Influence of the connecting rod on the biomechanical properties of five external skeletal fixation configurations

D. G. Bronson; J. D. Ross; J. P. Toombs; R. D. Welch

doi:10.1055/s-0038-1632764

Veterinary and Comparative Orthopaedics and Traumatology, Table of Contents

Vet Comp Orthop Traumatol 2003; 16(02): 82-87
DOI: 10.1055/s-0038-1632764

Original Research

Schattauer GmbH

Influence of the connecting rod on the biomechanical properties of five external skeletal fixation configurations

Authors

D. G. Bronson

¹Seay Center for Musculoskeletal Research, Texas Scottish Rite Hospital, Dallas, TX, USA
J. D. Ross

¹Seay Center for Musculoskeletal Research, Texas Scottish Rite Hospital, Dallas, TX, USA
J. P. Toombs

²Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Purdue University, West Lafayette, IN, USA
R. D. Welch

¹Seay Center for Musculoskeletal Research, Texas Scottish Rite Hospital, Dallas, TX, USA

Abstract

Summary

A recently developed external skeletal fixation system (SK™, IMEX Veterinary, Inc.) utilizes larger diameter connecting rods, therefore overcoming one of the weaknesses of the original Kirschner-Ehmer (KE) system. The purpose of the current study was to compare five typical external fixator constructs in axial compression, torsion, Cranial-Caudal (C-C) and Medial-Lateral (M-L) bending to determine the effect of the larger connecting rods on frame stiffness. The results demonstrate that the larger connecting rod has a significant effect on overall frame stiffness. The use of two or more full-pins, as in the type II and III techniques nullified the contribution of the connecting rod diameter and frame stiffness was more a factor of pin size, number and orientation.

Keywords

External fixation - biomechanics - Kirschner-Ehmer - SK™ - connecting rod

Full Text

References

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