Conversion of high sacral to midsacral amputation via S-2 nerve preservation during partial S-2 sacrectomy for...

Chordomas of the sacrum require en bloc resection to reduce the risk of recurrence, but this may sacrifice nerves vital to bladder, bowel, and sexual function. High, mid-, and low sacral amputations have been previously classified based on nerve root sacrifice, not bony amputation. Sacrifice of the S-2 nerves or those above results in a high sacral amputation, but preserving the S-2 nerves converts it into a midsacral amputation. Preservation of the S-2 nerves has been shown to improve functional outcome, despite the bony osteotomy being unchanged. Thus, keeping the same bony amputation while preserving the S-2 nerve roots may allow for improved functional outcome while still achieving the same goal of oncological resection. Preservation of the S-2 nerves may be particularly difficult during amputation at the S-2 pedicle or above, and the authors describe their technique for preserving the S-2 nerves during partial sacrectomy at or just above the S-2 pedicle. Four cases of sacral chordoma resections are presented to illustrate the technique.