Short segment instrumentation for thoracolumbar fractures or fracture dislocations continues to be controversial. Recently, a load-sharing classification score was developed to help predict failure of posterior instrumented fusion alone used for highly comminuted and kyphotic fractures. Twenty-two patients treated with short-segment posterior instrumentation for thoracolumbar fractures were retrospectively reviewed. Although posterior instrumented fusion was used for fractures with a relatively high load sharing classification score, the load-sharing classification score was not predictive of posterior instrumentation failure. Single-level cephalad instrumentation failed at a higher rate than two-level cephalad instrumentation.
