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Intervertebral disc disease and aortic thromboembolism are the most common causes of acute paralysis in dogs and cats presenting to an emergency clinic

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Abstract

Background Acute paralysis is a common presentation in small animal emergency clinics, but the aetiological prevalence has not been reported. Knowledge of diagnosis frequency aids prioritisation of differential diagnoses, facilitates resource planning and clinical trial design. Methods Medical records from NC State Veterinary Hospital Emergency Room were searched over a five-year period to identify cases presenting with acute non-ambulatory paraparesis or paralysis. Signalment and diagnosis category were extracted. Results Acute paralysis was the presenting problem in 845 of 21,535 (3.9 per cent) dogs and 66 of 4589 (1.4 per cent) cats admitted over this period. Intervertebral disc disease (IVDD) was the most common cause (608 of 845; 72 per cent) in dogs, followed by vascular disease (34 of 845; 4.0 per cent). Other diagnostic categories accounted for the remaining 20 per cent. Dachshunds were the most common breed (263 of 845; 31.1 per cent), then Labrador retrievers (57 of 845; 6.7 per cent). In cats, aortic thromboembolism (ATE) was the most common diagnosis, occurring in 40 of 66 (60.6 per cent), followed by IVDD (7 of 66; 10.6 per cent). Other diagnostic categories accounted for 30.3 per cent. Six of 845 (0.7 per cent) dogs and two of 66 (3 per cent) cats were categorised as pseudoparalysis with a non-neurological diagnosis. Conclusions IVDD and ATE are the overwhelming causes of acute paralysis in dogs and cats, respectively, with approximately 28 per cent of dogs and 40 per cent of cats having a different diagnosis.

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... Historically most often referred to as Hansen Type I IVD disease, herniation or extrusion, this is the most common cause of spinal cord injury in dogs (113,114). Recently this type of herniation has widely been referred to simply as IVD extrusion, often with the prefix of "acute" applied to indicate the typical clinical presentation and to discriminate from more chronic manifestations of IVD extrusion. ...
... Embolization of fibrocartilage can affect the arterial and/or the venous sides of the circulation and results in a peracute onset of often dramatically lateralizing paresis or paralysis (98). The condition occurs most commonly in dogs, accounting for 2% of dogs presenting to an emergency clinic for non-ambulatory paraparesis or paraplegia (114), but it also occurs in a range of other species including the cat (95). ...
Article
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Intervertebral disc disease (IVDD) has been recognized in dogs since the 1800s, when the first descriptions of extruded disc material within the vertebral canal were published. In the intervening time our understanding of intervertebral disc pathology in dogs and cats has increased dramatically, with many variations of IVDD described. Whilst the volume of literature and collective understanding of IVDD has expanded, there has also been scope for confusion as the definition of intervertebral disc disease, with its myriad different manifestations, becomes more complicated. A large volume of literature has aimed to combine the use of histopathology, diagnostic imaging and clinical findings to better understand the various ways in which IVDD can be classified. Much of this research has focused on the classification of mechanisms of intervertebral disc degeneration, centering around the differences between, and overlaps in, IVDD in chondrodystrophic and non-chondrodystrophic dog breeds. However, with the increasing availability of advanced imaging modalities allowing more accurate antemortem diagnosis, the concept of IVDD has expanded to include other clinical presentations that may not fit into traditional models of classification of IVDD. This review aims to provide an up to date overview of both historical and current systems of IVDD classification, highlighting the important findings and controversies underpinning them.
... Intervertebral disc disease (IVDD) is the most common cause of acute paralysis in chondrodystrophic dogs presenting to small animal emergency clinics. 1 IVDD generally encompasses intervertebral disc extrusions (IVDEs) and protrusions. IVDEs can further be subclassified into five types, including the hydrated nucleus pulposus extrusion (HNPE). 2 HNPE mostly affects the cervical spine, with only four cases reported at T13-L1. ...
Article
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An 8-year-old female neutered Maltese Bichon Frise was presented to a small animal hospital for assessment of acute paraplegia. Diagnostic imaging including plain spinal radiographs and CT angiography was neither suggestive of an intervertebral disc extrusion nor any other abnormalities could be detected. The dog was referred to the emergency service of a specialty hospital for an MRI scan. The MRI showed features of a hydrated nucleus pulposus extrusion (HNPE) at L2-3. Subsequent hemilaminectomy identified a mixture of white gelatinous and partly firm material. Cytology and histol-ogy were consistent with a partially degenerated nucleus pulposus. Compressive HNPE of the lumbar spine was diagnosed. The dog was discharged 5 days postoperatively. At the last follow-up conducted by phone interview (2 months postoperatively), the owner reported normal ambulation without any signs of neurologic deficits.
... Afecções infecciosas como FeLV, FIV e criptococose foram descartadas por meio dos exames complementares realizados. A realização de mielografia permitiu descartar lesões expansivas ou compressivas dentro do canal medular, assim, as principais neoplasias medulares na espécie, como linfoma, meningioma e osteossarcoma foram excluídas como causa dos sinais neurológicos, bem como compressão medular por doença do disco intervertebral [16,17,20]. ...
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The cerebrospinal fluid (CSF) of healthy cats presents up to 5 cells/µL, with predominance of mononuclear cells and the presence of more than 1% eosinophils is rare and should always be considered an abnormal finding. There is no consensus on the term eosinophilic pleocytosis, as it is used to indicate the presence of more than 10 eosinophils/µL or more than 10% of the total leukocytes. The increase in eosinophils in the CSF may result from infectious, inflammatory, neoplastic and idiopathic diseases. The objective of this paper is to report a case of marked pleocytosis in CSF, with 84% eosinophils, probably due to toxoplasmosis, in a cat with paraparesis and diffuse spinal pain. A mixed breed female cat, neutered, adult and domiciled in a rural area was presented due to gait abnormalities in the pelvic limbs that started one day before presentation. The general physical examination was unremarkable. On neurological examination it was observed asymmetric deficit of postural reactions in pelvic limbs, patellar reflex normal to increased and pain elicited on palpation of the thoracic and lumbar spine. Based on these findings, the neurological syndrome was classified as thoracolumbar, but with diffuse pain, and the main differential diagnoses were inflammatory/ infectious and neoplastic diseases. The leukogram showed eosinophilia and the serum biochemistry showed no significant changes. Serological assays for feline immunodeficiency virus and feline leukemia virus were negative. Analysis of cerebrospinal fluid (CSF) identified marked pleocytosis with 84% eosinophils and increase in protein concentration. Myelography showed no compressive or expansive changes. Fungal culture for CSF cryptococcosis was negative. Serum immunofluorescence antibody titer for Toxoplasma gondii (IgG) was 1:256. There was a marked improvement after treatment with sulfametoxazole/trimethoprim and pyrimethamine and after 3 weeks of treatment, there was almost complete recovery of neurological signs and after 9 months the cat was neurologically normal. Discussion: The most common causes of acute-onset thoracolumbar spinal cord syndrome in cats, with diffuse pain on spinal palpation, are meningomyelitis of inflammatory/infectious origin, such as feline infectious peritonitis (FIP) and neoplasms such as lymphoma. Other meningomyelitis of inflammatory origin, such as infectious and immune-mediated meningomyelitis of unknown origin are considered uncommon in cats. Although the clinical, systemic and neurologi-cal signs of FIP and toxoplasmosis may have similarities, in the present case FIP was not considered responsible for the observed signs, as the evolution of the case and the analysis of the CSF tend to be different. The peripheral eosinophilia, the cytological analysis of the CSF, characterized by marked eosinophilic pleocytosis, associated with a positive titer for toxoplasmosis, good response to treatment and improvement in the neurological condition, with survival for more than 9 months after treatment, rules out the possibility of FIP. Neurological signs observed in the absence of systemic signs are more common in cases of protozoan reactivation, which probably occurred in the present case. The possibility of toxoplasmosis in the patient in this report was reinforced by the fact that the animal came from a rural area. Eosinophilia of CSF is most commonly associated with parasitic infections, although it can be caused by a variety of infectious agents, but in the cat of the present report, the marked eosinophilic pleocytosis was likely due to toxoplasmosis, which is a rare occurrence in this specie. In conclusion, toxoplasmosis should be considered in the differential diagnosis of focal spinal cord lesions in cats. The identification of laboratory findings as well as the appropriate therapy favored the good evolution of the condition.
... Thoracolumbar intervertebral disc extrusion (IVDE) is the most common cause of acute paralysis in dogs (Scott 1997, Ruddle et al. 2006, Aikawa et al. 2012, Rossi et al. 2020. Although there are currently no strict guidelines on which dogs should be treated medically or surgically, non-ambulatory dogs and dogs not responding to medical management are often treated surgically (Moore et al. 2016, Langerhuus & Miles 2017. ...
Article
Objectives Hydrotherapy is a common part of the postoperative care after surgical treatment of thoracolumbar intervertebral disc extrusion in dogs. There are currently no guidelines on when to commence hydrotherapy after surgery. Early hydrotherapy may be associated with an increased risk of postoperative complications including surgical site infection and neurological deterioration. The goal of this study was to report the prevalence and types of postoperative complications in dogs receiving early hydrotherapy. Materials and Methods Eighty-three dogs commencing hydrotherapy within 5 days after surgical treatment for thoracolumbar intervertebral disc extrusion were included in a retrospective descriptive study. All postoperative complications were recorded. Results Ten minor and 16 major complications were recorded in a total of 26 dogs. The majority of recorded complications were unlikely, but not excluded to be, caused by the initiation time of hydrotherapy. One dog developed a surgical site infection and one dog had a confirmed further extrusion of the originally operated intervertebral disc, which may have been influenced by early initiation of hydrotherapy. Clinical Significance Early hydrotherapy is possibly associated with occurrence of postoperative complications. Associations between the reported complications and early hydrotherapy, and possible benefits of early hydrotherapy, need to be further investigated before early initiation of hydrotherapy can be recommended.
... Hansen type I intervertebral disc extrusion (IVDE) is the most common spinal disorder and most common cause of acute paralysis in dogs , Rossi et al. 2020. This condition is characterised by chondroid degeneration predominantly affecting the nucleus pulposus, ultimately resulting in full thickness tears through the annulus fibrosus and acute extrusion of dehydrated and calcified nucleus pulposus into the vertebral canal (Hansen 1952, Smolders et al. 2013). ...
Article
Objectives To identify the prevalence of recurrence of clinical signs after initial successful decompressive surgery for intervertebral disc extrusion in French bulldogs. Materials and Methods A medical record search was performed to identify French bulldogs that experienced an initial successful outcome after surgery for thoracolumbar or cervical intervertebral disc extrusion. Collected information included signalment, neurological examination findings, intervertebral disc extrusion location, presence of vertebral malformations, kyphosis, type and extent of surgery. Decompressive surgery was not followed by extensive prophylactic fenestrations. Follow‐up information was retrieved from medical records and telephone interviews with referring veterinary surgeons. Results Eighty‐four French bulldogs with thoracolumbar (n=55) or cervical (n=29) intervertebral disc extrusion were included. Forty‐three (51%) dogs that had decompressive surgery for thoracolumbar (n=29) or cervical (n=14) intervertebral disc extrusion suffered recurrence of signs. The median time between decompressive surgery and recurrence of clinical signs was 9 months and 21 days. Of the 29 dogs suffering recurrence of clinical signs following surgery for thoracolumbar intervertebral disc extrusion, 24 returned for recurrence of clinical signs localised to the thoracolumbar segments, while five returned for recurrence of signs localised to the cervical region. Of the 14 dogs who suffered recurrence of signs following surgery for cervical intervertebral disc extrusion, nine returned for signs localised to the cervical region, while five returned for clinical signs localised to the thoracolumbar region. Clinical Significance This study suggests a high rate of late onset recurrence of clinical signs after decompressive surgery for intervertebral disc extrusion in French bulldogs. This information can aid in the management of owner expectations.
... Nearly 9% of all nonambulatory dogs with IVDE that present to our institution have DEEH; they are a small but important part of our emergency caseload. 13 Our perception was that these dogs did not have the same outcomes as dogs with TL-IVDE without DEEH. Researchers in several studies have found that body size impacts recovery, [14][15][16] and there is evidence that dogs with multilevel SCI have a worse prognosis compared with dogs with focal injury. ...
Article
Objective: To evaluate outcomes and prognostic factors after decompressive hemilaminectomy in paraplegic medium to large breed dogs with extensive epidural hemorrhage (DEEH) and thoracolumbar intervertebral disc extrusion (TL-IVDE). Study design: Retrospective, cohort, descriptive study. Animals: Fifty-nine client-owned dogs. Methods: Medical records and advanced imaging were reviewed for paraplegic dogs with DEEH. Ambulatory status 6 months after surgery and postoperative complications were recorded. Multiple logistic regression models were constructed to explore prognostic factors. Results: Records of 22 dogs with and 37 dogs without pelvic limb pain perception at presentation were included. Median age of dogs was 5 years (interquartile range, 4-7), and mean weight was 26.9 kg (SD, ±9.71). Labradors and Labrador mixes were most common (17/59 [28.8%]). Recovery of ambulation occurred in 17 of 22 (77.3%) dogs with and in 14 of 37 (37.8%) dogs without pain perception prior to surgery. Progressive myelomalacia was recorded in three of 59 (5.1%) dogs, one with pain perception and two without pain perception at presentation. Postoperative complications (14/59 [23.7%]) were common. Factors independently associated with outcome included clinical severity (odds ratio [OR] 0.179, P = .005), number of vertebrae with signal interruption in half Fourier single-shot turbo spin-echo sequences (HASTEi; OR, 0.738; P = .035), and ratio of vertebral sites decompressed to HASTEi (OR, 53.79; P = .03). Conclusion: Paraplegic medium to large breed dogs with DEEH have a less favorable outcome after surgical decompression than paraplegic dogs with TL-IVDE. Clinical significance: Dogs with DEEH can have severe postoperative complications. Loss of pain perception and increased HASTEi are associated with a poor outcome, while more extensive decompression improves outcome.
... Intervertebral disc disease (IVDD) is a common cause of acute spinal cord injury in dogs, due in large part to the high rates of early disc degeneration in chondrodystrophic breeds (1). Indeed, acute, severe thoracolumbar spinal cord injuries account for ∼4% of cases presenting to emergency rooms in North America, with 74% of these cases due to some form of IVDD (2) and ∼20,000 surgeries for the condition taking place annually (3). Paralysis is an extremely stressful clinical problem for pet owners, who have to process complex information on the underlying disease, the risks and costs of the procedures needed to diagnose and treat their pet, and the possibility that their pet might suffer permanent deficits or death. ...
Article
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Knowledge of the prognosis of acute spinal cord injury is critical to provide appropriate information for clients and make the best treatment choices. Acute intervertebral disc extrusions (IVDE) are a common cause of pain and paralysis in dogs with several types of IVDE occurring. Important prognostic considerations are recovery of ambulation, return of urinary and fecal continence, resolution of pain and, on the negative side, development of progressive myelomalacia. Initial injury severity affects prognosis as does type of IVDE, particularly when considering recovery of continence. Overall, loss of deep pain perception signals a worse outcome. When considering Hansen type 1 IVDE, the prognosis is altered by the choice of surgical vs. medical therapy. Concentration of structural proteins in the plasma, as well as inflammatory mediators, creatine kinase, and myelin basic protein in the cerebrospinal fluid (CSF) can provide additional prognostic information. Finally, cross-sectional area and length of T2 hyperintensity and loss of HASTE signal on MRI have been associated with outcome. Future developments in plasma and imaging biomarkers will assist in accurate prognostication and optimization of patient management.
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An 8‐year‐old female neutered Maltese Bichon Frise was presented to a small animal hospital for assessment of acute paraplegia. Diagnostic imaging including plain spinal radiographs and CT angiography was neither suggestive of an intervertebral disc extrusion nor any other abnormalities could be detected. The dog was referred to the emergency service of a specialty hospital for an MRI scan. The MRI showed features of a hydrated nucleus pulposus extrusion (HNPE) at L2‐3. Subsequent hemilaminectomy identified a mixture of white gelatinous and partly firm material. Cytology and histology were consistent with a partially degenerated nucleus pulposus. Compressive HNPE of the lumbar spine was diagnosed. The dog was discharged 5 days postoperatively. At the last follow‐up conducted by phone interview (2 months postoperatively), the owner reported normal ambulation without any signs of neurologic deficits.
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Background: Hydromyelia is a common magnetic resonance imaging (MRI) finding associated with compressive myelopathy caused by intervertebral disc extrusion (IVDE). Objectives: To describe the MRI features of hydromyelia and explore its relationship to clinical history, neurological severity, and the duration of cord compression. Animals: Ninety-one client-owned dogs with a focal compressive myelopathy secondary to thoracolumbar IVDE. Methods: A retrospective observational study was conducted in which MRIs were blindly evaluated to grade and localize hydromyelia and measure the degree of spinal cord compression. Duration and severity of clinical signs were recorded. Differences between hydromyelia grades in these variables were statistically assessed using a Wilcoxon and Kruskal Wallis test. Receiver operator curve analysis was used to determine the sensitivity and specificity for duration of clinical signs to predict the presence of hydromyelia. Results: Hydromyelia was identified at sites of IVDE in 84 of 91 dogs. An absence of hydromyelia was associated a with statistically longer duration of clinical signs (mean 73.1, IQR 76 days) when compared to cases with mild (mean 17.7, IQR 7.25 days, P = .006) or severe (mean 17.9, IQR 10.25 days, P = .006) hydromyelia. Duration of clinical signs <14 days was 78.6% sensitive and 85.7% specific for predicting the presence of hydromyelia. Conclusions and clinical importance: The MRI finding of hydromyelia might be a predictor of lesion chronicity in focal IVDE, helping to guide planning of hemilaminectomy surgery.
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A 4‐year‐old male neutered domestic shorthaired cat was presented for acute onset tetraplegia and respiratory signs. No pulses were palpable in any limb, and nociception was absent–all limbs were cold, and digital, metacarpal and metatarsal pads were cyanotic. Point‐of‐care ultrasound of the heart revealed severe left atrial enlargement, containing several large thrombi. Due to concerns for quality of life, euthanasia was elected. Postmortem findings revealed marked left atrial enlargement with thrombi filling the entire atrium, as well as emboli in both subclavian arteries and the abdominal aorta.
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Reports on intervertebral disc disease in cats are rare in the veterinary literature. It has been postulated that intervertebral disc protrusion is a frequent finding during necropsy in cats, without having any clinical relevance (King and Smith 1958, King & Smith 1960a, King & Smith 1960b). However, a total of six cases with disc protrusions and clinically significant neurological deficits have been reported over the past decade. (Heavner 1971, Seim & Nafe 1981, Gilmore 1983, Littlewood et al 1984, Sparkes & Skerry 1990, Bagley et al 1995). As in dogs, there are also two types of intervertebral disc disease in cats: Hansen's type I (extrusion), and type II (herniation). Cervical spinal cord involvement was more commonly recognised in cats than the lumbar or the thoraco lumbar area. Cats over 15 years were mainly affected (King & Smith 1958, King & Smith 1960a, King & Smith 1960b). We describe two cats with lumbar intervertebral disc protrusions. Emphasis is placed on differential diagnoses, treatment and follow-up.
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A retrospective review of records of 205 cats with histologically confirmed disease of the spinal cord was performed to identify the prevalence of disease in this nonrandomly selected population of cats. Clinical records were reviewed, and age, duration of neurologic illness, and clinical and histopathologic findings in cats with spinal cord disease were abstracted. Disease processes were classified into 7 categories and 23 groups. The most common diseases affecting the spinal cord of cats were feline infectious peritonitis (FIP), lymphosarcoma (LSA), and neoplasia of the vertebral column secondarily affecting the spinal cord. Information on age, onset and duration of clinical signs, and lesion localization at the postmortem examination in cats belonging to the 7 categories of disease were analyzed to create a practical list of differential diagnoses. Cats were also subcategorized into 3 groups based on their age at death. FIP was the most common disease of cats younger than 2 years of age. LSA and vertebral column neoplasia were the most common diseases affecting cats between 2 and 8 years of age. Vertebral column neoplasia was the most common disease affecting cats older than 8 years of age. Results of this histopathologic study showed that FIP and LSA were the most common disease processes affecting the spinal cord of cats. However, at least 21 other groups of diseases and their relative prevalence were identified.
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This retrospective study evaluated the magnetic resonance (mr) images of traumatic disc extrusions in 11 dogs. The findings included a reduction in the volume and signal intensity of the nucleus pulposus, focal hyperintensity within the overlying spinal cord on T (2)-weighted mr images, and subtle spinal cord compression, extraneous material or signal change within the vertebral canal. The largest area of hyperintensity in the spinal cord was directly over or close to the affected disc space, appeared asymmetrical and in the majority of cases was less than one vertebra in length. Parenchymal spinal cord haemorrhage was identified in four of the dogs. Vacuum phenomena, evident as a signal void in the centre of the disc, were identified in two of the dogs. The mr images were distinct from those reported for other causes of spinal cord dysfunction.