A biomechanical comparison of 3.5 locking compression plate fixation to 3.5 limited contact dynamic compression plate fixation in a canine cadaveric distal humeral metaphyseal gap model

D. Filipowicz; O. Lanz; R. McLaughlin; S. Elder; S. Werre

doi:10.3415/VCOT-08-05-0042

Veterinary and Comparative Orthopaedics and Traumatology, Table of Contents

Vet Comp Orthop Traumatol 2009; 22(04): 1-8
DOI: 10.3415/VCOT-08-05-0042

Original Research

Schattauer GmbH

A biomechanical comparison of 3.5 locking compression plate fixation to 3.5 limited contact dynamic compression plate fixation in a canine cadaveric distal humeral metaphyseal gap model

D. Filipowicz

¹Department of Small Animal Clinical Sciences, Virginia Maryland Regional College of Veterinary Medicine, Virginia, USA

,

O. Lanz

² Department of Biomedical Sciences & Pathobiology, Virginia Maryland Regional College of Veterinary Medicine, Virginia, USA

,

R. McLaughlin

³ Department of Clinical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi, USA

,

S. Elder

⁴ Department of Agricultural and Biological Engineering, Mississippi State University, Mississippi, USA

,

S. Werre

⁴ Department of Agricultural and Biological Engineering, Mississippi State University, Mississippi, USA

› Author Affiliations

Abstract

Summary

3.5 locking compression plate (LCP) fixation was compared to 3.5 limited contact dynamic compression plate (LC-DCP) fixation in a canine cadaveric, distal humeral metaphyseal gap model. Thirty paired humeri from adult, large breed dogs were separated into equal groups based on testing: static compression, cyclic compression, and cyclic torsion. Humeral constructs stabilized with LCP were significantly stiffer than those plated with LCDCP when loaded in static axial compression (P = 0.0004). When cyclically loaded in axial compression, the LCP constructs were significantly less stiff than the LC-DCP constructs (P = 0.0029). Constructs plated with LCP were significantly less resistant to torsion over 500 cycles than those plated with LC-DCP (P<0.0001). The increased stiffness of LCP constructs in monotonic loading compared to constructs stabilised with non-locking plates may be attributed to the stability afforded by the plate-screw interface of locking plates. The LCP constructs demonstrated less stiffness in dynamic testing in this model, likely due to plate-bone offset secondary to non-anatomic contouring and occasional incomplete seating of the locking screws when using the torque-limiting screw driver. Resolution of these aspects of LCP application may help improve the stiffness of fixation in fractures modeled by the experimental set-up of this investigation.

Keywords

Fracture model - axial compression - cyclic torsion - LCP - LC-DCP

Full Text

References

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