Biomechanical comparison of wire osteosynthesis techniques in craniofacial surgery

The biomechanical stability of 20 different craniofacial wire osteosynthesis methods were tested in a simulated bone model. Utilizing wire fixation across a curved osteotomy site of an acrylic bar fixed at one end, compressive loading at the suspended end was used to test the resistance of the ligatures to stretch failure. Twenty-eight- and 30-gauge ligature patterns tested included single loops, double loops, and figure-eights across both 1- and 2-cm distances. A two-way analysis of variance was then used to determine the various effects of wire diameter, configuration, and loop length. The extensional deformation of ligature fixation was shown to be reduced by increasing the number of wire loops, reducing intraloop distances, or employing a slightly larger gauge diameter. The complex wiring configuration of a figure-eight technique was of no advantage over simple wire loops. In comparative strengths, two double loops were stronger than one double loop, and two single loops were stronger than one single loop or figure-eight. Comparable reductions in fixation strength were seen in all groups; there were larger intrabony distances between the burr holes or with the smaller gauge wire. These biomechanical ligature testing results are useful in those craniofacial skeletal sites where the use of more rigid fixation is either contraindicated or not desired.