A Novel Plate for Vertical Shear Fractures of the Medial Malleolus: A Biomechanical Study.

BACKGROUND

This study aimed to evaluate and compare stiffness and load to failure values of a novel medial malleolus compression plate (MP) and a 3.5-mm one-third tubular plate (TP) in the treatment of vertical shear fractures of the medial malleolus.

METHODS

Fourteen identical synthetic third-generation composite polyurethane bone models of the right distal tibia were randomly separated into two groups. Fracture models were created with a custom-made osteotomy guide to provide the same fracture characteristics in every sample (AO/OTA type 44A2). Fractures were reduced, and a novel MP was applied to bone models in the MP group and a TP was applied in the TP group. All of the samples were evaluated biomechanically, and force/displacement and load to failure values were recorded.

RESULTS

The force required to create displacement in the MP group was twice of that in the TP group. There was a significant difference between the two groups in all of the amounts of displacement (P = .006, P = .005, P = .007 and P = .015 for 0.5, 1.0, 1.5, and 2.0 mm, respectively).

CONCLUSIONS

In the treatment of vertical shear fractures of the medial malleolus, the strength of fixation with the novel MP is biomechanically higher than that with the one-third semi-TP.