Biomechanical comparison of plate-screw and screw fixation in medial tibial plateau fractures (Schatzker 4). A model study.

INTRODUCTION

The objective of this biomechanical study was to compare the respective efficiency of plate-screw fixation and screw fixation in an experimental model of a Schatzker type 4 fracture.

HYPOTHESIS

screw fixation and plate fixation have a similar load to failure.

MATERIALS AND METHODS

This study compares the stability of Schatzker type 4 medial tibial plateau fractures fixed with either 36.5mm cancellous bone screw with a 16 mm threaded segment or with six-holed buttress T-plate-screw system. A Schatzker type 4 fracture was modeled on an artificial bone model. In a first group of 10 fracture models, following the anatomical reduction, fractures were stabilized with screws with washers. In the second group, of 10 fracture models, fractures were stabilized with T-plate. After fixation ascending axial compression was applied on bone models (Instron machine).

RESULTS

Load bearing capacity was 1397.6+/-194.4N in the Group 1 and 2153.2+/-204.4N in the Group 2. The difference between the two groups was statistically significant (p<0.001).

DISCUSSION

According to this result, experimental load bearing of bone models indicate that plate-screw fixation system has a significantly higher stabilization capacity than fixation with three screws alone. Our hypothesis was not confirmed. In order to maintain anatomical repositioning, plate-screw system is a more stable fixation method than the screw in medial tibial plateau fractures Schatzker 4 LEVEL OF EVIDENCE: 1.