Strength of femoral neck fracture fixation. Comparison of six techniques in cadavers.

A neck osteotomy parallel to the femoral shaft was made on 36 cadaveric femora using the contralateral intact femur as a control. The osteotomies were fixed using a Thornton nail, two von Bahr screws, three Gouffon screws, three Knowles pins, a Haukebø compression screw, or an AO compression screw. The femora were then tested for bending strength using the load ratio test/control at 2- and 5-mm displacement as an expression of the relative strength of the osteosynthesis. There was no difference between the von Bahr, Haukebø, and the AO screws. These implants gave stronger fixation than the Thornton nail, Gouffon screws, and Knowles pins. The Thornton nail was stronger than three Gouffon screws or Knowles pins. The relatively stronger compression hip screws were thus not superior to two optimally placed 5-mm screws.