Mechanical properties of 3M staples in bone block models.

The use of power driven staples is an accepted method of fixation for small bones of the hand and wrist and of the foot and ankle. The staples must be applied to flat or nearly flat surfaces. A synthetic model was developed to evaluate the ability of the 3M power driven staple system to resist failure due to pulling out of the staples in cantilever bending, tension, and torsion. Three different staple configurations and two leg lengths were evaluated in each of the test modes. Results indicated statistically significant differences between one and two staple configurations and between longer and shorter leg lengths. There was clear superiority of the two staple configurations and of longer leg lengths.