Inadvertent sacral bar transfixation of the cauda equina.

We present a case of inadvertent sacral bar transfixation of the cauda equina as a complication of posterior pelvic internal fixation. The "safe zone" for sacral bar placement is narrow, especially in the presence of fracture displacement. This complication can be avoided by achieving fracture reduction before internal fixation. Intraoperative fluoroscopy, including inlet and lateral sacral views, should be used in addition to tactile guidance to confirm the reduction. Even after prolonged compression, hardware removal under direct visualization can alleviate radicular symptoms with less effect on motor deficit.