Biomechanical comparison between standard and inclined screw orientation in dynamic hip screw side-plate fixation: The lift-off phenomenon.

ABSTRACT:

Background

Common failure modes of dynamic hip screw are cut-out and lift-off. To minimize the latter, distal screws can be inserted in different orientations. However, the effectiveness remains controversial. The aim of this study was to biomechanically investigate the influence of distal screw orientation on construct stability.

Methods

Thirty artificial generic long bones were assigned to three groups (n = 10) and fixed with two-hole dynamic hip screw-plates, inserting distal cortical screws with neutral parallel screw orientation (A), divergent screw orientation (B) or convergent screw orientation (C). Starting at 60 N, cyclic loading was applied to the implant tip perpendicular to the lag screw axis with progressive peak load increase at a rate of 0.002 N/cycle until fa

SUBMITTER: Zderic I 

PROVIDER: S-EPMC6718874 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature