Biomechanical comparison of two fixation methods for first metatarsophalangeal joint arthrodesis.

Abstract

The aim of this study was to compare the mechanical stability of two methods of fixation for arthrodesis of the hallux metatarsophalangeal joint: 1. a technique using an intramedullary screw and 2. a standard technique using crossed interfragmentary compression screws. The metatarsophalangeal joint was mechanically evaluated in cantilever bending using a servohydraulic testing machine. Differences in stiffness and strength parameters between the two techniques were checked for significance (P<0.05) using a paired t-test. Fixation provided by the intramedullary screw was stiffer and stronger than that from crossed compression screws. The stronger and stiffer intramedullary screw technique offers mechanical advantages over the crossed interfragmentary screw technique.