Lumbosacral foraminal ratios and areas using MRI in medium-sized dogs

D. Reynolds; R. L. Tucker; N. Fitzpatrick

doi:10.3415/VCOT-13-05-0085

Veterinary and Comparative Orthopaedics and Traumatology, Table of Contents

Vet Comp Orthop Traumatol 2014; 27(05): 333-338
DOI: 10.3415/VCOT-13-05-0085

Original Research

Schattauer GmbH

Lumbosacral foraminal ratios and areas using MRI in medium-sized dogs

Authors

D. Reynolds

¹Toronto Veterinary Emergency Hospital, Toronto, ON, Canada
R. L. Tucker

²Department of Veterinary Clinical Sciences, Washington State University, Pullman, WA, USA
N. Fitzpatrick

³Fitzpatrick Referrals, Surrey, United Kingdom

Abstract

Summary

Objective: To examine conventional magnetic resonance imaging planes of the lumbosacral foramina to obtain objective measurements of foraminal size in mediumsized (20–28 kg) normal dogs.

Method: Ten canine cadavers were evaluated using magnetic resonance imaging in neutral, flexed and extended position. Foraminal ratios, areas and lumbosacral angles were calculated and their relationship to body weight was evaluated.

Results: Foraminal ratios were found to be independent of body weight in medium sized dogs (p >0.42). Foraminal areas were dependent on body weight (p <0.05). Flexion and extension were shown to significantly change both the foraminal ratio and area.

Clinical significance: Lumbosacral foraminal stenosis is common in working dogs. Foraminal ratios were evaluated in mediumsized dogs and were found to be independent of body weight, which may provide objective evaluation of surgical decompression techniques if calculated pre- and post-surgery. Foraminal areas were not independent of body weight.

Keywords

Lumbosacral - foraminal stenosis - MRI - dogs

Full Text

References

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