Single cycle to failure in bending of three titanium polyaxial locking plates

Chadi Eid; Filippo Maria Martini; Andrea Bonardi; Filippo Lusetti; Anna Brandstetter de Belesini; Gianni Nicoletto

doi:10.3415/VCOT-16-07-0111

Veterinary and Comparative Orthopaedics and Traumatology, Table of Contents

Vet Comp Orthop Traumatol 2017; 30(03): 172-177
DOI: 10.3415/VCOT-16-07-0111

Original Research

Schattauer GmbH

Single cycle to failure in bending of three titanium polyaxial locking plates

Authors

Chadi Eid

¹Ortovet stp srl, Fidenza, Italy
Filippo Maria Martini

¹Ortovet stp srl, Fidenza, Italy

²University of Parma, School of Veterinary Medicine, Parma, Italy
Andrea Bonardi

¹Ortovet stp srl, Fidenza, Italy
Filippo Lusetti

¹Ortovet stp srl, Fidenza, Italy
Anna Brandstetter de Belesini

¹Ortovet stp srl, Fidenza, Italy
Gianni Nicoletto

³University of Parma, Department of Industrial Engineering, Parma, Italy

Abstract

Summary

Objective: Evaluation of the bending properties in one direction of three titanium polyaxial locking plate systems.

Materials and methods: The Polyaxial Advanced Locking System (PAX^®) straight plate (PAX SP), the PAX^® reconstruction plate (PAX RP), and the VetLOX reconstruction plates (VetLOX) were evaluated individually and as constructs applied to a bone model simulating a fracture gap and compared using a two-way analysis of variance and Tukey posthoc analysis.

Results: The PAX SP had the highest values of bending stiffness, bending structural stiffness and bending strength. When tested as plates alone, the PAX RP and VetLOX showed no differences with regard to bending stiffness and bending structural stiffness, whilst the PAX RP had significantly higher strength. The PAX RP construct had significantly higher bending stiffness, bending structural stiffness and bending strength than the VetLOX construct.

Clinical relevance: The PAX RP and VetLOX reconstruction plates are much more likely to fail when used as bridging implants, thus adjunct support is needed. The lower bending strength of the VetLOX reconstruction plates suggests it should not be used in fractures under high loads.

Keywords

Polyaxial - bone plate - locking plate - fourpoint bending - titanium

Full Text

References

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