STANDARDIZED COMPARISON OF MECHANICAL STABILITY AND STIFFNESS FOR THE COTREL-DUBOUSSAT, HARRINGTON DISTRACTION, MOE AND LUQUE SPINAL FIXATION SYSTEMS.

The purpose of this study was to determine the relative stability and stiffness characteristics of various spinal fixation systems in accordance with standardized test procedures. The systems tested included the Cotrel-Duboussat (C-D), as well as the Luque (L), Harrington (H), Moe (M) with sublaminar wiring (1) and the unstable-uninstrumented spine (UU). Of special interest was the C-D system. All systems, except the C-D, were instrumented at the two levels (vertebral bodies) adjacent to (above and below) the instability site. The C-D was used as a single-level fixator on the geometric simulator and as both a single and double-level fixator on the bovine simulator.