Postoperative evaluation of transpedicular screws with computed tomography.

The accuracy of screw placement was assessed with postoperative computed tomography (CT) scans in 75 consecutive patients treated with transpedicular screw fixation. The pedicular screws (n = 379) were inserted at levels ranging from thoracal (T-8) to sacral (S-2) vertebrae using different systems. Most of the screws (90%) were correctly placed in the pedicle. Ten screws (3%) were inserted medially into the spinal canal. Only 1 screw caused root compression symptoms. Screw misplacement lateral to the pedicle occurred in 18 cases (5%), 9 screws (2%) were inserted superior to the pedicle. No important complications developed that were related to the misplaced screws.