Congenital vertebral malformations are common incidental findings in small breed dogs. This retrospective observational study evaluated the type and prevalence of thoracic vertebral malformations in 171 neurologically normal and 10 neurologically abnormal screw-tailed brachycephalic dogs. Neurologically normal dogs underwent CT for reasons unrelated to spinal disease, while affected dogs underwent MRI. Imaging studies were reviewed and vertebral malformations including hemivertebrae, block vertebrae, transitional vertebrae, and spina bifida were documented. The group of clinically normal dogs consisted of 62 French bulldogs, 68 Pugs and 41 English bulldogs. The group of affected dogs consisted of one French bulldog and nine Pugs. Overall, 80.7% of neurologically normal animals were affected by at least one vertebral malformation. There was a significant influence of breed, with thoracic vertebral malformations occurring more often in neurologically normal French bulldogs (P <0.0001) and English bulldogs (P = 0.002). Compared to other breeds, hemivertebrae occurred more often in neurologically normal French bulldogs (93.5%; P < 0.0001 vs. Pugs; P = 0.004 vs. English bulldogs) and less often in neurologically normal Pugs (17.6%; P = 0.004 vs. English bulldogs). Neurologically normal Pugs were more often diagnosed with transitional vertebrae and spina bifida compared to other breeds (P <0.0001 for both malformations). Of Pugs included in the study, 4.7% were diagnosed with clinically relevant thoracic vertebral malformations. When compared to the general veterinary hospital population, this was significantly more than the other two breeds (P = 0.006). This study indicates that thoracic vertebral malformations occur commonly in neurologically normal screw-tailed brachycephalic dogs. While hemivertebrae are often interpreted as incidental diagnostic findings, they appear to be of greater clinical importance in Pugs compared to other screw-tailed brachycephalic breeds.
Disc‐associated cervical spondylomyelopathy (DA‐CSM) is the most common cause of cervical spondylomyelopathy in dogs. In this condition, progressive caudal cervical spinal cord compression is typically caused by protrusion of one or more intervertebral discs. This disc‐associated compression is sometimes seen in combination with mild vertebral abnormalities and dorsal compression resulting from ligamentum flavum hypertrophy. The intervertebral disc space between the sixth (C6) and seventh (C7) cervical vertebrae is most commonly affected. Although several large breed dogs can be affected, the adult to older dobermann is overrepresented. Clinical signs vary from cervical hyperaesthesia to tetraplegia. Dogs can present with a chronic progressive or an acute onset of clinical signs. Many aspects of this multifactorial neurological syndrome are not completely understood and are the subject of controversy and debate. Although several factors have been proposed, the underlying pathology and aetiology remain unknown. Recently, new insights have been gained in the pathogenesis, diagnosis and treatment of this challenging neurological syndrome. This review outlines current controversies and new developments concerning the pathogenesis and diagnosis of DA‐CSM.
9 July 2016 in Journal of Feline Medicine and Surgery
Objectives: The objective was to evaluate the prevalence and possible breed predilections for thoracolumbar intervertebral disc disease (IVDD) in cats. Methods: Medical records and imaging studies of cats diagnosed with thoracolumbar IVDD between January 2008 and August 2014 were retrospectively reviewed and compared with the general hospital population. The association between type of IVDD (ie, intervertebral disc extrusion [IVDE] or intervertebral disc protrusion [IVDP]) and breed, age, sex, and duration and severity of clinical signs was also evaluated. Results: Of 12,900 cats presented during the study period, 31 (0.24%) were diagnosed with IVDD, including 17 purebred and 14 non-purebred cats. Of all presented purebred cats, 0.52% were diagnosed with thoracolumbar IVDD. More specifically, 1.29% of all British Shorthairs and 1.83% of all presented Persians were diagnosed with IVDD. Compared with the general hospital population, purebred cats ( P = 0.0001), British Shorthairs ( P <0.0001) and Persians ( P = 0.0006) were significantly overrepresented with thoracolumbar IVDD. Affected purebred cats were younger than affected non-purebred cats ( P = 0.02). Of 31 cats with IVDD, 19 were diagnosed with IVDE and 12 with IVDP. Cats with IVDE had a significantly shorter duration of clinical signs ( P = 0.0002) and demonstrated more severe neurological deficits ( P = 0.04) than cats with IVDP. Conclusions and relevance: Although thoracolumbar IVDD is an uncommon condition in cats, purebred cats, British Shorthairs and Persians, were overrepresented. It is currently unclear if this represents a true breed predisposition or a higher likelihood of owners of purebred cats seeking referral for advanced diagnostic imaging procedures.
28 June 2019 in Journal of Feline Medicine and Surgery
Objectives: The aim of this study was to evaluate if a combination of discrete clinical characteristics can be used to identify the most likely differential diagnoses in cats with spinal disease. Methods: Two hundred and twenty-one cats referred for further evaluation of spinal disease were included and categorised as follows: non-lymphoid neoplasia (n = 44); intervertebral disc disease (n = 42); fracture/luxation (n = 34); ischaemic myelopathy (n = 22); feline infectious peritonitis virus myelitis (n = 18); lymphoma (n = 16); thoracic vertebral canal stenosis (n = 11); acute non-compressive nucleus pulposus extrusion (n = 11); traumatic spinal cord contusion (n = 8); spinal arachnoid diverticula (n = 7); lumbosacral stenosis (n = 5); and spinal empyema (n = 3). Information retrieved from the medical records included signalment, clinical history and clinical presentation. Univariate analyses of variables (clinical history, breed, age, sex, general physical examination findings, onset, progression, spinal hyperaesthesia, asymmetry, ambulatory status and neuroanatomical location) were performed, and variables were retained in a multivariate logistic regression model if P <0.05. Results: Multivariate logistic regression revealed that intervertebral disc disease most often occurred in middle-aged, purebred cats with a normal general physical examination and an acute onset of painful and progressive clinical signs. Ischaemic myelopathy occurred most often in older cats with a stable or improving, non-painful, lateralising, C6–T2 myelopathy. Spinal fracture/luxation occurred most often in younger cats and resulted most often in a peracute onset, painful, non-ambulatory neurological status. Concurrent systemic abnormalities or abnormal findings detected on general physical examination were significantly associated with feline infectious peritonitis virus myelitis, spinal lymphoma or spinal empyema. Conclusions and relevance: This study suggests that using easily identifiable characteristics from the history and clinical examination can assist in obtaining a preliminary differential diagnosis when evaluating cats with spinal disease. This information could aid veterinary practitioners in clinical decision-making.
1 January 2018 in Veterinary Clinics of North America: Small Animal Practice
Acute herniation of nondegenerate nucleus pulposus material is an important and relative common cause of acute spinal cord dysfunction in dogs. Two types of herniation of nondegenerate or hydrated nucleus pulposus have been recognized: acute noncompressive nucleus pulposus extrusion (ANNPE) and acute compressive hydrated nucleus pulposus extrusion (HNPE). Spinal cord contusion plays an important role in the pathophysiology of both conditions. Sustained spinal cord compression is not present in ANNPE, whereas varying degrees of compression are present in HNPE. Although affected animals often present with severe neurologic signs, good outcomes can be achieved with appropriate treatment.