixation.