Internal Fixation of Femoral Neck Fractures in the Dog -an in vitro Study

N. E. Lambrechts; F. J.M. Verstraete; G. Sumner-Smith; A.D. Raath; M.J. van der Linde; H. T. Groeneveld

doi:10.1055/s-0038-1633056

Veterinary and Comparative Orthopaedics and Traumatology, Table of Contents

Vet Comp Orthop Traumatol 1993; 06(04): 188-193
DOI: 10.1055/s-0038-1633056

Original Research

Schattauer GmbH

Internal Fixation of Femoral Neck Fractures in the Dog -an in vitro Study

N. E. Lambrechts

¹Department of Surgery, South Africa

,

F. J.M. Verstraete

¹Department of Surgery, South Africa

,

G. Sumner-Smith

⁵Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Canada

,

A.D. Raath

²Department of Mechanical and Aeronautical Engineering, South Africa

,

M.J. van der Linde

³Department of Information Management, South Africa

,

H. T. Groeneveld

⁴Department of Statistics of the University of Pretoria, South Africa

› Author Affiliations

Abstract

Summary

The in vitro performances of four recognized fixation methods of femur neck fractures in the dog were evaluated. After a simulated basilar fracture, three multiple pin techniques and a lag screw method were applied to four groups of nine freshly dissected femurs. A standardized force was applied to all specimens as well as five intact femurs and the force-deformation curve and yield points were recorded. Radiographs were taken to determine the mode of failure. The results indicate that the lag screw and three-parallel-pin techniques were significantly stronger than the two-pin methods. The pin techniques failed by either bending and/or slippage, while the lag screw failed by bending and/or pulling in of the screw head into the lateral femoral cortex.

An in vitro study, comparing the mechanical performances of four fixation techniques for femoral neck fracture fixation, is presented. The lag screw and three-pin techniques were stronger than the two double-pin techniques. Fixation failure occurred through bending or slippage of the pins, or through bending of the screws or pulling of the screw head into the lateral femoral cortex.

Keywords

Dog - femoral neck - fracture - fixation - in vitro study

Full Text

References

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