Evaluation of the accuracy of a veterinary dynamometric wire tensioner

C. M. Gauthier; K. McGilvray; S. Myrick; F. Duerr; R. Palmer

doi:10.3415/VCOT-14-07-0111

Veterinary and Comparative Orthopaedics and Traumatology, Table of Contents

Vet Comp Orthop Traumatol 2015; 28(02): 104-108
DOI: 10.3415/VCOT-14-07-0111

Original Research

Schattauer GmbH

Evaluation of the accuracy of a veterinary dynamometric wire tensioner

Authors

C. M. Gauthier

¹Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
K. McGilvray

²Department of Mechanical Engineering, School of Biomedical Engineering, Colorado State University, Fort Collins, CO, USA
S. Myrick

³PetCare Veterinary Hospital, Santa Rosa, CA, USA
F. Duerr

¹Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
R. Palmer

¹Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA

Abstract

Summary

Objectives: The purpose of this study was to determine the accuracy of a commonly used veterinary wire tensioner.

Methods: Wire tension was measured using a load cell after each of five tensioners were used to tension each of six wires to the 66, 84, and 118 mm ring settings in an adjustable custom testing fixture. Each tensioner then experienced simulated aging and testing was repeated. Percentage error was calculated for each ring size, before and after tensioner aging. Measured tension values were compared to manufacturer reported tension values for each ring size using a one-sample two-way t-test; p <0.05 was considered significant.

Results: Compared to the manufacturer reported values, measured wire tension values were significantly lower for 66 mm and 84 mm rings and significantly higher for 118 mm rings, before and after simulated aging. Mean wire tension values did not significantly differ between individual wire tensioners.

Clinical significance: The tensioners tested achieved significantly different wire tension values than those reported by the manufacturer. This discrepancy could lead to under-tensioning and allowing excessive movement at a fracture site or over-tensioning, leading to wire breakage. We recommend tensioning wires at least to the recommended line on the device for 66 mm and 84 mm rings and at most to the recommended line for 118 mm rings. Further studies are needed to evaluate other veterinary wire tensioners and to develop a calibration method for these devices in practice.

Keywords

Wire tensioner - external skeletal fixator - biomechanics - tension

Full Text

References

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