BIOMECHANICAL ANALYSIS OF DORSAL PLATE FIXATION IN PROXIMAL PHALANGEAL FRACTURES

The biomechanical properties of three minifragment plate and screw sys tems were compared to determine whether plate systems primarily design ed for maxillofacial reconstruction are bio mechanically sound for use in proximal phalangeal fracture fixation. A middiaphyseal transverse osteotomy was created ir each of 30 fresh-frozen human proximal phalan ges to simulate an unstable fracture. Each osteotomy was then fixed wi th four 2.0ml screws through one of three different four-hole minifrag ment plates in a middorsal position. Plating systems tested included a vitallium plate with self-tapping screws (Luhr), a stainless steel pl ate with tapped screws (Synthes), and a titanium plate with tapped scr ews (Synthes). Testing was performed to failure in an apex volar three -point bending mode. The titanium-plated pha langes were the stiffest construct and required the greatest load and total energy absorbed to failure. However, only the load to failure for titanium versus stainle ss steel was significantly differ ent. Therefore, there is no biomecha nical disadvantage to using the titanium or vitallium plate and screw systems in the setting of unstable proximal phalangeal fractures.