Does Provisional Minifragment Fixation Prevent Compression With Dynamic Compression Plating? A Biomechanical Analysis.

OBJECTIVES:To compare the compressive force generated by a 3.5-mm compression plate with and without provisional fixation using a 2.0-mm minifragment plate. METHODS:Fourth generation composite large humeral sawbones underwent transection and were divided into 2 groups. The first group underwent fixation with a 3.5-mm compression plate; the second group underwent provisional fixation with a 2.0-mm plate followed by definitive fixation using a 3.5-mm plate. Using a load cell, the compressive force generated was measured after insertion of each of 2 eccentrical placed screws and the total compression recorded. RESULTS:There was no difference in the force generated after each successive compression screw (P = 0.59 and 0.58, respectively). Likewise, there was no significant difference in the total compression generated when the preload was accounted for (P = 0.93). CONCLUSION:Provisional minifragment fixation does not have any adverse effect on the forces generated during compression plating. These findings suggest that provisional minifragment plates do not need to be removed before definitive fixation.