Annina Müller1,2, Franck Forterre2, Beatriz Vidondo3, Michael H Stoffel4, Ángel Hernández-Guerra5, Ioannis N Plessas6, Martin J Schmidt7, Christina Precht8. 1. Tierarztpraxis Emmevet AG, Hasle-Rüegsau, Switzerland. 2. Division of Small Animal Surgery, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland. 3. Department of Clinical Research and Veterinary Public Health, Veterinary Public Health Institute, Vetsuisse Faculty, University of Bern, Liebefeld, Switzerland. 4. Division of Veterinary Anatomy, Vetsuisse Faculty, University of Bern, Bern, Switzerland. 5. Department of Veterinary Medicine and Surgery, Universidad Cardenal Herrera-CEU, CEU Universities, Valencia, Spain. 6. Davies Veterinary Specialists Limited, Manor Farm Business Park, Higham Gobion, Herts, United Kingdom. 7. Clinic for Small Animals, Department of Veterinary Clinical Sciences, Justus-Liebig-University Giessen, Giessen, Germany. 8. Division of Clinical Radiology, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
Abstract
OBJECTIVE: The aim of this study was to evaluate differences in paraspinal musculature between dogs with and without atlantoaxial instability (AAI) using computed tomography scans. STUDY DESIGN: Retrospective multicentre study evaluating transverse reconstructed computed tomography scans of 83 small breed dogs (34 with and 49 without AAI) for the cross-sectional paraspinal musculature area at three levels (Occiput/C1, mid-C1, mid-C2). Ratio of moments, dorsal-to-ventral muscle-area ratios (d-v-ratio) and ratios of the dorsal and ventral musculature to C2 height (d-C2-ratio and v-C2-ratio) were evaluated for differences between groups using multivariate analysis of variance (p < 0.05) taking the head-neck position into account. RESULTS: Dogs with AAI showed a significantly lower d-v-ratio at levels 2 and 3, d-C2-ratio at level 2 and ratio of moments at all levels. When head-neck positions were analysed separately, ratio of moments was significantly lower in affected dogs at level 1 and 2. Also lower was d-C2-ratio at level 2, but only in flexed positioning. The head-neck position had a significant influence on ratio of moments and d-v-ratio at all three levels and on d-C2-ratio at level 1. CONCLUSION: Significant changes in muscle area were observed only for the hypaxial muscles at the C1 level, indicating a limited role of muscular adaption in AAI patients. Our results confirm an altered ratio of moments in dogs with AAI. The head-neck position has a significant impact and should be taken into account when evaluating spinal musculature. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).
OBJECTIVE: The aim of this study was to evaluate differences in paraspinal musculature between dogs with and without atlantoaxial instability (AAI) using computed tomography scans. STUDY DESIGN: Retrospective multicentre study evaluating transverse reconstructed computed tomography scans of 83 small breed dogs (34 with and 49 without AAI) for the cross-sectional paraspinal musculature area at three levels (Occiput/C1, mid-C1, mid-C2). Ratio of moments, dorsal-to-ventral muscle-area ratios (d-v-ratio) and ratios of the dorsal and ventral musculature to C2 height (d-C2-ratio and v-C2-ratio) were evaluated for differences between groups using multivariate analysis of variance (p < 0.05) taking the head-neck position into account. RESULTS: Dogs with AAI showed a significantly lower d-v-ratio at levels 2 and 3, d-C2-ratio at level 2 and ratio of moments at all levels. When head-neck positions were analysed separately, ratio of moments was significantly lower in affected dogs at level 1 and 2. Also lower was d-C2-ratio at level 2, but only in flexed positioning. The head-neck position had a significant influence on ratio of moments and d-v-ratio at all three levels and on d-C2-ratio at level 1. CONCLUSION: Significant changes in muscle area were observed only for the hypaxial muscles at the C1 level, indicating a limited role of muscular adaption in AAI patients. Our results confirm an altered ratio of moments in dogs with AAI. The head-neck position has a significant impact and should be taken into account when evaluating spinal musculature. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).
Authors: Andrew T Parry; Melissa M Upjohn; Katharina Schlegl; Sibylle Kneissl; Christopher R Lamb Journal: Vet Radiol Ultrasound Date: 2010 Nov-Dec Impact factor: 1.363
Authors: Assaf Lerer; Stephanie G Nykamp; Alexandra B Harriss; Thomas W G Gibson; Thomas G Koch; Stephen H M Brown Journal: Spine J Date: 2015-08-14 Impact factor: 4.166