Posterior transpedicular Zielke instrumentation of the lumbar spine.

Thirty-three patients treated by posterior transpedicular Zielke instrumentation of the lumbar spine were followed 1.1-2.7 years postoperatively. The average age of the patients was 64 years. The transpedicular technique allowed excellent fixation in patients with poor bone stock secondary to osteoporosis and extensive laminectomy defects. In particular, it allowed distraction and realignment of asymmetrically collapsed foramina with relief of pedicular kinking, correction of lateral deformity, and correction of reduced and fixed listhetic segments. Complications included one broken rod in the immediate postoperative interval while in the hospital. There was no late breakage of rods. The technique of transpedicular fixation with the ability to selectively distract or compress individual segments prevented any further collapse or displacement and allowed correction of areas of scoliotic collapse with relief of root entrapment. A normal lordosis was maintained as indicated by preoperative and postoperative measurements.