Recurrence rate of presumed thoracolumbar intervertebral disc disease in ambulatory dogs with spinal hyperpathia treated with anti-inflammatory drugs: 78 cases (1997–2000)

Objective: To determine the recurrence rate of clinical signs in dogs with spinal hyperpathia and mild neurological deficits due to presumed Hansen Type 1 thoracolumbar intervertebral disc disease (IVDD) that were managed medically with anti‐inflammatory agents, and to compare the recurrence rates between dogs treated with corticosteroids and those treated with nonsteroidal anti‐inflammatory drugs (NSAIDs). Design: Retrospective study. Setting: Private veterinary emergency clinic in a large metropolitan area. Animals, interventions, and measurements: Medical records were used to ascertain study eligibility, record patient signalment and condition severity, and document medical treatment regimen. Each dog was assigned a severity score: (1) spinal hyperpathia with no neurological deficits, (2) spinal hyperpathia with conscious proprioceptive deficits only, or (3) spinal hyperpathia with ataxia but still retaining ambulatory motor function. Owners of 78 dogs weighing less than 16 kg presented from 1997 through 2000 were sent a questionnaire to determine recurrence rate. Main results: All dogs recovered from the initial episode; 39 experienced recurrence and 39 did not. There was no statistically significant relationship between gender, age, or severity score and recurrence rate. Dogs treated with NSAIDs or methylprednisolone sodium succinate (MPSS) were less likely to experience recurrence than dogs treated with corticosteroids other than MPSS. Conclusion: A 50% recurrence of presumed IVDD occurred in this population of dogs after treatment with NSAIDs or corticosteroids. Those treated with NSAIDs or MPSS were less likely to experience a recurrence.     

The prevalence of subclinical gastroduodenal ulceration in Dachshunds with intervertebral disc prolapse

Endoscopy was used to determine the prevalence of subclinical gastroduodenal ulceration in 30 Dachshunds undergoing decompressive surgery for acute intervertebral disc prolapse. The endoscopy was performed on the day of admission and on the 3rd or 4th day after surgery. Three regions of the stomach (cardia, corpus and pylorus) and the proximal duodenum were visually inspected and biopsy samples were taken for histopathology. The combination of visual and microscopic changes were then used to determine the prevalence of subclinical gastroduodenal ulceration in this population. An overall prevalence of 76% was calculated from these findings. Ulcerogenic medication administered prior to admission did not appear to influence the prevalence. This result identifies a need for veterinarians to be aware of this potentially severe complication and warrants the use of prophylactic anti-ulcer medication in spinal surgery patients.     

Reoperative neurosurgery in dogs with thoracolumbar disc disease

OBJECTIVE: To characterize the subset of dogs in our neurosurgical practice that underwent spinal surgery for thoracolumbar (TL) disc herniation and subsequently underwent additional decompressive TL surgery. STUDY DESIGN: A retrospective case series. SAMPLE POPULATION: Thirty dogs that underwent reoperation for TL disc herniation. A comparison group of Dachshunds that underwent only one decompressive TL disc surgery was also studied. METHODS: Dogs that underwent reoperation were divided into two groups based on the interval between their first and second surgery. The early reoperation group included those dogs having a second surgery less than 4 weeks after the initial operation. The late reoperation group included those dogs having a second surgery more than 4 weeks after the initial operation. For each Dachshund in the late reoperation group, two Dachshunds that underwent only one decompressive TL disc surgery were selected and formed the comparison group. Dogs in the comparison group were matched with reoperated cases based on the severity of preoperative neurologic deficit and site of disc herniation. These two groups were compared to determine: (1) if age and body weight were risk factors for reoperation, and (2) if dogs had a poorer functional outcome after their second decompressive surgery than did those in the comparison group after their first (and only) decompressive surgery. RESULTS: A total of 30 of 467 (6.4%) dogs that underwent decompressive TL disc surgery were reoperated. In the early reoperative cases (n = 5 dogs), the inciting cause in all cases was residual compression from disc material at the site of the initial surgery. In the late reoperation group, 22 of 25 (88%) cases had a second disc herniation at a site distinct from the initial lesion. Dachshunds had a significantly higher risk for late reoperation (odds ratio and 95% CI = 3.67, 1.46 to 10.03); other small and medium-sized breeds (<20 kg) were underrepresented. Age and body weight were not significant predictors for reoperation. A total of 21 of 23 (91%) dogs had functional recovery after late reoperation. Complete sensorimotor loss was a significant negative predictor of functional recovery in the late reoperative cases (P = .01). Likelihood of functional recovery in dogs after their second decompressive surgery was identical to the functional recovery of dogs in the comparison group. CONCLUSIONS AND CLINICAL RELEVANCE: Our results show that a second disc herniation occurring at a site distinct from the initial lesion is the most common cause for reoperation and that Dachshunds have a significantly greater risk than other breeds.     

Influence of intervertebral disc fenestration at the herniation site in association with hemilaminectomy on recurrence in chondrodystrophic dogs with thoracolumbar disc disease: a prospective MRI study

Objective— To describe the influence of fenestration at the disc herniation site on recurrence in thoracolumbar disc disease of chondrodystrophoid dogs.
Study Design— Prospective clinical study.
Animals— Chondrodystrophic dogs (n=19).
Methods— Dogs were divided into 2 groups: group 1 (9 dogs) had thoracolumbar disc extrusion (Hansen type I) treated by hemilaminectomy and concomitant fenestration of the affected intervertebral disc and group 2 (10 dogs) had hemilaminectomy without fenestration. All dogs had 3 magnetic resonance imaging (MRI) examinations: preoperatively, immediately postoperatively to assess removal of herniated disc material, and again 6 weeks after surgery.
Results— There were 13 male and 6 female dogs; mean age, 7.1 years. Thoracolumbar disc herniation was confirmed with MRI. Immediate post surgical MRI revealed that the herniated disc removal was complete in all but 1 dog and that fenestration did not lead to complete removal of nucleus pulposus within the intervertebral disc space. On the 3rd MRI examination, none of the group 1 dogs had further disc material herniation at the fenestrated site. Six of the 10 group 2 dogs had a recurrence of herniation leading to clinical signs in 3 dogs (pain in 2 dogs, paresis in 1 dog).
Conclusion— In thoracolumbar disc herniation, fenestration of the affected intervertebral disc space prevents further extrusion of disc material.
Clinical Relevance— Fenestration reduces the risk of early recurrence of disc herniation and associated postoperative complications.     

THE RADIOLOGICAL DIAGNOSIS OF THORACOLUMBAR DISC DISEASE IN THE DACHSHUND

The accuracy of survey radiographs in the diagnosis of acute thoracolumbar disc disease in 36 Dachshunds was determined by comparison with lumbar myelographic findings using iohexol. The value of making radiographs immediately after injection of contrast medium and the effectiveness of oblique radiographs in determining the exact circumferential distribution of extruding or protruding disc material were assessed. The presence of a double contrast medium column, resistance to injection and the presence of cerebrospinal fluid flow during needle placement was also evaluated. The location of the affected disc was accurately determined on survey radiographs in only 26 dogs. The myelographic technique used in this study resulted in the correct intervertebral space being identified, together with the exact circumferential distribution of disc material, in 35 dogs. Survey radiographs alone are inadequate for localization of protruding or extruding disc material.     

Risk factors for recurrence of clinical signs associated with thoracolumbar intervertebral disk herniation in dogs: 229 cases (1994-2000)

OBJECTIVE: To assess risk factors for recurrence of clinical signs associated with thoracolumbar intervertebral disk disease (IVDD) in dogs that had decompressive laminectomy without attempted prophylactic treatment of other disk spaces. DESIGN: Retrospective study. ANIMALS: 229 dogs. PROCEDURE: Medical records of dogs that had decompressive laminectomy without prophylactic fenestration for a first episode of IVDD and were available for follow-up were reviewed. Information on 7 clinical and 8 radiographic potential risk factors were recorded. RESULTS: Clinical signs associated with recurrence of IVDD developed in 44 (19.2%) dogs. Ninety-six percent of recurrences developed within 3 years after surgery. Recurrence developed in 25% of Dachshunds and 15% of dogs of other breeds combined. Number of opacified disks was a significant risk factor for recurrence. Risk increased with number of opacified disks in an almost linear manner; each opacified disk increased risk by 1.4 times. Dogs with 5 or 6 opacified disks at the time of first surgery had a recurrence rate of 50%. CONCLUSIONS AND CLINICAL RELEVANCE: When all likely episodes of recurrence are considered and a long follow-up period is achieved, true rate of recurrence of IVDD appears to be higher than in many previous reports. Dogs with multiple opacified disks at the time of first surgery should be considered a high-risk subpopulation.     

Gastric hemorrhage in dogs given high doses of methylprednisolone sodium succinate.

OBJECTIVE: To determine whether healthy dogs given high doses of methylprednisolone sodium succinate (MPSS) develop gastrointestinal tract ulcers and hemorrhage. ANIMALS: 19 healthy male hound-type dogs. PROCEDURE: Dogs were assigned randomly to intravenously receive high doses of MPSS (30 mg/kg of body weight, initially, then 15 mg/kg 2 and 6 hours later, and, subsequently, every 6 hours for a total of 48 hours; n = 10) or an equal volume of saline (0.9% NaCl) solution (9). Gastroduodenoscopy was performed before and after treatment. Endoscopic evidence of gross hemorrhage in the cardia, fundus, antrum, and duodenum of each dog was graded from none (0) to severe (3), and a total stomach score was calculated as the sum of the regional gastric scores. Number of ulcers were recorded. The pH of gastric fluid and evidence of occult gastric and fecal blood were measured. Food retention was recorded. RESULTS: Gastric hemorrhage was evident in all dogs after MPSS administration and was severe in 9 of 10 dogs but not visible in any dog after saline treatment. Occult gastric blood was detected more commonly (9/10 vs 2/9), median gastric acidity was greater (pH 1 vs pH 3), and food was retained more commonly (7/10 vs 1/9) in the stomach of MPSS-treated dogs. CONCLUSIONS AND CLINICAL RELEVANCE: High doses of MPSS cause gastric hemorrhage in dogs. All dogs treated with high doses of MPSS should be treated with mucosal protectants or antacids to prevent gastric hemorrhage.     

Assessment of the usefulness of the fenestration method in cases of disc extrusion in the cervical and thoraco-lumbar spine in chondrodystrophic dogs

The aim of this paper was to assess the effectiveness of treatment of Type I (according to Hansen) intervertebral disc extrusion using the fenestration method. The evaluated clinical material included 37 chondrodystrophic dogs in which multiple fenestration (from 2 to 6 intervertebral spaces) was performed. Dachshunds comprised 86.5% of patients. All dogs were administered corticosteroids during the operation. A mass similar to a slightly jelly-like yogurt, cottage cheese or plaster-like consistency was extracted. In one case a post-surgical pyogenic infection of the wound occured. In two cases, a deterioration in the neurological state followed the fenestration procedure of the cervical spine. In one case of thoraco-lumbar spine fenestration, a deterioration of clinical state was found. Recovery was observed after disc extrusion from the cervical spine in 8 out of 11 dogs, from the thoraco-lumbar spine in 12 out of 14 dogs with the 2nd grade clinical signs and in 11 out of 12 dogs with the 3rd grade clinical sings. In 6 dogs, recurrence of first or second grade clinical signs occurred, but only half of them had to undergo treatment. The probability of dog recovery did not depend on the degree of symptom intensity in a statistically significant way (p=0.11) or on the duration of the disease before the surgical treatment (p=0.87).     

Functional outcome following hemilaminectomy without methylprednisolone sodium succinate for acute thoracolumbar disk disease in 51 non-ambulatory dogs

Objective: To report the functional outcome of hemilaminectomy in dogs with acute thoracolumbar intervertebral disk disease (IVDD) without the administration of a methylprednisolone sodium succinate (MPSS) protocol. Design: Prospective study. Setting: Private practice specialty hospital. Animals: Fifty‐one, client owned, non‐ambulatory dogs weighing less than 15 kg that had not been treated with MPSS. Interventions: Myelography and hemilaminectomy Measurements and main results: Fifty‐one dogs met the inclusion criteria. Before surgery, all dogs were non‐ambulatory (26 paraplegic, 25 paraparetic), and 98% were painful. Preoperative incontinence was not assessed or unknown in most cases. Ten days following surgery, 90% were ambulatory, 98% were pain free, and 82% were fully continent. By 6 weeks, 100% were ambulatory, 94% were pain free, and 86% were fully continent. By 16 weeks, 96% were pain free, and 88% were fully continent. Conclusion: Hemilaminectomy is highly successful in returning non‐ambulatory, small breed dogs to full function and in these dogs MPSS may not be a necessary adjunct to surgery.     

Idiopathic Eosinophilic Masses of the Gastrointestinal Tract in Dogs

Background: Eosinophilic inflammation of the gastrointestinal tract of dogs occurs in numerous disorders, typically resulting in diffuse intestinal thickening. Rarely, eosinophilic masses have been reported.
Objective: Describe a series of dogs with 1 or more idiopathic eosinophilic gastrointestinal masses (IEGM) to better characterize the clinical features, treatment, and prognosis.
Animals: Seven dogs with 1 or more gastrointestinal masses composed primarily of eosinophilic infiltrates for which no underlying cause was found.
Methods: Retrospective case series.
Results: Rottweilers and purebred, large breed dogs predominated. Dogs were middle-aged and typically had chronic signs of upper or lower gastrointestinal disease. Decreased appetite, vomiting, and evidence of gastrointestinal hemorrhage were present in the majority of cases. An abdominal or rectal mass was frequently noted on physical examination. Common laboratory abnormalities included peripheral eosinophilia, mature neutrophilia, hypoproteinemia, and hypocholesterolemia. The masses were histologically composed of moderate to severe eosinophilic infiltrates, which were often transmural and accompanied by fibrosis. All dogs treated with surgery alone died of complications of their disease. Treatment with corticosteroids and ivermectin improved clinical signs, caused resolution of eosinophilic infiltrates, and prolonged survival in most dogs treated medically.
Conclusions and Clinical Importance: These findings suggest that the prognosis for dogs with IEGM may be good when recognized and managed appropriately. When surgery is performed, medical treatment should also be added.     

Association between Hyperglycemia and Survival in 228 Horses with Acute Gastrointestinal Disease

Background: Glucose homeostasis is dysregulated in critically ill humans resulting in hyperglycemia and decreased survival. Hyperglycemia is common in horses presenting with abdominal crisis, and this might be associated with a worse prognosis for survival.
Objective: To determine if hyperglycemia in horses with acute abdominal disease is associated with increased odds of failure to survive to hospital discharge.
Animals: Two hundred and twenty-eight adult horses with acute gastrointestinal disease.
Methods: Observational retrospective study. Records of horses > 1 year of age presenting for treatment of colic over a 3-year period were reviewed. Data collected included age, duration of colic, glucose, heart rate, PCV, total protein, anion gap, cost of hospitalization, breed, sex, pain at admission, diagnosis, whether surgery was performed, and life status at hospital discharge. Potential risk factors for nonsurvival were screened by univariable logistic regression and the best-fitting univariable model was used as the basis for multivariable regression modeling.
Results: Mean blood glucose was 155 mg/dL (8.5 mM) with 45% of the population above the reference range; 16.7% (38 of 228) of horses had severe hyperglycemia (>195 mg/dL; 10.7 mM). Factors associated with increased odds of failure to survive included glucose, severity of pain at admission, heart rate, PCV, anion gap, and diagnosis. The best-fitting multivariable model included glucose and diagnosis, with age included as a confounding variable. The model correctly classified outcome for 92.5% of horses.
Conclusions and Clinical Importance: This study has confirmed prior reports that hyperglycemia is common in horses with colic and is associated with a worse prognosis for survival to hospital discharge.     

Pes varus correction in Dachshunds using a hybrid external fixator

Objective— To describe surgical correction of pes varus deformity in Dachshunds by acute medial opening wedge osteotomy of the distal aspect of the tibia stabilized with a hybrid external skeletal fixator (HESF), and report clinical and radiographic outcomes.
Study Design— Multicenter, retrospective clinical study.
Animals— Immature Dachshunds (n=13) with pes varus deformity.
Methods— Limb function and lameness scores were assigned before and after surgery, and correction was determined visually at surgery. Tibiotarsal joint orientation (TTJO) and medial and lateral tibial cortex lengths, measured on radiographs of deformed and normal (when available) limbs, were compared before correction and after fixator removal.
Results— Pes varus deformities (n=14) were corrected; 93% had good to excellent clinical outcome. None of the dogs had a normal preoperative gait. Mean TTJO of abnormal and normal tibiae before surgery were 29° varus (median, 28°), and 12° valgus (median, 12°). Angular correction ranged from 20° to 51° (mean, 36±8°; median, 36°). M e an TTJO after fixator removal was 7° valgus (median, 7°). Two dogs had minor transient postoperative complications whereas 3 had major complications; only 1 of which was resolved.
Conclusions— Pes varus deformity in Dachshunds can be corrected by acute medial opening wedge osteotomy of the distal aspect of the tibia stabilized by HESF. Technique modifications are needed to improve correction precision.
Clinical Relevance— Visual inspection of limb alignment during surgery resulted in good to excellent clinical outcomes; however, 91% of tibiae were under- or overcorrected (mean, 6°; median, 5°). Limb alignment should be based on evaluation of immediate postoperative TTJO measurements, not solely on intraoperative visual assessment.     

ASYMPTOMATIC RADIOGRAPHIC DISAPPEARANCE OF CALCIFIED INTER VERTEBRAL DISC MATERIAL IN THE DACHSHUND

The occurrence of asymptomatic disappearance of intervertebral disc calcification was evaluated in a radiographic prospective longitudinal study of 40 Dachshunds followed from 6 or 12 months of age to 2 years of age. Radiographic follow-up was performed at 3 to 4 years of age in 12 dogs. Disappearance of calcified disc material was observed in 9 thoracic and 1 lumbar intervertebral discs. The crude incidence rate tended to increase with age from 1 year of age. The features of the disappearing calcifications involved indicate that the phenomenon is part of the progressive degenerative process. A possible pathogenesis includes tearing of the annulus fibrosus due to the severe degeneration of the disc, followed by an inflammatory response to nuclear material and phagocytic resorption of calcified material.     

Osteological and morphometric observations on intervertebral joints in the canine pre-diaphragmatic thoracic spine (Th1-Th9)

The incidence of facet aplasia was investigated in three groups of pure-bred dogs. We examined large breeds (Rough Collies, Doberman Pinschers, Rottweilers, Bernese Mountain Dogs, German Shepherd Dogs), chondrodystrophic breeds (Dachshunds, Pekinese dogs), and small breeds (Yorkshire Terriers, Maltese dogs). Uni- or bilateral aplasia of zygapophyseal (facet) joints was exclusively found in juvenile and adult small dogs, in which the incidence of aplasia ranged from between 26% (Th1) and 63% (Th8). There was no evidence that aplasia of zygapophyseal joints increases the risk of developing intervertebral disc disease or deformative spondylosis in small breeds. By applying the findings of previous empirical studies on intervertebral disc geometry and its biomechanical behaviour on the present morphometric results, there was an indication that the intervertebral disc may well compensate for the functional loss of aplastic zygapophyseal joints in small dogs. Biomechanical factors and their potential role as inducing agents of facet aplasia in the pre-diaphragmatic thoracic spine are also discussed.     

Investigation of parameters predicting the need for diagnostic imaging beyond computed tomography in the evaluation of dogs with thoracolumbar myelopathy: Retrospective evaluation of 555 dogs

Thoracolumbar myelopathy encompasses a number of disease processes such as intervertebral disc disease, discospondylitis, trauma, congenital malformations, neoplasia, and intramedullary spinal cord disease. Compressive disc herniations are most common in dogs and require imaging procedures such as myelography, computed tomography (CT), and/or magnetic resonance imaging (MRI) to determine the need and location for decompressive surgery. The purposes of this retrospective, cross‐sectional study were to evaluate all dogs undergoing thoracolumbar CT imaging as the initial diagnostic step between 2010 and 2015 and determine whether any of the imaging characteristics could be used to predict the need for additional imaging in the form of myelography, CT myelography, and/or MRI. A total of 555 dogs were identified in this time frame which underwent CT imaging for myelopathy of the thoracolumbar region. Various parameters including age, gender, sexual status, breed, chronicity, site of lesion, time of study, and contrast administration were evaluated. Findings indicated that 7.6% of dogs needed additional imaging after CT. Dachshunds were less likely to need additional imaging (P = 0.0111) as were patients scanned during normal business hours (P = 0.0075). Increasing age of the patient increased the likelihood of additional imaging (P = 0.0107). Dogs which did not have additional imaging performed were 21.89 times more likely to require surgery than those which did have additional imaging (P < 0.0001). Findings supported the use of CT as a first‐line imaging modality for dogs presenting with thoracolumbar myelopathy.     

Diagnosis of lumbosacral intervertebral disc disease and protrusion in a horse using ultrasonographic evaluation and computed tomography

This case report describes the clinical presentation, diagnostic imaging modalities, treatment and post mortem evaluation of lumbosacral intervertebral disc protrusion in a mature Quarter Horse gelding 10 days after initial signs were noted. Grade 3 hindlimb ataxia, conscious proprioceptive deficits, urinary and faecal incontinence were present, which did not improve with anti‐inflammatories, antimicrobial therapy, corticosteroids, antioxidant therapy, cold‐laser therapy or electroacupuncture. Imaging modalities utilised ante mortem were computed radiography, transcutaneous and transrectal ultrasonography. Transrectal ultrasonography yielded findings highly suggestive of lumbosacral intervertebral disc protrusion and due to the lack of improvement and a poor prognosis, the horse was humanely subjected to euthanasia. Post mortem computed tomography, necropsy and histopathological evaluation confirmed lumbosacral intervertebral disc disease and protrusion into the spinal canal with subsequent impingement of the spinal nerve roots. Lumbosacral intervertebral disc protrusion as a clinical disease in the horse has not been previously described and should be included as a differential diagnosis in cases with acute hindlimb ataxia, proprioceptive deficits, and urinary and faecal incontinence.     

Intervertebral disc disease in Dachshunds radiographically screened for intervertebral disc calcifications

Background

Intervertebral disc disease (IDD) is a very common neurological disease, Dachshunds being the breed most often affected. In this breed, IDD has a hereditary background and is associated with intervertebral disc calcification (IDC), an indicator of severe intervertebral disc degeneration. In Finland, spinal radiography is used, when screening for IDC before breeding Dachshunds. We evaluated the association between IDC and IDD in Finnish Dachshunds radiographically screened for IDC.A questionnaire was sent to owners of 193 radiographically screened Dachshunds aged at least ten years. Clinical signs indicative of IDD were compared with IDC grade (grade 0 = no calcifications, grade 1 = 1 – 2 calcifications, grade 2 = 3 – 4 calcifications and grade 3 = 5 or more calcifications) and with age at the time of the radiographic examination. The diagnosis of IDD was confirmed by a veterinarian.

Results

IDD was common in the study population with 31% of dogs being affected. IDD and IDC were clearly connected (P < 0.001); IDD was rare in dogs with no calcifications (grade 0) and common in dogs with severe IDC (grade 3). The IDC grade was strongly positively associated with frequency of back pain periods (P < 0.001), and dogs with IDC grade 3 had frequent periods of pain. Reluctance to jump onto a sofa had a strong positive association with back pain. No association existed between age of the dog at the time of the radiographic examination and clinical signs indicative of IDD.

Conclusions

Radiographically detected IDC and IDD are common in Finnish Dachshunds and are strongly associated with one another. Spinal radiography is an appropriate screening tool for breeders attempting to diminish IDC and IDD in Dachshunds. A breeding program that screens dogs and selects against IDC can be expected to reduce the occurrence of IDD in future. Twenty-four to 48 months of age is a suitable age for screening.

Electronic supplementary material

The online version of this article (doi:10.1186/s13028-014-0089-4) contains supplementary material, which is available to authorized users.     

Perianesthetic morbidity and mortality in dogs undergoing cervical and thoracolumbar spinal surgery

ObjectiveTo evaluate and compare perioperative morbidity and mortality in dogs undergoing cervical and thoracolumbar spinal surgery.Study designProspective case series.Animals157 dogs undergoing cervical or thoracolumbar spinal surgery.MethodsData were collected sequentially on canine cases presented from the Neurology Section of the North Carolina State University Veterinary Teaching Hospital for anesthesia and surgery for cervical spinal cord disease. Simultaneously, data were collected on all thoracolumbar spinal surgery cases during the same time period. Data included signalment, drugs administered, surgical approach, disease process, cardiac arrhythmias during anesthesia, and outcome.ResultsData were collected from 164 surgical events in 157 dogs. There were 52 cervical approaches; four dorsal and 48 ventral. All thoracolumbar surgeries were approached dorsolaterally. Four dogs 4/52 (7.6%) undergoing a cervical approach did not survive to discharge. Two dogs (2/8; 25%) underwent atlanto-axial (AA) stabilization and suffered cardiovascular arrest and two dogs (2/38; 5.2%) undergoing cervical ventral slot procedures were euthanized following anesthesia and surgery due to signs of aspiration pneumonia. All dogs undergoing thoracolumbar surgery survived until discharge (112/112). Mortality in dogs undergoing cervical spinal surgery was greater compared with dogs undergoing thoracolumbar spinal surgery (p = 0.009), however, in dogs undergoing decompressive disc surgery, intraoperative death rates were not different between dogs undergoing a cervical compared with thoracolumbar approaches (p = 0.32) nor was there a significant difference in overall mortality (p = 0.07).Conclusion and clinical relevanceOverall, dogs undergoing cervical spinal surgery were less likely to survive until discharge compared with dogs undergoing thoracolumbar spinal surgery. Mortality in dogs undergoing cervical intervertebral disc decompression surgery was no different than for dogs undergoing thoracolumbar intervertebral disc decompression surgery. However, dogs undergoing cervical intervertebral disc decompression surgery should be considered at risk for aspiration pneumonia.     

Subarachnoid abscess as a complication of discospondylitis in a dog

A three-year-old German shepherd dog was presented with a history of acute neck pain. A diagnosis of acute discospondylitis involving two intervertebral disc spaces was made. The dog initially responded to conservative treatment over an eight-week period and then suddenly deteriorated. Spinal cord compression was evident on cervical myelography. At autopsy, a subarachnoid abscess was present at the intervertebral disc space between the sixth and seventh cervical vertebrae.