Comparison of two fixation methods of oblique lesser metatarsal osteotomies: a biomechanical study

Two methods of internal fixation of oblique lesser metatarsal osteotomies were compared biomechanically using fresh-frozen human cadaver bones. Osteotomies were made obliquely through the metatarsal shafts and fixed with either crossed Kirschner wires or a single AO screw using the lag technique. The specimens were then fixed at their proximal end and loaded to failure using an axial torsion material testing system (MTS, Minneapolis, MN). Load displacement curves were obtained and the stiffness of the constructs were determined. Single-screw fixation was found to be significantly stiffer than the crossed wire configuration (P < .01). Single-screw fixation resulted in a stiffness of 211.2 +/- 111.7 N/cm (mean +/- SD), while stiffness of the crossed wire configuration averaged 56.9 +/- 25.1 N/cm.