Gertzbein and load sharing classifications for unstable thoracolumbar fractures.

From 1996 to 1998, 30 consecutive patients with Level 1 thoracolumbar spinal injury were classified and treated according to the Gertzbein classification and the load sharing classification. A posterior short segment pedicle screw implant was used in 21 patients; anterior decompression with strut grafting and application of the Kaneda device was used in three patients; and six patients were treated with short posterior instrumentation and an anterior strut graft. The average followup was 32 months (range, 24-50 months). The clinical outcome was satisfactory in 22 of 30 patients. Five of nine patients had neurologic improvement. Radiographic imaging findings showed a slight loss of reduction, but the clinical outcome of the patients was not affected. No pseudarthrosis and no implant failures were recorded. The Gertzbein classification correlates the type of fracture with the degree of mechanical instability and neurologic lesion. The load sharing classification correlates fracture comminution and displacement with mechanical stability and implant failure. Patient selection is a fundamental component for a successful outcome. The best candidates for surgery are cooperative patients who require spinal mobility, patients who are able to tolerate a two-stage reconstruction, and patients in good general health.