Biomechanical properties of the atlantoaxial joint with naturally-occurring instability in a toy breed dog

F. Forterre; C. Precht; B. Riedinger; A. Bürki

doi:10.3415/VCOT-15-01-0005

Veterinary and Comparative Orthopaedics and Traumatology, Table of Contents

Vet Comp Orthop Traumatol 2015; 28(05): 355-358
DOI: 10.3415/VCOT-15-01-0005

Brief Communication

Schattauer GmbH

Biomechanical properties of the atlantoaxial joint with naturally-occurring instability in a toy breed dog

A comparative descriptive cadaveric study

F. Forterre

¹Division of Small Animal Surgery, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland

,

C. Precht

²Division of Radiology, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland

,

B. Riedinger

¹Division of Small Animal Surgery, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland

,

A. Bürki

³MEM Research Center, Institute for Surgical Technology and Biomechanics, University of Bern, Bern, Switzerland

› Author Affiliations

Abstract

Summary

The biomechanical properties of the atlanto-axial joint in a young Yorkshire Terrier dog with spontaneous atlantoaxial instability were compared to those of another young toy breed dog with a healthy atlantoaxial joint. The range-of-motion was increased in flexion and lateral bending in the unstable joint. In addition, lateral bending led to torsion and dorsal dislocation of the axis within the atlas. On gross examination, the dens ligaments were absent and a longitudinal tear of the tectorial membrane was observed. These findings suggest that both ventral and lateral flexion may lead to severe spinal cord compression, and that the tectorial membrane may play a protective role in some cases of atlantoaxial instability.

Keywords

Atlantoaxial instability - biomechanics - dog

Full Text

References

References
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