Alternative classification and screening protocol for transitional lumbosacral vertebra in German shepherd dogs

Acta Veterinaria Scandinavica

Anu K Lappalainen³  Reea Salomaa³  Jouni Junnila¹  Marjatta Snellman³  Outi Laitinen-Vapaavuori² 

[1] 4Pharma LTD, Turku, Finland

[2] Section of Small Animal Surgery, Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland

[3] Section of Diagnostic Imaging, Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland

关键词: German shepherd dog;    Dog;    Radiographic screening;    Lumbosacral transitional vertebra;   

Others  :  789473
DOI  :  10.1186/1751-0147-54-27

 received in 2012-01-24, accepted in 2012-05-01,  发布年份 2012

【 摘 要 】

Background

Lumbosacral transitional vertebra (LTV) is a common congenital and hereditary anomaly in many dog breeds. It predisposes to premature degeneration of the lumbosacral junction, and is a frequent cause of cauda equina syndrome, especially in German shepherd dogs. Ventrodorsal hip radiographs are most often used in diagnosis of LTV in screening programs. In this study, value of laterolateral lumbar spine radiographs as additions to ventrodorsal radiographs in diagnosis of LTV, and characteristics of LTV and the eighth lumbar vertebra (L8) in laterolateral radiographs were studied. Additionally, computed tomography (CT) features of different types of LTV were elucidated.

Methods

The ventrodorsal pelvic and laterolateral lumbar spine radiographs of 228 German shepherd dogs were evaluated for existence and type of LTV. Morphology of transverse processes was used in classification of LTV in ventrodorsal radiographs. The relative length of sixth (L6) and seventh (L7) vertebrae (L6/L7) was used in characterization of these vertebrae in laterolateral radiographs. CT studies were available for 16 dogs, and they were used for more detailed characterization of different types of LTV. Non-parametric χ² statistics, generalized logit model for multinomial data, and one-way analysis of variance was used for statistical analyses.

Results

In all, 92 (40%) dogs had a LTV, the most common type being separation of first spinous process from the median crest of the sacrum in 62 dogs (67% of LTV). Eight dogs had eight lumbar vertebrae. Those dogs with LTV had longer L7 in relation to L6 than dogs with normal lumbosacral junctions. When L6/L7 decreased by 0.1 units, the proportion of dogs belonging to the group with L8 was 14-fold higher than in the group with normal lumbosacral junctions. L8 resembled first sacral vertebra (S1) in length and position and was therefore classified as one type of LTV. With CT it was shown that categorizing LTV, based on shape and visibility of transverse processes seen in ventrodorsal radiographs, could be misleading.

Conclusions

We suggest that L8 be included as a part of the LTV complex, and the laterolateral radiographs of the lumbar spine be considered as an addition to ventrodorsal projections in the screening protocols for LTV.

【 授权许可】

   
2012 Lappalainen et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

Figure 3.

Figure 4.

Figure 5.

Figure 6.

Figure 7.

Figure 8.

Figure 9.

Figure 10.

Figure 11.

Figure 12.

Figure 13.

Figure 14.

【 参考文献 】

• [1]Evans HE: Miller's anatomy of the dog. 3rd edition. Saunders, Philadelphia; 1993.
• [2]Morgan JP, Bahr A, Franti CE, Bailey CS: Lumbosacral transitional vertebrae as a predisposing cause of cauda equina syndrome in German shepherd dogs: 161 cases (1987–1990). J Am Vet Med Assoc 1993, 202:1877-1882.
• [3]Morgan JP: Transitional lumbosacral vertebral anomaly in the dog: A radiographic study. J Small Anim Pract 1999, 40:167-172.
• [4]Flückiger MA, Damur-Djuric N, Hassig M, Morgan JP, Steffen F: A lumbosacral transitional vertebra in the dog predisposes to cauda equina syndrome. Vet Radiol Ultrasound 2006, 47:39-44.
• [5]Moore GE, Burkman KD, Carter MN, Peterson MR: Causes of death or reasons for euthanasia in military working dogs: 927 cases (1993–1996). J Am Vet Med Assoc 2001, 219:209-214.
• [6]Damur-Djuric N, Steffen F, Hassig M, Morgan JP, Flückiger MA: Lumbosacral transitional vertebrae in dogs: Classification, prevalence, and association with sacroiliac morphology. Vet Radiol Ultrasound 2006, 47:32-38.
• [7]Breit S, Knaus I, Kunzel W: Differentiation between lumbosacral transitional vertebrae, pseudolumbarisation, and lumbosacral osteophyte formation in ventrodorsal radiographs of the canine pelvis. Vet J 2003, 165:36-42.
• [8]Wigger A, Julier-Franz C, Tellhelm B, Kramer M: Lumbosakraler Übergangswirbel beim Deutschen Schäferhund: Häufigkeit, Formen, Genetik und Korrelation zur Hüftgelenksdysplasie. Tierärztl Prax 2009, 29(K):7-13.
• [9]Breit S, Kunzel W: The diameter of the vertebral canal in dogs in cases of lumbosacral transitional vertebrae or numerical vertebral variations. Anat Embryol (Berl) 2002, 205:125-133.
• [10]Larsen JS: Lumbosacral transitional vertebrae in the dog. J Am Vet Radiol Soc 1977, 18:76-79.
• [11]da Costa RC, Samii VF: Advanced imaging of the spine in small animals. Vet Clin North Am Small Anim Pract 2010, 40:765-790.
• [12]Radiographic Procedure for Hip Dysplasia Evaluation [http://www.fci.be/circulaires/46-2009-annex2-en.pdf] webcite
• [13]Flückiger M, Geissbühler U, Lang J: Lumbosakrale Übergangswirbel: Welche Bedeutung haben sie für die Gesundheit von betroffenen Hunden? Schweiz Arch Tierheilkd 2009, 151:133-135.