Zielke instrumentation (VDS) for the correction of spinal curvature. Analysis of results in 66 patients.

Sixty-six patients who underwent anterior spinal fusion with Zielke instrumentation for thoracolumbar and lumbar curvatures were reviewed. Results compared favorably with reported series in which the Dwyer instrumentation system was used. The best corrections were obtained in the idiopathic single-curve group (45% correction of upper curve, 87% correction of lower curve, and 95% correction of instrumented curve) as compared with the double-curve group (33% correction of upper curve, 53% correction of lower curve, and 62% correction of instrumental curve). Vertebral body lateral translation (subluxation) was completely corrected in 87% of the patients. Instrumentation kyphosis can be prevented by placement of anterior wedge grafts in the intervertebral spaces. Complications were frequent but usually insignificant. The use of the Zielke instrumentation system offers the advantage of improved ability to derotate the spine while obtaining significant curve correction in a short fusion area.