The influence of intramedullary fixation on figure-of-eight wiring for surgical neck fractures of the proximal humerus: a biomechanical comparison.

The resistance to torsional load was measured in a human cadaver model of a surgical neck fracture. Ten fresh-frozen human cadaver shoulders were thawed, dissected free of soft tissue attachments, and analyzed with dual energy x-ray absorptiometry to establish bone mineral density. Osteotomies were fixed with figure-of-eight wire alone and figure-of-eight wire supplemented with intramedullary Enders rods. Intramedullary Enders rods improved the mean maximum load by 1.5 times (p < 0.05). No statistically significant correlation was found between mean maximum load and bone mineral density.