Arthrodesis of the ankle. A comparison of two versus three screw fixation in a crossed configuration.

Sixteen human anatomic specimen ankles underwent an arthrodesis using two (medial and lateral) or three (additional anterior) screw fixation. It was shown that significantly greater compression was achieved with three screws (p = 0.001). The order of screw fixation was important--better compression was achieved by inserting the lateral screw first. The resistance to torque was measured on a materials testing system, and the three screw fixation technique was significantly better (p = .001). The recommended fixation is one screw medially, one laterally, and one anterior from the tibia to the talus.