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Outcome comparison in dogs with a presumptive diagnosis of thoracolumbar fibrocartilaginous embolic myelopathy and acute non-compressive nucleus pulposus extrusion
Abstract
Dogs with fibrocartilaginous embolic myelopathy (FCEM) or acute non-compressive nucleus pulposus extrusion (ANNPE) are reported to have a fair prognosis; however, persistent motor/autonomic deficits are possible. Specific MRI patterns have been suggested to differentiate these diseases although never been validated with histopathology in large studies. The aim of this retrospective study was to evaluate if these MRI patterns are associated with different clinical outcomes in dogs with peracute non-progressive T3-L3 myelopathy. Two hundred and one dogs were included. Outcome data were obtained via medical records and telephone questionnaires. MRIs were blindly reviewed by three board-certified observers, obtaining substantial to almost perfect interobserver agreement on diagnoses (κ=0.635–0.828). Presumptive ANNPE and FCEM were diagnosed in 157 and 44 dogs , respectively. Ambulatory function was regained in 99 per cent of cases, with persistent motor deficits in 83.6 per cent and 92.5 per cent of dogs with presumptive ANNPE and FCEM, respectively. The presumptive diagnosis was not associated with motor function recovery, recovery times or urinary continence. Faecal incontinence was five times more likely in dogs with presumptive ANNPE (23 per cent) compared with presumptive FCEM (7.5 per cent).
Distinguishing between MRI patterns of presumptive ANNPE or FCEM in dogs with peracute non-progressive T3-L3 myelopathy may help predict the risk of developing faecal incontinence.
... In the present study, variability was observed in the breed distribution, with the Labrador retriever showing 21% prevalence (7/33), which is in agreement with Freeman (2020) [4]. This could be because it is a large non-chondrodystrophic breed, which is an important feature that has been referred to by [22,35,37]. However, there was also an evident presence of small breeds, such as the Jack Russell terrier and Yorkshire terrier, as described by De Risio et al. (2009) [16]. ...
... The Portuguese water dog showed 9% (3/33) prevalence, as it is an autochthonous breed with a sample expression. Additionally, regarding sex, males were dominant in both groups, a finding that has been observed by other authors [2,16,22,24,50]. For the total sample population, the mean age was 6 years, and the mean weight was 24 kg, also similar to previous studies [11,16,22]. ...
... Additionally, regarding sex, males were dominant in both groups, a finding that has been observed by other authors [2,16,22,24,50]. For the total sample population, the mean age was 6 years, and the mean weight was 24 kg, also similar to previous studies [11,16,22]. ...
Acute noncompressive nucleus pulposus extrusion (ANNPE) is related to contusive spinal cord injuries, and dogs usually appear to be exercising vigorously at the time of onset. ANNPE has a characteristic peracute onset of clinical signs during exercise or following trauma, with non-progressive signs during the first 24 h and possibly signs of spinal shock. The main aim was to assess if the presence of spinal shock affects the neurorehabilitation outcomes of ANNPE dogs. This prospective controlled cohort clinical study was conducted at the Arrábida Rehabilitation Center. All of the dogs had T3-L3 injuries and were paraplegic/monoplegic with/without nociception, the study group (n = 14) included dogs with ANNPE spinal shock dogs, and the control group (n = 19) included ANNPE dogs without spinal shock. The study group was also evaluated using a new scale-the Spinal Shock Scale (SSS)-and both groups were under the same intensive neurorehabilitation protocol. Spinal shock was a negative factor for a successful outcome within less time. SSS scores > 4 required additional hospitalization days. The protocol was safe, tolerable, and feasible and accomplished 32% ambulation within 7 days, 29% in 14 days, and 29% in 30 days. The results were better than those obtained in previous studies-94% at 60 days-and 75% of the dogs without nociception recovered ambulation. Long-term follows-ups carried out 4 years later revealed a positive evolution.
... Traditionally, ANNPE and fibrocartilaginous embolism (FCE) have been considered as differential diagnoses because they commonly show decreased disc volume without distinct spinal cord compression on MRI [17]. Furthermore, they are clinically similar in that they both show an acute post-traumatic onset of clinical signs [14]. ...
... FCE has been differentiated from ANNPE on the basis of largely asymmetrical intramedullary lesions, including gray matter, with generally longer lesions than in cases with ANNPE [18]. Although ANNPE and IIVDE both involve extrusion of non-degenerative nucleus pulposus, our study has revealed some distinct MRI findings for IIVDE: longer hyperintense spinal lesion, more frequent parenchymal hemorrhage, and less contrast enhancement than previously reported for ANNPE patients [4,17]. We consider that among dogs presenting with IIVDE, intramedullary penetration or embedding of extruded disc materials causes severe parenchymal changes and more frequent hemorrhages than are observed among ANNPE patients. ...
... We consider that among dogs presenting with IIVDE, intramedullary penetration or embedding of extruded disc materials causes severe parenchymal changes and more frequent hemorrhages than are observed among ANNPE patients. Additionally, previous studies differentiate ANNPE and intradural extramedullary disc extrusion without a definitive distinction from IIVDE [13,15,17]. Because it is likely that some of the dogs diagnosed as ANNPE in previous reports were actually IIVDE, previously reported prognostic factors may differ from those suggested by our study. ...
Background:
Intradural-intramedullary intervertebral disc extrusion (IIVDE) is a rare condition of intervertebral disc disease. However, the diagnosis of IIVDE is challenging because the prognosis and imaging characteristics are poorly characterized.
Objectives:
We aimed to describe the clinical and imaging characteristics of tentatively diagnosed IIVDE in dogs to assess the prognostic utility of neurological grade and magnetic resonance imaging (MRI) findings.
Methods:
Twenty dogs were included in this retrospective cohort study.
Results:
Nonchondrodystrophic breeds (n = 16) were more predisposed than chondrodystrophic breeds. Most dogs showed acute onset of clinical signs. Neurological examination at admission showed predominant non-ambulatory paraparesis (n = 9); paresis (n = 16) was confirmed more frequently than paralysis (n = 4). Follow-up neurological examination results were only available for 11 dogs, ten of whom showed neurological improvement and 8 showed successful outcomes at 1 month. The characteristic MRI findings include thoracic vertebra (T)2 hyperintense, T1 hypointense, intramedullary linear tracts with reduced disc volume, and cleft of the annulus fibrosus. None of the MRI measurements were significantly correlated with neurological grade at admission. Neurological grade did not differ according to the presence of parenchymal hemorrhage, parenchymal contrast enhancement, and meningeal contrast enhancement. Neurological grades at admission showed a statistical correlation with those observed at the 1-month follow-up (r = 0.814, p = 0.02).
Conclusions:
IIVDE is a rare form of disc extrusion commonly experienced after physical activity or trauma and most frequently affects the cranial-cervical and thoracolumbar regions of nonchondrodystrophic dog breeds. Neurological score at admission emerged as a more useful prognostic indicator than MRI findings in dogs with suspected IIVDE.
... 9,10 Successful functional recovery, defined as recovery of unassisted ambulation and complete urinary and fecal continence, occurs in 66% to 81% of dogs with a MRI-or myelography-based diagnosis of ANNPE. 4,[11][12][13] However, in cases with unsuccessful outcome, this was mainly related to persistently impaired micturition or defecation rather than inability to walk unassisted. 4,[11][12][13] In a large study including 157 dogs with MRI consensus diagnosis of T3-L3 ANNPE 99% of cases recovered ambulatory function (although most often with a degree of persistent motor deficits), 92.5% were urinary continent and 77% were fecally continent at long-term follow-up. ...
... 4,[11][12][13] However, in cases with unsuccessful outcome, this was mainly related to persistently impaired micturition or defecation rather than inability to walk unassisted. 4,[11][12][13] In a large study including 157 dogs with MRI consensus diagnosis of T3-L3 ANNPE 99% of cases recovered ambulatory function (although most often with a degree of persistent motor deficits), 92.5% were urinary continent and 77% were fecally continent at long-term follow-up. 12 More specifically, fecal incontinence (FI) occurred in 100% of dogs that were paraplegic without nociception, 61% of dogs paraplegic with nociception, 20% of nonambulatory paraparetic or monoplegic dogs and in 9% of dogs that were ambulatory without assistance at the time of presentation. ...
... 4,[11][12][13] In a large study including 157 dogs with MRI consensus diagnosis of T3-L3 ANNPE 99% of cases recovered ambulatory function (although most often with a degree of persistent motor deficits), 92.5% were urinary continent and 77% were fecally continent at long-term follow-up. 12 More specifically, fecal incontinence (FI) occurred in 100% of dogs that were paraplegic without nociception, 61% of dogs paraplegic with nociception, 20% of nonambulatory paraparetic or monoplegic dogs and in 9% of dogs that were ambulatory without assistance at the time of presentation. 12 In humans with spinal cord injury (SCI), the level (cervical or thoracic compared to lumbar), duration (≥10 years compared to less), and severity of the lesion (complete compared to incomplete SCI) are predictors of the severity of neurogenic bowel dysfunction. ...
Background:
Urinary (UI) and fecal (FI) incontinence occur in up to 7.5% and 32% of dogs, respectively, after thoracolumbar acute noncompressive nucleus pulposus extrusion (ANNPE).
Hypotheses/objectives:
To investigate clinical, diagnostic, and therapeutic predictors of UI and FI in dogs with ANNPE affecting the T3-L3 spinal cord segments.
Animals:
Hundred and eighty-seven dogs with T3-L3 ANNPE diagnosed based on clinical and MRI findings.
Methods:
Multicenter retrospective study. Data were obtained from medical records and telephone questionnaires and analyzed by logistic regression.
Results:
UI and FI were reported in 17 (9.1%) and 44 (23.5%) dogs, respectively. Paraplegic dogs were 3 times (95% CI = 1.25, 10.87) more likely to develop UI (P = .018) and 4 times (95% CI = 1.94, 12.56) more likely to develop FI (P = .001) compared to nonparaplegic dogs. Dogs with an intramedullary hyperintensity greater than 40% of the cross-sectional area of the spinal cord at the same level on transverse T2-weighted MRI images were 4 times more likely to develop UI (95% CI = 1.04, 21.72; P = .045) and FI (95% CI = 1.56, 10.39; P = .004) compared to dogs with smaller lesions. FI was 3 times (95% CI = 1.41, 7.93) more likely in dogs that were not treated with nonsteroidal anti-inflammatory drugs (NSAIDs) after diagnosis compared to dogs administered NSAIDs (P = .006) and 2 times (95% CI = 1.12, 5.98) more likely in dogs presented with clinical signs compatible with spinal shock compared to dogs without (P = .026).
Conclusion and clinical importance:
The identification of clinical, diagnostic, and therapeutic predictors of UI and FI in dogs with T3-L3 ANNPE can help to approach these autonomic dysfunctions occurring after spinal cord injury.
... The prognosis for recovery of urinary continence in dogs with non-compressive T3-L3 spinal cord injury seems similar to those with a compressive injury, with 91-98% of dogs with hind limb dysfunction and present (intact) deep pain regaining urinary continence (24,40,41). However, interestingly, 15-23% of dogs remain faecally incontinent in the chronic phase of recovery (24,40,41), suggesting that the injury perhaps affects spinal cord tracts differently to acute "compressive" intervertebral disc herniation. ...
... The prognosis for recovery of urinary continence in dogs with non-compressive T3-L3 spinal cord injury seems similar to those with a compressive injury, with 91-98% of dogs with hind limb dysfunction and present (intact) deep pain regaining urinary continence (24,40,41). However, interestingly, 15-23% of dogs remain faecally incontinent in the chronic phase of recovery (24,40,41), suggesting that the injury perhaps affects spinal cord tracts differently to acute "compressive" intervertebral disc herniation. Indeed, contusive and vascular lesions induce more centrally located damage (as evident on MRI) than is induced by compressive intervertebral disc extrusion, likely affecting the descending inhibitory control of the defecation reflex. ...
Spinal cord injury in companion dogs can lead to urinary and fecal incontinence or retention, depending on the severity, and localization of the lesion along the canine nervous system. The bladder and gastrointestinal dysfunction caused by lesions of the autonomic system can be difficult to recognize, interpret and are easily overlooked. Nevertheless, it is crucial to maintain a high degree of awareness of the impact of micturition and defecation disturbances on the animal's condition, welfare and on the owner. The management of these disabilities is all the more challenging that the autonomic nervous system physiology is a complex topic. In this review, we propose to briefly remind the reader the physiology of micturition and defecation in dogs. We then present the bladder and gastrointestinal clinical signs associated with sacral lesions (i.e., the L7-S3 spinal cord segments and nerves) and supra-sacral lesions (i.e., cranial to the L7 spinal cord segment), largely in the context of intervertebral disc herniation. We summarize what is known about the natural recovery of urinary and fecal continence in dogs after spinal cord injury. In particular we review the incidence of urinary tract infection after injury. We finally explore the past and recent literature describing management of urinary and fecal dysfunction in the acute and chronic phase of spinal cord injury. This comprises medical therapies but importantly a number of surgical options, some known for decades such as sacral nerve stimulation, that might spark some interest in the field of spinal cord injury in companion dogs.
... This may reflect the study's sample size and population, but it could also be hypothesised that this region is less commonly affected by ischaemic disorders in dogs, such as fibrocartilaginous embolism, compared to other areas of the spinal cord. This is supported by the fact that fibrocartilaginous embolism has previously been reported to most commonly affect the T9 to L3 region in dogs (48). ...
The aim of the study was to describe the signalment, clinical presentation and presumptive or final diagnoses of dogs with cranial thoracic spinal cord lesions identified on advanced imaging.
Retrospective evaluation of the databases of three veterinary specialty centres, between 2009 and 2021, was performed to identify dogs with a lesion affecting the cranial thoracic vertebral column (T1-T6 vertebrae) as the primary cause for presenting signs of myelopathy and/or spinal pain.
Eighty-four dogs were included in the study, with the majority (n = 76) presenting with a progressive history of over four-weeks’ duration. On neurologic examination, most dogs were ambulatory (n = 64), and the most common neuroanatomic localisation was the T3-L3 spinal cord segments (n = 63). Twelve dogs (14%) showed a short-strided thoracic limb gait on clinical examination. The most common diagnosis was neoplasia (n = 33), followed by anomalies (n = 22, including vertebral body malformations in 14 dogs) and degenerative disorders (n = 16, with intervertebral disc protrusion diagnosed in 9 dogs). The most common vertebrae affected were T3 and T5. Most dogs with degenerative conditions showed asymmetric clinical signs, and the majority of dogs with neoplasia showed signs of spinal hyperaesthesia on examination.
The findings of this study describe the clinical signs and presumptive or final diagnoses associated with lesions affecting the cranial thoracic spinal cord. When combined with the signalment and clinical history, this information can assist in both the recognition of and problem-based approach to these cases.
... The characteristic clinical presentation of dogs and cats with ANNPE consists of a peracute onset of signs of myelopathy (ranging from paresis to plegia), usually occurring at strenuous exercise or related to external trauma (18,69,138). Clinical signs are lateralised in up to 90% of affected dogs, and are usually non-progressive after the first 24 h (18,69,77). ...
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.
... The clinical presentation of animals with ANNPE is almost identical to that of animals with ischemic myelopathy, which is most commonly caused by fibrocartilaginous embolic myelopathy. Differentiating between both conditions is important because there are indications that the long-term outcome, and especially the prevalence of fecal incontinence, might be different between dogs with ANNPE and ischemic myelopathy (155,156). Similar to ANNPE, specific MRI characteristics have been reported for ischemic myelopathy, which include a focal, relatively well-demarcated, possibly lateralized, longitudinal T2W hyperintense intramedullary lesion primary affecting the gray matter. The length of the lesion is usually longer than one vertebral body length (Figure 12) (157). ...
Imaging is integral in the diagnosis of canine intervertebral disc disease (IVDD) and in differentiating subtypes of intervertebral disc herniation (IVDH). These include intervertebral disc extrusion (IVDE), intervertebral disc protrusion (IVDP) and more recently recognized forms such as acute non-compressive nucleus pulposus extrusion (ANNPE), hydrated nucleus pulposus extrusion (HNPE), and intradural/intramedullary intervertebral disc extrusion (IIVDE). Many imaging techniques have been described in dogs with roles for survey radiographs, myelography, computed tomography (CT), and magnetic resonance imaging (MRI). Given how common IVDH is in dogs, a thorough understanding of the indications and limitations for each imaging modality to aid in diagnosis, treatment planning and prognosis is essential to successful case management. While radiographs can provide useful information, especially for identifying intervertebral disc degeneration or calcification, there are notable limitations. Myelography addresses some of the constraints of survey radiographs but has largely been supplanted by cross-sectional imaging. Computed tomography with or without myelography and MRI is currently utilized most widely and have become the focus of most contemporary studies on this subject. Novel advanced imaging applications are being explored in dogs but are not yet routinely performed in clinical patients. The following review will provide a comprehensive overview on common imaging modalities reported to aid in the diagnosis of IVDH including IVDE, IVDP, ANNPE, HNPE, and IIVDE. The review focuses primarily on canine IVDH due to its frequency and vast literature as opposed to feline IVDH.
... Extent and appearance are however variable and dependent on the degree of infarction. [5][6][7][8] The main differential for such a presentation is an acute non-compressive nucleus pulposus extrusion (ANNPE); however, meningomyelitis of unknown origin (MUO) and intramedullary neoplasia are often difficult to exclude based on imaging findings alone. Although neurological signs associated with fibrocartilaginous embolism (FCE) or ANNPE frequently improve over time with symptomatic care alone, severely affected patients (eg, with loss of nociception, urinary and faecal incontinence, or extensive lesions on MRI) often have a poor prognosis for neurological recovery. ...
A three-year-old Basset Griffon Vendeen was presented for peracute-onset paraplegia. MRI of the lumbar spinal cord confirmed marked intramedullary hyperintensity, and analysis of cerebrospinal fluid identified marked neutrophilic pleocytosis and increased protein concentration. An inflammatory aetiology was therefore considered possible despite imaging and history being more consistent with a diagnosis of fibrocartilaginous embolism (FCE). No neurological improvement occurred following appropriate treatment, and postmortem examination later confirmed numerous fibrocartilaginous emboli with marked, multifocal myelomalacia. This is the first case report to document marked cerebrospinal pleocytosis in a canine patient with FCE, and highlights that such changes should be interpreted with caution and not used to distinguish between vascular and inflammatory aetiologies.
In collaboration with the American College of Veterinary Pathologists.
Objective:
To compare the incidence of MRI lesions between dogs weighing < 15 kg (33 lb) and dogs weighing ≥ 15 kg.
Animals:
494 dogs with clinical signs of thoracolumbar disease.
Procedures:
Electronic medical records of affected dogs that underwent MRI of the thoracolumbar vertebral column between January 2016 and July 2018 were reviewed. Data extracted included age, body weight, breed, sex, MRI findings, and lesion location. Data were compared between dogs weighing < 15 kg and dogs weighing ≥ 15 kg.
Results:
Of dogs weighing < 15 kg, 94.4% (371/393) were chondrodystrophic breeds. Only 24.8% (25/101) of dogs weighing ≥ 15 kg were chondrodystrophic breeds. Lesions consistent with intervertebral disk disease (IVDD) had an overall incidence of 87.2% (431/494). In dogs weighing < 15 kg, the incidence of IVDD was 94.7% (372/393), compared with 58.4% (59/101) in dogs weighing ≥ 15 kg. Dogs weighing < 15 kg had a significantly higher incidence of IVDD lesions in the T12-13 segment, compared with dogs weighing ≥ 15 kg. Dogs weighing ≥ 15 kg were 11.9 times (95% CI, 5.1 to 27.9) and 7.4 times (95% CI, 2.3 to 23) as likely to have a neoplastic lesion and fibrocartilaginous embolic myelopathy, respectively, compared with dogs weighing < 15 kg.
Conclusions and clinical relevance:
IVDD was the most common MRI finding in the study population. Dogs weighing ≥ 15 kg had a higher incidence of nonintervertebral disk lesions, compared with dogs weighing < 15 kg.
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.
This chapter provides a logical approach to the diagnosis and treatment of the most common neurological presentations in general practice. It discusses neurologic syndromes such as epileptic seizures, movement disorders, altered mentation, blindness, abnormalities of pupil size, cranial nerve dysfunction, vestibular syndrome, cerebellar dysfunction, neck and/or spinal pain, proprioceptive ataxia, monoparesis and lameness, and neuromuscular weakness. Epileptic seizures represent one of most common neurological presentations in small animal general practice. Changes in mentation are common with neurological disease, and in some situations may be the only abnormality seen. The chapter provides a guide to the recognition, differential diagnosis, and approach to monoparesis in cats and dogs. It discusses various neuromuscular disorders including peripheral neuropathies, junctionopathies, and myopathies. A list of differential diagnoses for primary neuromuscular diseases is also provided.
Constrictive myelopathy has been described in pugs with paraparesis and is characterized by fibrous connective and granulation tissue within the dura mater causing spinal cord compression and focal gliosis. An association between constrictive myelopathy and caudal articular process (CAP) dysplasia is suspected; however, some studies have reported CAP dysplasia as an incidental finding. The imaging appearance of constrictive myelopathy is currently limited to a small number of cases. The aim of this multicenter, retrospective, descriptive study was to detail the magnetic resonance imaging (MRI) characteristics and to correlate these with clinical signs of presumptive constrictive myelopathy in pugs. Medical databases from five veterinary referral hospitals were reviewed to identify pugs with pelvic limb ataxia and paresis, that had a complete record of signalment, neurological examination, and MRI of the thoracolumbar spinal cord. The exclusion criteria were pugs with other conditions, such as unequivocal subarachnoid diverticula, hemivertebrae causing vertebral canal stenosis, intervertebral disc extrusions/protrusions, and multifocal/diffuse lesions. Twenty‐seven pugs met the inclusion criteria. All cases were ambulatory with paraparesis and ataxia. Nearly 60% were incontinent. Magnetic resonance imaging revealed a focal myelopathy in all cases showing one or more of the following lesions: CAP dysplasia (25/27), focal subarachnoid space irregular margination (26/27) with circumferential or dorsal contrast enhancement (10/12), and a symmetric V‐shaped ventral extradural lesion (23/27). This study describes specific MRI features of pugs with presumptive constrictive myelopathy, which authors hypothesize to be a consequence of chronic micro‐motion. Our results may help in diagnosing and subsequently treating this condition, which may warrant vertebral stabilization.
Background:
Recent studies have reported contrasting results of the effects of laser therapy on post-operative intervertebral disk herniation, with a lack of evidence-based advantages of this modality within a rehabilitation protocol. The aim of this study was to report the clinical effects of photobiomodulation therapy within a post-operative rehabilitation protocol in dogs submitted to surgery for thoracolumbar disk extrusion. Twenty-four dogs were included in the study (12 dogs treated with laser therapy and rehabilitation protocol and 12 dogs treated with same rehabilitation protocol but without laser therapy).
Results:
All dogs treated with laser therapy showed improved neurological status (Modified Frankel Score more than 3 within 30 days of physiotherapy starting) if deep nociception on admission was maintained (P = 0.04). However, Kaplan-Meier analysis did not show any statistical difference in time to regain ambulatory ability, although there was a tendency for a shorter mean time of 14.2 ± 8.55 days in the laser group versus 24 ± 18.49 days in the no laser group.
Conclusions:
The use of laser therapy in the post-operative rehabilitation of dogs affected by intervertebral disc extrusion and submitted to surgery for spinal decompression could help improve their neurological status.
Fibrocartilaginous embolic myelopathy (FCE) is common in dogs; however, there is conflicting
information in the veterinary literature regarding clinical characteristics and data on recovery
in severe cases is sparse. A systematic review of canine FCE was performed to delineate the
natural history of this disease. 322 previously reported cases and 71 previously unreported
cases were identified for inclusion. Source publications were identified via PubMed central
search and by references from review articles. Previously unreported cases were identified
via computerised medical records search at two veterinary institutions. FCE was most
common in middle-aged large breed dogs (30 per cent); however, the miniature schnauzer
was the most frequently reported individual breed and small breeds comprised 24 per cent
of all reported cases. The most common neuroanatomical localisation was a T3-L3
myelopathy (33.1 per cent). Prognosis for recovery of ambulation was good to excellent with
85 per cent of cases regaining the ability to walk unassisted, most within 3 weeks. Persistent
neurological deficits were common in patients that recovered ambulation (49.1 per cent).
When nociception was absent in the affected limbs at initial presentation, rate of recovery
was lower (10 per cent); however, this data is likely biased by limited follow-up in more
severe cases. Future prospective studies should evaluate prognosis for more severely affected
patients.
OBJECTIVE To evaluate interobserver agreement for features used in presumptive diagnosis of acute noncompressive nucleus pulposus extrusion (ANNPE) or ischemic myelopathy by MRI, compare findings on postcontrast T1-weighted (T1W) MRI sequences with fat saturation (FS) for the 2 conditions, and determine whether length and directional patterns of hyperintensity of the intramedullary spinal cord on T2-weighted (T2W) fast spin echo (FSE) MRI sequences differ between dogs with these diseases.
DESIGN Retrospective, observational study.
ANIMALS 20 dogs with clinical signs compatible with ANNPE (n = 14) or ischemic myelopathy (6).
PROCEDURES 3 observers evaluated MRI data (including T2W FSE, T2W single-shot FSE, and T1W FS sequences) for dogs with a presumptive diagnosis of ischemic myelopathy or ANNPE. Interobserver agreement for variables of interest including presumptive diagnosis was assessed by κ statistic calculations. Associations between diagnosis and variables of interest were assessed with Fisher exact or Cochran-Mantel-Haenszel tests.
RESULTS Perfect interobserver agreement (κ = 1 for all comparisons) was found for the presumptive diagnosis of ischemic myelopathy versus ANNPE. Meningeal enhancement on postcontrast T1W FS MRI images and nonlongitudinal directional pattern of intramedullary hyperintensity on T2W FSE images were significantly associated with a diagnosis of ANNPE. Greater length of intramedullary hyperintensity was significantly associated with a diagnosis of ischemic myelopathy.
CONCLUSIONS AND CLINICAL RELEVANCE Directional pattern and length of intramedullary hyperintensity on T2W FSE MRI images and enhancement patterns in postcontrast T1W FS sequences may provide important contributions to the criteria currently used in the presumptive diagnosis of ischemic myelopathy versus ANNPE.
This review discusses terminology, pathologic, clinical and magnetic resonance imaging findings, treatment, outcome and prognostic factors of fibrocartilaginous embolic myelopathy (FCEM), acute non-compressive nucleus pulposus extrusion (ANNPE) and intradural/ intramedullary intervertebral disc extrusion (IIVDE). FCEM, ANNPE, and IIVDE have a similar clinical presentation characterised by peracute onset of neurologic dysfunction that is generally non progressive after the initial 24-48 hours. Differentiating between these conditions can be challenging, however certain clinical and imaging findings can help. FCEM can occur in both adult and immature animals, whereas ANNPE or IIVDE have been reported only in animals older than 1 year. In dogs, ANNPE and IIVDE most commonly occur in the intervertebral disc spaces between T12 and L2, whereas FCEM has not such site predilection. In cats, FCEM occurs more frequently in the cervical spinal cord than in other locations. Data on cats with ANNPE and IIVDE is limited. Optimal magnetic resonance imaging (MRI) definition and experience in neuroimaging can help identify the findings that allow differentiation between FCEM, ANNPE, and IIVDE. In animals with ANNPE and IIVDE the affected intervertebral disc space is often narrowed and the focal area of intramedullary hyperintensity on T2-weighted images is located above the affected intervertebral disc
Ischemic myelopathy (IM) and acute noncompressive nucleus pulposus extrusion (ANNPE) are common spinal emergencies in dogs with similar clinical presentations. Magnetic resonance imaging (MRI) criteria for a presumptive antemortem diagnosis have been reported, however inter- and intraobserver agreement for use of these criteria has not been established. The aim of this retrospective, descriptive, cross-sectional study was to describe inter- and intraobserver agreement for using previously published MRI criteria to diagnose presumptive IM and ANNPE in a sample dogs. Dogs with a presumptive diagnosis of IM or ANNPE and available MRI scan data were retrieved from medical record archives during the period of 2009 and 2013. A total of 127 dogs were identified. From this sample, MRI scans for 60 dogs were randomly selected and duplicated for intraobserver analysis, giving a total of 187 anonymized studies that were presented to two blinded assessors (one board-certified veterinary neurologist, one board-certified veterinary radiologist). Assessors were asked to diagnose lesions as IM or ANNPE based on previously published MRI characteristics. Interobserver agreement in diagnosing IM or ANNPE was moderate (Kappa = 0.56) and intraobserver agreement was moderate to good (Assessor 1 Kappa = 0.79, Assessor 2 Kappa = 0.47). Agreement was strongest for detecting presence of lesions overlying a vertebral body (94% of lesions that were diagnosed as IM) or overlying an intervertebral disk (85% of lesions that were diagnosed as ANNPE). Findings indicated that use of previously published MRI criteria yields moderate inter- and moderate to good intraobserver agreement for a presumptive diagnosis of IM or ANNPE in dogs.
© 2015 American College of Veterinary Radiology.
Spinal cord injury (SCI) results not only in motor and sensory deficits but also in autonomic dysfunctions. The disruption of connections between higher brain centers and the spinal cord, or the impaired autonomic nervous system itself, manifests a broad range of autonomic abnormalities. This includes compromised cardiovascular, respiratory, urinary, gastrointestinal, thermoregulatory, and sexual activities. These disabilities evoke potentially life-threatening symptoms that severely interfere with the daily living of those with SCI. In particular, high thoracic or cervical SCI often causes disordered hemodynamics due to deregulated sympathetic outflow. Episodic hypertension associated with autonomic dysreflexia develops as a result of massive sympathetic discharge often triggered by unpleasant visceral or sensory stimuli below the injury level. In the pelvic floor, bladder and urethral dysfunctions are classified according to upper motor neuron versus lower motor neuron injuries; this is dependent on the level of lesion. Most impairments of the lower urinary tract manifest in two interrelated complications: bladder storage and emptying. Inadequate or excessive detrusor and sphincter functions as well as detrusor-sphincter dyssynergia are examples of micturition abnormalities stemming from SCI. Gastrointestinal motility disorders in spinal cord injured-individuals are comprised of gastric dilation, delayed gastric emptying, and diminished propulsive transit along the entire gastrointestinal tract. As a critical consequence of SCI, neurogenic bowel dysfunction exhibits constipation and/or incontinence. Thus, it is essential to recognize neural mechanisms and pathophysiology underlying various complications of autonomic dysfunctions after SCI. This overview provides both vital information for better understanding these disorders and guides to pursue novel therapeutic approaches to alleviate secondary complications.
Objective:
To determine the prevalence of spinal cord compression subsequent to traumatic intervertebral disk (IVD) extrusion in dogs, characterize factors associated with spinal cord compression in dogs with traumatic IVD extrusion, and evaluate the outcomes of dogs with traumatic IVD extrusion with or without spinal cord compression.
Design:
Retrospective case series.
Animals:
31 dogs with traumatic IVD extrusion.
Procedures:
Medical records and MRI findings were reviewed for dogs with a history of trauma to the spinal region. Dogs were included in the study if a neurologic examination and MRI were performed and there was a description of clinical signs and MRI findings including identification of the spinal cord segment affected by IVD extrusion, presence or absence of spinal cord compression, treatment, and outcome available for review.
Results:
31 of 50 (62%) dogs had traumatic IVD extrusions without any other detectable vertebral lesions; 9 (29%) and 22 (71%) of those 31 dogs did and did not have spinal cord compression, respectively. Dogs with spinal cord compression were significantly older and more likely to be chondrodystrophic and have evidence of generalized IVD degeneration, compared with dogs without spinal cord compression. The outcome for dogs with spinal cord compression was similar to that for dogs without spinal cord compression.
Conclusions and clinical relevance:
Results indicated traumatic IVD extrusion was common and should be considered as a differential diagnosis for dogs with trauma to the spinal region, and spinal cord compression should be evaluated, especially in older or chondrodystrophic dogs.
As the general population ages, the rising prevalence of vascular lesions of the spinal cord will become significant. The aim of this study was to compare the neurological and functional outcomes of patients with ischemic spinal cord injury (ISCI) and traumatic spinal cord injury (TSCI).
Spinal cord unit of a rehabilitation hospital in Italy.
Retrospective study.
We studied 179 patients with a TSCI and 68 with an ISCI. At admission and discharge, patients were examined by American Spinal Injury Association (ASIA) standards, Barthel Index, Rivermead Mobility Index and Walking Index for Spinal Cord Injury. Bowel and bladder management and discharge destination were recorded at discharge. Analysis of covariance (ANCOVA) and logistic regression models were used to analyze the effects of the etiology of the lesion, AIS level at admission, site of the lesion and the presence of complications on measured outcomes.
Patients with an ISCI were older and experienced fewer cervical lesions and complications at admission. By ANCOVA and logistic regression, age, AIS level and lesion level were the chief predictors of neurological and functional outcome, whereas etiology had no effect on outcome.
A diagnosis of ischemia and trauma is not a determinant of neurological and functional recovery in spinal cord injury patients. Instead, the outcome of these patients is influenced by age, lesion level and AIS level.
Retrospective cohort study.
To compare the neurological outcome between paraplegic patients with acute spinal cord ischaemia syndrome (ASCIS) or traumatic spinal cord injury (tSCI) and to investigate the influence of SCI aetiology on the total Spinal Cord Independence Measure (SCIM)-II score.
Level 1 trauma centre.
Initial (0-40 days) and chronic-phase (6-12 months) American Spinal Injury Association (ASIA) sensory scores, lower extremity motor score (LEMS) and chronic-phase total SCIM-II scores were analysed. Differences between ASCIS and tSCI patients were calculated using Student's t-tests and Wilcoxon signed-rank tests. To assess which variables give rise to the prediction of total SCIM-II score, a multiple linear regression analysis was used. These predictor variables included complete (ASIA impairment scale A) or incomplete SCI (AIS B, C, and D), aetiology, age and gender.
Out of 93 included patients, 20 ASCIS and 73 tSCI patients were identified. In the complete SCI group, the initial pinprick scores were higher (P<0.05) in ASCIS patients compared with tSCI patients, 37.9 (95% Confidence Interval (CI), 23.3-52.5) and 27.3 (95% CI, 24.1-30.4), respectively. No other relevant differences in neurological outcome were identified between ASCIS and tSCI patients; however, the total SCIM-II scores were higher (P<0.05) in tSCI patients after 12 months. Using the linear regression analysis, we were able to predict 31.4% of the variability. The aetiology was not significant in this model.
The neurological outcome was independent of the diagnosis ASCIS or tSCI. Furthermore, the diagnosis ASCIS or tSCI was not a significant predictor for total SCIM II scores after 12 months.
This study was granted by the 'Internationale Stiftung für Forschung in Paraplegie' (IFP), Zürich, Switzerland.
Experts opinions consensus.
To develop a common strategy to document remaining autonomic neurologic function following spinal cord injury (SCI).
The impact of a specific SCI on a person's neurologic function is generally described through use of the International Standards for the Neurological Classification of SCI. These standards document the remaining motor and sensory function that a person may have; however, they do not provide information about the status of a person's autonomic function.
Based on this deficiency, the American Spinal Injury Association (ASIA) and the International Spinal Cord Society (ISCoS) commissioned a group of international experts to develop a common strategy to document the remaining autonomic neurologic function.
Four subgroups were commissioned: bladder, bowel, sexual function and general autonomic function. On-line communication was followed by numerous face to face meetings. The information was then presented in a summary format at a course on Measurement in Spinal Cord Injury, held on June 24, 2006. Subsequent to this it was revised online by the committee members, posted on the websites of both ASIA and ISCoS for comment and re-revised through webcasts. Topics include an overview of autonomic anatomy, classification of cardiovascular, respiratory, sudomotor and thermoregulatory function, bladder, bowel and sexual function.
This document describes a new system to document the impact of SCI on autonomic function. Based upon current knowledge of the neuroanatomy of autonomic function this paper provides a framework with which to communicate the effects of specific spinal cord injuries on cardiovascular, broncho-pulmonary, sudomotor, bladder, bowel and sexual function.
Clinical features of 36 dogs with histologically confirmed fibrocartilaginous embolism (FCE) were contrasted with those of 26 dogs in which FCE was suspected based on characteristic clinical findings and the absence of compressive spinal cord disease on myelography. Dogs with confirmed and suspected FCE were of similar signalment, and had acute, nonprogressive dysfunction, often associated with trauma or exercise. The "suspected" group included fewer giant breeds and more often had asymmetric lesions, intact nociception, and upper motor neuron involvement. Dog size and severity of clinical signs probably contributed to owners choosing euthanasia in dogs with confirmed lesions. Accordingly, data from such patients may be skewed relative to these clinical features.
Literature review.
To present a comprehensive overview of autonomic assessment in experimental spinal cord injury (SCI).
A systematic literature review was conducted using PubMed to extract studies that incorporated functional motor, sensory or autonomic assessment after experimental SCI.
While the total number of studies assessing functional outcomes of experimental SCI increased dramatically over the past 27 years, studies with motor outcomes dramatically outnumber those with autonomic outcomes. Within the areas of autonomic dysfunction (cardiovascular, respiratory, gastrointestinal, lower urinary tract, sexual function and thermoregulation), not all aspects have been characterized to the same extent. Studies focusing on bladder and cardiovascular function greatly outnumber those on sexual function, gastrointestinal function and thermoregulation. This review addresses the disparity between well-established motor-sensory testing presently used in experimental animals and the lack of standardized autonomic testing following experimental SCI. Throughout the review, we provide information on the correlation between existing experimental and clinically used autonomic tests. Finally, the review contains a comprehensive set of tables and illustrations to guide the reader through the complexity of autonomic assessment and dysfunctions observed following SCI.
A wide variety of techniques exist to evaluate autonomic function in experimental animals with SCI. The incorporation of autonomic assessment as outcome measures in experiments testing treatments or interventions for SCI should be considered a high, clinically relevant priority.
Objective:
To differentiate between hydrated nucleus pulposus extrusion and ventral intraspinal discal cysts in dogs.
Study design:
Prospective case series.
Animals:
Twenty dogs with acute onset of cervical myelopathy due to hydrated nucleus pulposus extrusion or ventral intraspinal discal cysts.
Methods:
Clinical and magnetic resonance (MR) imaging findings, outcome after surgical treatment, cytologic and histologic findings of compressive material were taken into account. Comparisons and considerations were done between findings reported herein and what was previously described as suspected hydrated nucleus pulposus extrusion and intraspinal cysts.
Results:
All dogs were presented with acute onset of cervical myelopathy. MR imaging showed compressive cervical myelopathy at C2-C3 (n = 1), C3-C4 (n = 6), C4-C5 (n = 8), and C5-C6 (n = 5) intervertebral disc spaces, due to extradural material suggestive of either partially hydrated nucleus pulposus extrusion or intraspinal discal cyst, with T2 hyperintense and T1 iso-hypointense signal and variable contrast enhancement after gadolinium injection. All dogs were treated surgically by ventral slot (n = 15) or dorsolateral hemilaminectomy (n = 5). All dogs had a favorable outcome and regained a normal gait. The extradural material collected at surgery varied from liquid to more obvious gelatinous material. Cytologic or histologic examination of the material revealed similar findings for all dogs, compatible with partially degenerated nucleus pulposus.
Conclusions:
Dogs with acute onset of compressive cervical myelopathy due to extradural material resembling human intraspinal cysts on MR images are most likely to have extrusion of partially degenerated nucleus pulposus and should be treated accordingly.
Fibrocartilaginous embolic myelopathy (FCE) is common in dogs; however, there is conflicting information in the veterinary literature regarding clinical characteristics and data on recovery in severe cases is sparse. A systematic review of canine FCE was performed to delineate the natural history of this disease. 322 previously reported cases and 71 previously unreported cases were identified for inclusion. Source publications were identified via PubMed central search and by references from review articles. Previously unreported cases were identified via computerised medical records search at two veterinary institutions. FCE was most common in middle-aged large breed dogs (30 per cent); however, the miniature schnauzer was the most frequently reported individual breed and small breeds comprised 24 per cent of all reported cases. The most common neuroanatomical localisation was a T3-L3 myelopathy (33.1 per cent). Prognosis for recovery of ambulation was good to excellent with 85 per cent of cases regaining the ability to walk unassisted, most within 3 weeks. Persistent neurological deficits were common in patients that recovered ambulation (49.1 per cent). When nociception was absent in the affected limbs at initial presentation, rate of recovery was lower (10 per cent); however, this data is likely biased by limited follow-up in more severe cases. Future prospective studies should evaluate prognosis for more severely affected patients.
OBJECTIVE To compare clinical signs and outcomes between dogs with presumptive ischemic myelopathy and dogs with presumptive acute noncompressive nucleus pulposus extrusion (ANNPE).
DESIGN Retrospective study.
ANIMALS 51 dogs with ischemic myelopathy and 42 dogs with ANNPE examined at 1 referral hospital.
PROCEDURES Medical records and MRI sequences were reviewed for dogs with a presumptive antemortem diagnosis of ischemic myelopathy or ANNPE. Information regarding signalment, clinical signs at initial examination, and short-term outcome was retrospectively retrieved from patient records. Long-term outcome information was obtained by telephone communication with referring or primary-care veterinarians and owners.
RESULTS Compared with the hospital population, English Staffordshire Bull Terriers and Border Collies were overrepresented in the ischemic myelopathy and ANNPE groups, respectively. Dogs with ANNPE were significantly older at disease onset and were more likely to have a history of vocalization at onset of clinical signs, have spinal hyperesthesia during initial examination, have a lesion at C1-C5 spinal cord segments, and be ambulatory at hospital discharge, compared with dogs with ischemic myelopathy. Dogs with ischemic myelopathy were more likely to have a lesion at L4-S3 spinal cord segments and have long-term fecal incontinence, compared with dogs with ANNPE. However, long-term quality of life and outcome did not differ between dogs with ischemic myelopathy and dogs with ANNPE.
CONCLUSIONS AND CLINICAL RELEVANCE Results revealed differences in clinical signs at initial examination between dogs with ischemic myelopathy and dogs with ANNPE that may aid clinicians in differentiating the 2 conditions.
Most information about spinal arachnoid diverticula (SADs) in dogs has been retrieved from relatively small case series. The aim of this study was to describe this disease in a larger number of dogs.
Description of the signalment, clinical presentation, and imaging findings of a large number of dogs with SADs.
One hundred and twenty-two dogs with SADs.
Retrospective case series study. All medical records were searched for a diagnosis of SAD. The diagnosis was made based on myelography, computed tomography myelography (CT-m), or magnetic resonance imaging (MRI).
In the 122 dogs, 125 SADs were identified. Sixty-five were located in the cervical region and 60 in the thoracolumbar region. A higher body weight was significantly associated with a cervical localization of the SAD (P < .001). Ninety-five dogs were male and 27 dogs were female. Male dogs were significantly overrepresented (P < .0001). The most commonly affected breed was the Pug dog. Previous or concurrent spinal disorders, in the near proximity of the diagnosed SAD, were seen in 26 dogs. Eight of 13 French Bulldogs and 7 of 21 Pug dogs with SADs had a previous or concurrent spinal disease, whereas other spinal disorders occurred in only 1 of 17 Rottweilers with SADs.
Pug dogs and French Bulldogs might have a predisposition for SAD development. In a large percentage of these dogs, a concurrent spinal disorder, which might predispose to SAD formation, was diagnosed. The high prevalence in male dogs warrants further investigation.
Objective:
To determine the proportion of dogs with thoracolumbar intervertebral disk herniation (IVDH) that successfully recovered following hemilaminectomy and fenestration, the time to ambulation (TTA) in affected dogs after surgery, and the frequency of urinary and fecal incontinence in recovered dogs and to document long-term complications.
Design:
Retrospective case series.
Animals:
831 dogs with thoracolumbar IVDH treated by hemilaminectomy and concomitant disk fenestration by the same surgeon.
Procedures:
For all dogs, neurologic deficits before surgery had been assessed with a modified grading system. Dogs were reexamined after surgery over a period of 3 to 6 months, and follow-up evaluation was performed at > 12 months. The proportion of dogs that neurologically improved after surgery, TTA, and incidence of fecal or urinary incontinence in recovered dogs were compared among dogs with various grades of neurologic dysfunction before surgery.
Results:
Of 831 dogs, 122 had unsuccessful outcomes and 709 had successful outcomes. Of 620 dogs with intact deep nociception before surgery, 606 (97.7%) were ambulatory after surgery. Despite maintaining the ability to walk, 7 dogs were judged to have an unsuccessful outcome because the severity of ataxia did not improve. Of 211 paraplegic dogs with loss of deep nociception, 110 (52.1%) dogs became ambulatory after surgery. Long-term complications included incontinence, permanent neurologic deterioration, and self-mutilation. Dogs with paraplegia before surgery had a higher frequency of urinary or fecal incontinence, compared with dogs that were ambulatory.
Conclusions and clinical relevance:
Prognosis for dogs with thoracolumbar IVDH that retain deep nociception in at least 1 of the pelvic limbs or tail before surgery was good.
Fibrocartilaginous embolic myelopathy (FCEM) typically results in peracute onset of nonpainful, nonprogressive (after the first 24 hours), and often asymmetric neurologic deficits. Definitive diagnosis can be reached only through histologic examination of the affected spinal cord segments. Although MRI is the preferred diagnostic imaging modality for the antemortem diagnosis of FCEM, it may not show any changes in the first 24 to 72 hours of disease. Severity of neurologic signs at initial examination and extent of the lesions seen on MRI can help predict outcomes in dogs with FCEM.
Forty-eight dogs were diagnosed with presumptive exercise-associated peracute thoracolumbar disc extrusion. The median age was seven years (range two to 11 years), and median bodyweight was 23 kg (range 10 to 41 kg). The duration of signs before presentation ranged from 0.5 to four days. Twenty-nine dogs were non-ambulatory, of which 17 were incontinent and two had lost pain perception. Pelvic limbs were hyporeflexic or areflexic in 11 dogs. Intervertebral disc narrowing was evident on radiographs in 44 dogs. Myelography demonstrated a small, extradural space-occupying lesion dorsal to an intervertebral disc between T11-12 and L3-4 with adjacent spinal cord swelling. Forty-six dogs were treated non-surgically, one was euthanased and one was managed by hemilaminectomy (and subsequently euthanased). Follow-up information was available for 46 dogs 1.5 to 55 months after injury (median 22 months) showing that pelvic limb function had improved in all cases and all non-ambulatory dogs had regained the ability to walk. Six dogs remained faecally incontinent, and one dog remained urinarily and faecally incontinent.
Cross-sectional study.
To analyze the predictors of severe neurogenic bowel dysfunction (NBD) in persons with spinal cord injury (SCI).
The Kaohsiung Medical University Hospital, Taiwan.
Two questionnaires-the NBD score and the Beck Depression Inventory second edition-were sent to 232 persons with SCI by mail. The demographic factors and injury-related factors were recorded to evaluate any relationships with severe NBD. The associations between the severity of NBD and psychological condition were also measured.
In all, 39.4% of the respondents suffered from severe NBD. Multiple logistic regression analysis showed that those with a cervical injury (odds ratios (OR)=10.5, 95% confidence interval (CI) 1.6-67.7) or a thoracic injury (OR=7.1, 95% CI 1.2-40.3) had a higher risk of severe NBD than those with a lumbar injury. Persons with American Spinal Injury Association (ASIA) A had a 12.8-fold higher risk of severe NBD than persons with ASIA D (OR=12.8, 95% CI 3.3-50.1). Longer duration of injury (> or =10 years) was another risk factor of severe NBD. Moderate-to-severe depression was associated with reduced bowel function.
This study showed that high level of cord lesion, completeness of cord injury and longer duration of injury (> or =10 years) could predict the severity of NBD in patients with SCI.
Bowel dysfunction is a major problem in patients with spinal cord injury. Previous work has provided partial information, particularly about motor incomplete lesions. The purposes of this study were to evaluate the pathophysiologic features of neurogenic bowel in patients with motor incomplete spinal cord injury and to compare them with those in patients with motor complete lesions.
Fifty-four patients (59% men; mean age, 43 years) with chronic spinal cord injury and fecal incontinence and/or constipation were evaluated; 32 had motor incomplete lesions, and 22 had motor complete lesions. Clinical assessment, colonic transit time, and anorectal manometry were performed.
Colonic transit time was delayed similarly in patients with motor complete lesions and those with motor incomplete lesions. Anal squeeze pressure was present in most patients with motor incomplete lesions and absent in all patients with motor complete lesions. The cough-anal reflex was less frequent in patients with motor complete lesions with a neurologic level above T7 (P < 0.05). Rectal sensitivity was less severely impaired in those with motor incomplete lesions (P < 0.05). Most patients in both groups did not show anal relaxation during defecatory maneuvers. Rectal contractions and anal sphincter activity during distention of the rectum were detected more often in patients with motor complete lesions (P < 0.05).
Many severe pathophysiologic mechanisms are involved in neurogenic bowel, affecting patients with motor incomplete spinal cord injury similarly to those of patients with motor complete lesions with spinal sacral reflexes. The pathophysiologic mechanisms of constipation are obstructed defecation, weak abdominal muscles, impaired rectal sensation, and delayed colonic transit time; the mechanisms of fecal incontinence are impaired external anal sphincter contraction, uninhibited rectal contractions, and impaired rectal sensation. However, specific evaluation is required in individual cases.
Bowel dysfunction (e.g., fecal incontinence, infrequent or difficult defecation) are both frequent and severely troubling problems for patients with spinal cord injury, multiple sclerosis and Parkinson's disease. The etiology of these symptoms is complex; there may be autonomic and pelvic nerve dysfunction (with attenuation of voluntary motor function and impaired anorectal sensation and anorectal reflexes), or generalized systemic factors (e.g., altered diet and behavior, impaired mobility, psychological disturbances or drug adverse effects). The mainstay of current treatment is adapting a conservative approach towards reversing the systemic effects and optimizing the mechanics of defecation through the use of laxatives and irrigation approaches. When successful, this approach improves both evacuation and incontinence symptoms, with associated improvements in quality of life and independence. Future therapies may be directed at modulating pelvic innervation through electrical stimulation. Stoma formation remains an option for patients refractory to other approaches.
Fibrocartilaginous embolism (FCE) is a disorder of acute onset that presents with nonprogressive ataxia. We performed a retrospective examination of FCE of the spinal cord diagnosed by characteristic clinical findings and magnetic resonance imaging (MRI) in 26 dogs. In the present study, treatment consisting of physiotherapy alone, or this in combination with corticosteroid administration, was initiated immediately following diagnosis of FCE. Age at onset and the gender ratio in the present study closely correlated with those previously reported. In the present study, 88% of the dogs that developed FCE were small- to medium-sized, which is different from previously reported studies. There is a possibility that FCE also develops relatively frequently in small- to medium-sized dogs. No significant difference was observed between the physiotherapy alone and the physiotherapy and corticosteroids groups of dogs. FCE development has been reported predominantly at the vertebral levels C6-T2 and L4-S3 and less frequently at C1-5 and T3-L3. However, in the present study, FCE developed predominantly at T3-L3. FCE developed at T3-L3 or C1-5 in 69% of the cases in the present study, suggesting that there is relatively frequent development of FCE at these vertebral levels. The recovery time of T3-L3 was the shortest (10.2 +/- 7.4 days), and that of C1-5 was next-shortest (15.8 +/- 5.4) in this study. This suggested the possibility that the detection ratio of cases was low, because the symptoms in cases of FCE that has developed in C1-5 and T3-L3 would have improved before inspection in the secondary institution, where the MRI and diagnosis were performed.
To assess associations of severity of neurologic signs (neurologic score), involvement of an intumescence, and findings of magnetic resonance imaging (MRI) with interval to recovery and outcome in dogs with presumptive acute noncompressive nucleus pulposus extrusions.
Retrospective case series.
42 dogs with presumptive acute noncompressive nucleus pulposus extrusions.
Medical records and magnetic resonance (MR) images of dogs evaluated from 2000 through 2007 were reviewed. Inclusion criteria were acute onset of nonprogressive myelopathy following trauma or strenuous exercise, MRI of the spine performed within 7 days after onset, MRI findings consistent with acute noncompressive nucleus pulposus extrusions, and complete medical records and follow-up.
Clinical neuroanatomic localization of lesions was to the C1-C5 (n = 6), C6-T2 (6), T3-L3 (28), and L4-S3 (2) spinal cord segments. Median neurologic score was 3.5. Median duration of follow-up was 804 days (range, 3 to 2,134 days) after onset of neurologic signs. Outcome was successful in 28 (67%) dogs and unsuccessful in 14 (33%) dogs. Severity of neurologic signs, extent of the intramedullary hyperintensity on sagittal and transverse T2-weighted MR images, and detection of intramedullary hypointensity on GRE images were all associated with outcome on univariate analysis. Results of multivariate analysis suggested that maximal cross-sectional area of the intramedullary hyperintensity on transverse T2-weighted MR images was the best predictor of outcome.
Clinical and MRI findings can help predict outcome in dogs with acute noncompressive nucleus pulposus extrusions.
This paper presents a general statistical methodology for the analysis of multivariate categorical data arising from observer reliability studies. The procedure essentially involves the construction of functions of the observed proportions which are directed at the extent to which the observers agree among themselves and the construction of test statistics for hypotheses involving these functions. Tests for interobserver bias are presented in terms of first-order marginal homogeneity and measures of interobserver agreement are developed as generalized kappa-type statistics. These procedures are illustrated with a clinical diagnosis example from the epidemiological literature.
Fibrocartilage embolism originating from the intervertebral disk nucleus pulposus may induce acute spinal cord infarction. The main characteristics of this syndrome (acute, nonprogressive transverse myelopathy) are well known by the clinician. However, the impression that this disease is more commonly encountered in giant breeds of dogs, with intumescence involvement and loss of nociception may have been skewed relative to published data. A review of the vascularization peculiarities of the spinal cord explains the still hypothetical pathogenesis and helps to understand the diversity of the clinical presentation.
In large- and giant-breed dogs, fibrocartilaginous embolic myelopathy (FCEM) is a well-recognized syndrome of acute spinal cord infarction caused by embolization of fibrocartilage. The miniature schnauzer is reportedly the most frequently affected small breed, although clinical data from only six miniature schnauzers with FCEM is available in the literature. The purposes of this study were to determine the relative frequency of FCEM compared to other causes of myelopathy in miniature schnauzers, to characterize the clinicopathological features of FCEM in 38 miniature schnauzers, and to directly compare FCEM and intervertebral disk herniation in miniature schnauzers with respect to age at diagnosis; gender; neuroanatomical localization; and progression, asymmetry, and severity of neurological deficits. Fibrocartilaginous embolic myelopathy was the most common cause of myelopathy in miniature schnauzers. Age at diagnosis, asymmetry and severity of neurological deficits, and lack of progression of clinical signs after 24 hours assisted in distinguishing FCEM from intervertebral disk herniation. Fibrocartilaginous embolic myelopathy-related mortality in miniature schnauzers was significantly lower than mortality rates reported for affected large and giant breeds. Only 22% of miniature schnauzers were euthanized because of their disease, although the vast majority of survivors failed to achieve complete neurological recovery.
The records of 75 dogs with fibrocartilaginous embolism of the spinal cord were evaluated retrospectively. The diagnosis was confirmed histopathologically in 21 dogs (group A) and remained suspected in 54 patients (group B). The two groups were compared. Particular emphasis was placed on the description of physiotherapy procedures, recovery rates and prognostic criteria. Results demonstrated that fibrocartilaginous embolism affected mainly middle-aged, large- or giant-breed dogs. Clinical signs were peracute in onset, non-progressive and often asymmetric. Cerebrospinal fluid analysis was normal in the majority of dogs. Intramedullary swelling was the only abnormality detected on myelograms of these patients. A positive correlation was found between a poor prognosis and the involvement of intumescences, symmetrical clinical signs and decreased deep pain sensation. However, physio/hydrotherapy instituted immediately after the diagnostic work-up seemed to have a major influence on the recovery rate.
To determine long-term (> 6 months) outcome of dogs with paraplegia and loss of hind limb deep pain perception (DPP) resulting from intervertebral disk herniation or trauma.
Retrospective study.
87 dogs.
Outcome was determined as successful or unsuccessful. The association of neuroanatomic localization, breed, age, weight, sex, and (for dogs with intervertebral disk herniation) speed of onset of signs and duration of paraplegia prior to surgery with outcome was evaluated. Owners were contacted by telephone to identify long-term health problems.
Nine of 17 dogs with traumatic injuries were treated, and 2 regained the ability to walk; none of the 17 dogs regained DPP. Sixty-four of 70 dogs with intervertebral disk herniation underwent surgery; 9 (14%) were euthanatized within 3 weeks after surgery (7 because of ascending myelomalacia), 37 (58%) regained DPP and the ability to walk, 7 (11%) regained the ability to walk without regaining DPP, and 11 (17%) remained paraplegic without DPP. Outcome was not associated with any of the factors evaluated, but speed of recovery of ambulation was significantly associated with body weight and age. Fifteen (41%) and 12 (32%) dogs that regained DPP had intermittent fecal and urinary incontinence, respectively.
Results suggested that the prognosis for paraplegic dogs without DPP because of trauma was guarded, while dogs with disk herniation had a better chance of recovering motor function. A third of the dogs that recovered motor function had intermittent incontinence. Persistent loss of DPP did not preclude recovery of motor function, but such dogs remained incontinent.
Ischemia and infarction of the spinal cord is a known cause of acute spinal injury in dogs. Currently, the diagnosis of spinal cord infarction in small animals is based on history, clinical signs, and the exclusion of other differentials with radiography and myelography. It is a diagnosis only confirmed through necropsy examination of the spinal cord. The aim of this paper is to describe the Magnetic resonance imaging (MRI) findings of the spinal cord of dogs with suspected spinal cord infarcts to utilize this technology for antemortem support of this diagnosis. This retrospective study evaluated the spinal MR examinations of 11 dogs with acute onset of asymmetric nonpainful myelopathies. All patients except one (imaged at 2 months) were imaged within 1 week of clinical signs and managed conservatively with minimal medical and no surgical intervention. They were followed clinically for a minimum of 4 months after discharge. MR findings in all dogs were characterized by focal, intramedullary, hyperintense lesions on T2-weighted images with variable contrast enhancement similar to what is reported in humans. Though it could not be used to diagnose spinal cord infarction definitively, MRI was useful in excluding extramedullary spinal lesions and supporting intramedullary infarction as a cause of the acute neurologic signs. Together with the history and clinical examination findings, MRI is supportive of a diagnosis of spinal cord infarction.
Seven dogs with fecal incontinence and abnormal gaits were evaluated. Fecal incontinence was characterized as defecation of normal stools without posturing. Duration of clinical signs prior to evaluation ranged from 5 months to 3 years. Five dogs had upper motor neuron (UMN) paraparesis, and 2 dogs had UMN tetraparesis. With magnetic resonance imaging, spinal cord abnormalities primarily involving the dorsal aspect of the spinal cord were identified in all dogs. Five dogs had focal abnormalities, and 2 dogs had diffuse abnormalities of the spinal cord. Of the dogs with focal spinal cord lesions, 4 had cystic spinal cord abnormalities and 1 had a meningioma. Surgery was performed on all dogs with focal lesions; 4 of the 5 dogs had resolution of fecal incontinence after surgery. Results in these dogs suggest that fecal incontinence can be associated with spinal cord abnormalities and, depending on the characteristics of the lesion, can resolve after surgical treatment of the abnormality.
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.
The magnetic resonance imaging (MRI) features of ischemic myelopathy have been described in the human literature and in a small number of cases in the veterinary literature.
The aims of this study were to identify associations among MRI findings, timing of imaging, and presenting neurologic deficits in a large series of dogs with a presumptive diagnosis of ischemic myelopathy.
The medical records and MR images of dogs with a presumptive diagnosis of ischemic myelopathy (2000-2006) were reviewed retrospectively. Inclusion criteria were acute onset of nonprogressive and nonpainful myelopathy, 1.5-tesla MRI of the spine performed within 7 days of onset, and complete medical records and follow-up information. Presumptive diagnosis was based on history, as well as clinical, MRI, and cerebrospinal fluid (CSF) findings. The extent of the lesion on MRI was assessed as the following: (1) the ratio between the length of the hyperintense area on sagittal T2-weighted images and the length of C6 or L2 vertebral body, and (2) the maximal cross-sectional area of the hyperintense area on transverse T2-weighted images as a percentage of cross-sectional area of the spinal cord.
Fifty-two dogs met the inclusion criteria. MRI findings were abnormal in 41 dogs and normal in 11 dogs. The presence of MRI abnormalities was not significantly associated with the timing of imaging (P = .3) but was associated with ambulatory status on presentation (P = .04). Severity of signs on presentation was associated with extent of the lesion on MRI (P = .02).
The severity of signs on presentation is associated with the presence and the extent of the lesion on MRI.
To determine whether clinical signs or magnetic resonance imaging findings were associated with outcome in dogs with presumptive ischemic myelopathy.
Retrospective case series.
50 dogs.
Medical records and magnetic resonance images were reviewed. A neurologic score from 1 (normal) to 5 (most severe degree of dysfunction) was assigned on the basis of neurologic signs at the time of initial examination. Follow-up information was obtained from the medical records and by means of a telephone questionnaire completed by owners and referring veterinarians.
Median neurologic score at the time of initial examination was 3 (range, 2 to 5). Median follow-up time was 584 days (range, 4 to 2,090 days). Neurologic score at the time of initial examination and extent of the lesion seen on magnetic resonance images (quantified as the lesion length-to-vertebral length ratio and as the percentage cross-sectional area of the lesion) were significantly associated with outcome. Sensitivity of using a lesion length-to-vertebral length ratio > 2.0 or a percentage cross-sectional area of the lesion > or = 67% to predict an unsuccessful outcome was 100%.
Results suggested that severity of neurologic signs at the time of initial examination and extent of the lesions seen on magnetic resonance images were associated with outcome in dogs with ischemic myelopathy.
Fibrocartilaginous embolic myelopathy in miniature schnauzers Fibrocartilaginous embolism of the spinal cord diagnosed by characteristic clinical findings and magnetic resonance imaging in 26 dogs
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