Intervertebral Disc Extrusion Research Articles

Double Cervical Adjacent Hydrated Nucleus Pulposus Extrusion (HNPE) in a Yorkshire Terrier

A 9-year-old Yorkshire terrier was brought to the emergency department for inability to maintain the correct station with acute onset. Neurological examination showed a non-ambulatory tetraparesis, spontaneous proprioceptive deficit in all limbs, and decreased flexor reflex in the forelimbs. The neurological symptoms suggested a cranial cervical spinal cord with suspicion of spinal shock. The clinical differential diagnoses included degenerative (intervertebral disc extrusion), vascular, inflammatory, or neoplastic disease. No pathological findings were evident in the hematobiochemical tests or in the radiograph examination. MRI examination of the cervical spine showed the presence of two adjacent hydrated nucleus pulposus extrusions at C3-C4 and C4-C5 tracts. Treatment included analgesic and non-steroidal anti-inflammatory therapy; movement restriction was initially necessary, followed by physiotherapy. Follow-up at 4 weeks showed complete recovery. A telephone follow-up after 3 months with the owner confirmed the absence of symptoms. This article reports the first double cervical HNPE case in a dog, adding the possibility that the disease may present in this form and the success of conservative treatment as described in the literature.

Physiotherapy in the Recovery of Paraplegic Dogs without Nociception Due to Thoracolumbar Intervertebral Disc Extrusion Treated Surgically.

Several authors have advocated for the role of physiotherapy in canine intervertebral disc extrusion, and it is routinely recommended by various veterinary neurologists. However, veterinary literature does not unanimously support the routine use of physiotherapy to ensure an increase in locomotor return in dogs with IVDE. The aim of the study was to investigate whether physiotherapy can influence the functional recovery of paraplegic dogs with loss of nociception (LN) affected by thoracolumbar IVDE (Hansen type I) and treated surgically. The animals were divided into two groups: the physiotherapy group (PG), which included those that underwent decompressive surgery and postoperative physiotherapy; and the control group (CG), which included dogs that did not undergo any physiotherapy after surgery. A total of 51 dogs were included, with 30 in the PG and 21 in the CG. The number of physiotherapy sessions ranged from 6 to 60. The rate of functional recovery in dogs within 21 days postoperatively (PO) was 10% (3/30) in the PG and 19% (4/21) in the CG. After 21 days PO, the recovery rate was 43.33% (13/30) in the PG and 61.9% (13/21) in the CG, with no significant difference observed between the groups (p = 0.258). Based on the findings of this study, it was concluded that physiotherapy in paraplegic dogs with LN due to thoracolumbar IVDE does not appear to influence functional recovery compared to the group without physiotherapy.

Spinal magnetic resonance imaging in cats: differences in clinical significance of intervertebral disk extrusion, intervertebral disk protrusion, and degenerative lumbosacral stenosis.

To determine the occurrence of degenerative changes affecting the vertebral column in cats, assess their clinical significance, and determine the occurrence in cats with intervertebral disk herniation compared to other spinal diseases. 114 client-owned cats. Hospital records were retrospectively reviewed for cats with suspected myelopathy that had undergone spinal MRI. Signalment; history; neurological examination; neurolocalization; primary diagnosis; presence, type, and location of intervertebral disk herniation; and presence and location of other degenerative spinal changes (intervertebral disk degeneration [IVDD], spondylosis deformans [SD], end plate changes, dorsal compressions [DC], and foraminal stenosis [FS]) were recorded. 70% of cats showed at least 1 spinal degenerative change. The most common change was IVDD, followed by SD and intervertebral disk protrusion (IVDP), while intervertebral disk extrusion (IVDE), end plate changes, DC, and FS were uncommon to rare. Primary complaint was attributed to a degenerative condition in 22% of cats, including 100% with IVDE, 9% with IVDP, and 43% with degenerative lumbosacral stenosis (DLSS). The occurrence of degenerative spinal changes and number of intervertebral disks affected by IVDD significantly increased with age and body weight. Age was positively correlated with the occurrence of SD and DLSS. Intervertebral disk degeneration, IVDP, SD, DC, and FS were more prevalent in the lumbosacral junction. Cats with IVDD were significantly more likely to show IVDE and IVDP. This study revealed that in a population of cats presenting for signs of myelopathy, IVDE was always responsible for the clinical presentation, DLSS was commonly considered incidental, and IVDP was infrequently related to neurological signs.

LAMINECTOMIA DORSAL E HEMILAMINECTOMIA TORÁCICAS PARA TRATAMENTO DE EXTRUSÃO DE DISCO INTERVERTEBRAL EM CANINO

Intervertebral disc disease (IVDD) is the most common disc disease in dogs. The diagnosis is based on anamnesis, patient history, neurological examination and imaging tests and the association of these data influences the choice between conservative or surgical treatment. The objective of this report is to present a case of chronic intervertebral disc extrusion, located between thoracic vertebrae, emphasizing the clinical-surgical approach, diagnosis and established therapy. An eight-year-old female Maltese canine was referred for surgical treatment after two years of conservative treatment for IVDD. For better identification of the affected intervertebral spaces, a computed tomography scan was requested and, based on the imaging results, the procedure of hemilaminectomy in vertebrae T8-T9-T10 and dorsal laminectomy in vertebrae T12-T13 was indicated. It is concluded that the association of both surgical techniques achieved multiple decompression of the affected thoracic intervertebral spaces, ensuring better quality of life for the patient.

Recovery of ambulation in small, nonbrachycephalic dogs after conservative management of acute thoracolumbar disk extrusion.

Currently, low-level evidence suggests loss of ambulation associated with acute thoracolumbar disk extrusion is best treated by decompressive spinal surgery. Conservative management can be successful, but the proportion of dogs that recover and the fate of herniated material are uncertain. Determine the proportion of nonambulatory dogs with conservatively treated acute thoracolumbar disk extrusion that recover ambulation and measure the change in spinal cord compression during the first 12 weeks after presentation. Seventy-two client-owned nonambulatory dogs with acute thoracolumbar intervertebral disk extrusion. This is a prospective cohort study. Enrolled dogs underwent magnetic resonance imaging at presentation and owners were provided with conservative management recommendations. Imaging was repeated after 12 weeks. Recovery of ambulation was defined as 10 consecutive steps without falling. Spinal cord compression was determined from the cross-sectional area of the vertebral canal and extradural compressive material at the lesion epicenter. The association between recovery and change in compression over the 12-week observational period was examined. Forty-nine of fifty-one (96%; 95% confidence interval [CI], 87%-99%) of deep pain-positive and 10/21 (48%; 95% CI, 28%-68%) of deep pain-negative dogs recovered ambulation within the 12-week period. The median time to ambulation was 11 and 25 days for deep pain-positive and -negative dogs, respectively. Reduction in spinal cord compression varied among individuals from minimal to complete and apparently was unrelated to the recovery of ambulation. A high proportion of conservatively treated dogs recovered ambulation after conservative management of acute thoracolumbar disk herniation. Recovery was not dependent on the resolution of compression.

Thoracolumbar hydrated nucleus pulposus extrusion and intervertebral disc extrusion in dogs: Comparison of clinical presentation and magnetic resonance imaging findings

Thoracolumbar hydrated nucleus pulposus extrusion (TL-HNPE) is an increasingly recognised pathology with a substantial lack of literature describing its features. The aim of this retrospective case-control study was to analyse the clinical and magnetic resonance imaging (MRI) features of dogs with TL-HNPE compared to dogs affected with thoracolumbar intervertebral disc extrusion (TL-IVDE). Data from dogs diagnosed with TL-HNPE and TL-IVDE via MRI at two referral hospitals, were retrospectively collected and compared in terms of clinical signs and MRI features. Cases diagnosed with TL-IVDE were deemed controls. The MRI features of the affected IVD space, herniated IVD material, affected overlying spinal cord and local epaxial musculature were evaluated for each group. Fifty-one cases with TL-HNPE and 105 randomly selected cases of TL-IVDE were included. Several signalment and neurological signs were identified as statistically distinct between groups in univariate analysis. Multivariate analysis identified that dogs affected with TL-HNPE were typically older, less likely to be chondrodystrophic (62.2 % vs. 91 %), more frequently experiencing a peracute onset (90.2 % vs. 61.9 %) often attributed to a suspected trauma linked with exercise (37.3 % vs. 10.5 %), being less frequently progressive (41.2 % vs. 86.5 %) and with herniated disc material less frequently lateralised (72.6 % vs. 89.5 %) than cases with TL-IVDE. MRI-identifiable intervertebral disc degeneration was found in every TL-IVDE case but only in 60 % of TL-HNPE cases. TL-HNPEs were associated to significantly less spinal cord compression and less hyperalgesia than TL-IVDE.

The use of a minimally invasive integrated endoscopic system to perform hemilaminectomies in chondrodystrophic dogs with thoracolumbar intervertebral disc extrusions.

The objective was to evaluate the use of a minimally invasive surgical (MIS) approach to perform hemilaminectomies in chondrodystrophic dogs with thoracolumbar intervertebral disc extrusions (IVDE). Additionally, we aimed to evaluate the degree of soft tissue trauma using the endoscopic procedure compared to the standard open approach. Eight client-owned dogs presented to the Colorado State University Veterinary Teaching Hospital with acute onset thoracolumbar IVDE were included in this study. This was a prospective, randomized case-series. Patients were assigned to undergo an endoscopic (group 1; n = 4) or a standard open approach (group 2; n = 4) for a hemilaminectomy. A post-operative MRI was performed in all cases. Conversion to an open approach was not necessary for any case in group 1. All cases had adequate spinal cord decompression on post-operative MRI. There was no significant difference in soft tissue changes noted on post-operative MRI between the two groups. The MIS approach to hemilaminectomies in chondrodystrophic dogs with thoracolumbar IVDE can successfully be performed to decompress the neural tissue and appears to lead to similar clinical outcomes in the early postoperative period compared to the standard open approach. Larger studies are needed to determine the potential advantages of the MIS technique compared to the standard open approach in veterinary medicine.

Dorsal laminectomy for the treatment of lateralised cervical intervertebral disc extrusions in dogs-Prognosis and complications.

Describe the complication rate, expected hospitalization time and prognosis associated with dorsal laminectomy for the treatment of lateralised cervical intervertebral disc extrusion (IVDE) in dogs. This is a single-center retrospective case series study. Databases were reviewed from 2012 to 2022 for dogs that had a dorsal laminectomy to treat a lateralised cervical IVDE. Dogs were excluded if additional surgical techniques were performed, or other comorbidities were found on MRI. Fifty two dogs were included the study. French bulldogs represented 28.8% of the cohort. Patient median age was 6 years and median weight 15 kg. Thirty-five dogs (67.3%) presented clinical signs for <3 days and almost half (44.2%) were ambulatory but presented cervical pain and neurological deficits. Median surgical time was 85 min. Minor intraoperative complications were reported in 22 (42.3%), with hypothermia being the most common. Thirteen (25%) needed revision surgery due to persistent cervical pain with (9/13) or without (4/13) neurological deficits. Re-extrusion or persistent extrusion was found in 92.3% of cases needing surgical revision. Median hospitalization time was 6 days. Forty-seven (90.4%) cases had a good outcome. Despite the relatively high rate of intraoperative complications and cases needing revision surgery, dorsal laminectomy as surgical treatment for lateralised cervical IVDE is still associated with good long-term prognosis in most of cases. Prognosis is good even when revision surgery is necessary but expected hospitalization time seems to be higher when compared to an alternative surgical technique.

Investigation of neutering status and age of neutering in female Dachshunds with thoracolumbar intervertebral disc extrusion.

To evaluate neutering status and age of neutering in female Dachshunds with thoracolumbar intervertebral disc extrusion. We hypothesised that neutered Dachshunds presented with intervertebral disc extrusion at an earlier age, with a higher grade of neurological deficits and with more extensive extrusion of disc material compared with intact females. Retrospective multi-centre study of client-owned female Dachshunds with surgically confirmed thoracolumbar intervertebral disc extrusion. Dogs were classified as early, late or not neutered (intact). Age, body condition score, duration of clinical signs before presentation, modified Frankel score at presentation, length of extruded disc material, maximum spinal cord compression and whether dogs presented for a subsequent intervertebral disc extrusion were recorded. One hundred and fifty-four dogs were included: 36 early neutered, 69 late neutered and 49 intact. No significant difference was found between early neutered, late neutered and entire female Dachshunds in any of the variables studied. In this cohort of female dogs, neuter status and age of neutering were not found to affect age at onset nor severity of thoracolumbar intervertebral disc extrusion.

Investigating the weekend effect in decompressive thoracolumbar hemilaminectomy for acute intervertebral disc extrusion: An observational cohort study of 460 cases (2018-2023).

To investigate if weekend surgery is associated with poorer outcomes in dogs with acute thoracolumbar intervertebral disc extrusion (IVDE) undergoing decompressive thoracolumbar hemilaminectomy. Retrospective observational cohort study. A total of 460 consecutive cases were reviewed, with 401 dogs undergoing weekday surgery (Cohort WD), and 59 dogs undergoing weekend surgery (Cohort WE). Medical records of a surgical referral center in the UK were reviewed. Preoperative patient demographic and clinical data, and postoperative outcome data were collected with a minimum 28-day follow-up period. Multivariable logistic regression analysis was used to model the odds of a negative outcome. Cohort WE had a higher preoperative proportion of nonambulatory dogs (p = .0115) but there were no significant differences between the nonambulatory (p = .3762) and deep-pain negative subgroups (p = .6199). Cohort WE had a higher risk of not recovering ambulation compared to Cohort WD [79.2% vs. 91.6% recovery; adjusted OR 3.010 (95% CI: 1.259-7.190); p = .0132] and had a higher risk of postoperative morbidity [32.2% vs. 17.2%; adjusted OR 2.015 (95% CI: 1.089-3.729); p = .0257]. There were no significant differences in other outcome measures between cohorts. Weekend surgery in canine decompressive thoracolumbar hemilaminectomy may be associated with poorer patient outcomes, specifically higher postoperative morbidity and a poorer rate of recovery of ambulation. This study demonstrates a weekend effect in veterinary surgery, which may be important in surgical decision-making in acute thoracolumbar IVDE. Further scrutiny of the patient's journey through the veterinary healthcare system is warranted.

Outcome of the Use of Clinical Reasoning Alone in Dogs with Acute Thoracolumbar Myelopathy and/or Pain.

Acute thoracolumbar myelopathy is a common neurological presentation in dogs. Although certain spinal conditions present with characteristic clinical pictures, managing such cases with clinical reasoning alone (i.e., without cross-sectional imaging) has never been explored. The aim of this study was to define the outcome of patients with suspected intervertebral disc extrusion (IVDE), ischaemic myelopathy (IM) or acute non-compressive nucleus pulposus extrusion (ANNPE) that were managed with clinical reasoning alone. The database of the Queen's Veterinary School Hospital (Cambridge) was searched for paraparetic or paraplegic dogs with suspected IVDE or IM/ANNPE that were initially managed medically without undergoing imaging. Clinical presentation and outcome were recorded. If cross-sectional imaging was subsequently performed, information about the final diagnosis was collected and compared with the initially suspected diagnosis. A total of 123 IVDE cases were collected: 81% had a successful outcome with no imaging performed; 16% had IVDE confirmed with imaging and successful outcome with surgery or medical management; and just 3% were found to have an alternative diagnosis or were euthanised without imaging. A total of 16 IM/ANNPE cases were collected: 94% had a successful outcome, and one dog was euthanised. Successful outcomes can be obtained by using clinical reasoning alone in most dogs with suspected IVDE or IM/ANNPE.

Prevalence, clinical presentation, and etiology of myelopathies in 224 juvenile dogs.

Intervertebral disc herniation is widely recognized as the most common cause of myelopathy in dogs older than 2 years; however, the prevalence of various causes of myelopathy in younger dogs has not been reported. To describe the prevalence, clinical presentation, and etiology of myelopathy in dogs aged 18 months or less. Secondarily, to investigate which clinical features were associated with each of the most common etiologies. Two hundred twenty-four dogs aged 18 months or less with myelopathy were included in the study. Retrospective review of clinical records from 4 referral institutions. Multivariable logistic regression analyses assessed which clinical features were associated with each diagnosis. French bulldogs (n = 51, 22.8%), pugs (n = 18, 8.0%), crossbreeds (n = 12, 5.4%), and English bulldogs (n = 11, 4.9%) were the most frequently affected breeds. Overall, 31 diagnoses were reached. The 5 most frequent diagnoses were vertebral malformation (VM; n = 42, 18.8%), spinal arachnoid diverticulum (SAD; n = 28, 12.5%), traumatic fracture of the vertebral column (n = 22, 9.8%), atlantoaxial instability (n = 18, 8.0%), and osseous-associated cervical spondylomyelopathy (n = 17, 7.6%). Intervertebral disc extrusion (IVDE) accounted for 4.5% of cases (n = 10). A final diagnosis of VM was associated with younger, screw-tailed, and pug breeds with chronic signs of T3-L3 myelopathy. SAD was associated with screw-tailed and pug breeds with nonpainful clinical signs. Intervertebral disc extrusion was associated with older, screw-tailed, and pug breeds with shorter duration of clinical signs. Prioritization of differential diagnoses for dogs presenting with signs of myelopathy when aged 18 months or less should differ to those for older dogs, with IVDE not the most common cause in the former.

Extrusão de disco intervertebral em Buldogue Francês

Também conhecida como hérnia de disco ou discopatia canina, a extrusão de disco intervertebral em cães é uma doença degenerativa crônica ou aguda, muito comumente encontrada em clínica médica de pequenos animais, em que ocorre o “extravasamento” do disco intervertebral. Essa discopatia está dividida em três tipos, conhecidas como doença de Hansen tipo I, II e III. Este trabalho tem como objetivo descrever um relato de caso de extrusão de disco intervertebral ocorrido em Bulldog Francês desde a sua chegada na clínica até a recuperação do paciente e suas características como sintomatologia, diagnóstico e tratamento. O caso foi acompanhado durante o estágio curricular obrigatório em Medicina Veterinária na clínica Focinhos e Patinhas, em Curitiba no estado do Paraná.

Spontaneous resorption of a C7–T1 intervertebral disc extrusion in a Cavalier King Charles spaniel confirmed via low‐field MRI

AbstractA 4‐year‐old, male, neutered Cavalier King Charles spaniel was referred to the neurology service with a 10‐day history of cervical hyperaesthesia. A low‐field magnetic resonance imaging scan of the cervical spine identified a large C7–T1 intervertebral disc extrusion, resulting in severe spinal cord compression. The patient was treated with conservative therapy (exercise restriction and analgesia for 4 weeks). Repeat magnetic resonance imaging of the cervical spine was performed 4 months after initial presentation, and identified spontaneous resorption of the extruded C7–T1 disc material. There are very few documented cases of spontaneously resorbed cervical intervertebral disc extrusions in canine patients following successful conservative therapy. To the authors’ knowledge, this is the first report of spontaneous resorption of an intervertebral disc extrusion at an unusual C7–T1 location confirmed via follow‐up low‐field magnetic resonance imaging following conservative therapy.

Residual volume of extruded disc material and residual spinal cord compression measured on postoperative MRI do not predict neurological outcomes in dogs following decompressive surgery for thoracolumbar intervertebral disc extrusion.

Published studies on the validity of using quantitative MRI measures of pre- and postoperative spinal cord (SC) compression as prognostic indicators for dogs undergoing surgery for intervertebral disc extrusion (IVDE) are currently limited. The aim of this retrospective analytical study was to describe the volume of postoperative residual extradural material (VREM) and the ratio of the cross-sectional area (CSA) of maximum SC compression to the CSA of SC in a compression-free intervertebral space as MRI measures of preoperative and postoperative compression (residual spinal cord compression, RSCC), and to compare these measures between the neurological outcome in a group of dogs. Inclusion criteria were dogs that underwent surgery for thoracolumbar IVDE, were imaged pre- and immediately postoperatively by MRI, and had a neurological follow-up examination 2 to 5 weeks postoperatively. Two blinded observers independently performed measurements in pre- and postoperative MRI studies. Dogs were classified into positive outcome (PO) and negative outcome (NO) groups based on follow-up neurologic examination scores. Seventeen dogs were included (12 PO, 5 NO). Interobserver agreement for MRI measurements was good to excellent (ICCs: 0.76-0.97). The prevalence of residual extradural material in postoperative MRI studies was 100%. No significant differences in mean preoperative SC compression, mean RSCC, mean SC decompression, or VREM were found between outcome groups (P=.25; P=.28; P=.91, P=.98). In conclusion, neither postoperative VREM nor RSCC could predict successful neurological outcomes.

Clinical presentation, magnetic resonance imaging findings, and outcome of 80 Dachshunds with cervical intervertebral disc extrusion.

Large clinical studies regarding cervical intervertebral disc extrusion (IVDE) in Dachshunds are lacking. This retrospective multicentric study therefore aims to describe the clinical features, magnetic resonance imaging (MRI) findings and outcomes of Dachshunds diagnosed with cervical IVDE. Medical records of Dachshunds with cervical IVDE were reviewed for signalment, onset of clinical signs, neurological examination, MRI features, treatment and outcome. Eighty Dachshunds were included in the study, mostly ambulatory (55% grade 1 and 33% grade 2) and without nerve root signature (85% of cases) on presentation. Information on coat type was available for 56% of dogs; specifically, 41% were smooth-haired, 9% were long-haired and 6% were wire-haired Dachshunds. There were 29 (36%) neutered female, 27 (34%) male entire, 15 (19%) male neutered and 9 (11%) entire female dogs. The onset of clinical signs was most often >48 h (84%). The most common intervertebral disc space affected was C2-C3 (38%) and foraminal IVDEs were reported in 14% of dogs. A foraminal IVDE was diagnosed in only 25% of dogs presented with nerve root signatures. Most dogs (77.5%) were treated surgically. In this group, a higher body condition score on presentation and a higher mean spinal cord compression ratio calculated on MRI were directly and moderately associated with a longer hospitalization time (r = 0.490 p = 0.005 and r = 0.310 p = 0.012, respectively). The recovery time was longer in dogs with an onset of clinical signs <24 h or 24-48 h compared to those with an onset of clinical signs >48 h (3.1 ± 6.5 days versus 1.6 ± 6.2, p < 0.001) in both medically and surgically treated groups. Data about the outcome was available for 83% of dogs. Eighty percent of the entire population of dogs was considered to have completely returned to normal. There was no association between the therapeutic choice (surgical versus medical management) and the outcome of the dogs included in this study.

Surface electromyography of the vastus lateralis and gluteus medius muscles in post-operative T3-L3 hemilaminectomy dogs: a prospective controlled observational study.

The objective of this study was to determine if surface electromyography (sEMG) demonstrates differences in muscle activation between normal and dogs recovering from spinal cord injury due to intervertebral disk extrusion. Two groups of client-owned small-breed chondrodysplastic-type dogs were tested. Group 1 consisted of seven ambulatory paraparetic dogs that had undergone a hemilaminectomy procedure in the T3-L3 region for intervertebral disk extrusion 1 month prior. Group 2 was made up of seven normal dogs that had no history of intervertebral disk disease or spinal surgery. Each subject walked 10 feet on a nonslip surface for at least five gait cycles for the sEMG to capture muscle activation of the vastus lateralis and gluteus medius, bilaterally. Muscle activation was quantified as the total myoelectric output area under the curve, averaged across all gait cycles. Muscle activation was significantly greater in the post-operative hemilaminectomy group (p = 0.012). There was a significant difference in muscle activation between each hindlimb in the post-operative hemilaminectomy group, but not in the normal group. The muscle activation was significantly lower on the side that underwent surgery compared to the opposite limb (p = 0.0034). Post-operative hemilaminectomy dogs have greater hindlimb muscle activation compared to normal dogs, which likely represents a lack of descending inhibition secondary to upper motor neuron syndrome. The side of surgery is correlated with decreased muscle activation. Surface EMG can be used to evaluate muscle activity in dogs recovering from spinal decompression surgery.

Estimativa de perda sanguínea transoperatória em cães submetidos a hemilaminectomia e fenestração do disco intervertebral

ABSTRACT: There are no reported estimates of normal or abnormal bleeding in dogs during the hemilaminectomy and intervertebral disc fenestration procedures (HF), and that makes it difficult to study intraoperative complications, hemostasis methods, and the impact of bleeding on surgical performance. This prospective study estimated blood loss during HF procedures in dogs with intervertebral disc extrusion (IVDE). Blood loss was quantified by weighing gauzes during the surgical procedure, in addition to measuring the aspirated blood. Total blood volume was estimated according to body weight, and blood loss as a percentage of the total blood volume. The surgeon also subjectively classified the procedures, dividing them into intraoperative difficulty due to bleeding (G1) and absence of intraoperative difficulty (G2). Thirty-two dogs that underwent HF due to IVDE were included. The median blood loss (%) of dogs submitted to HF was 3.9 ± 9.67 of the total blood volume. There was a weak correlation between blood loss and weight, age, incision size, and procedure time.

Сравнительный анализ влияния декомпрессионных методик на диапазон движения позвонков в грудопоясничном отделе позвоночного столба у собак

The work was carried out with the aim of conducting a comparative analysis of the effect of hemilaminectomy and mini-hemilaminectomy on the range of motion of the vertebrae in the thoracolumbar spine in dogs and to establish a correlation between changes in the range of motion of the vertebrae at the site of decompression and in adjacent spinal motion segments with the incidence of relapses of intervertebral disc extrusions and the emergence of a «domino effect». The research was carried out in 2023 on the basis of the Department of Veterinary Surgery of the Federal State Budgetary Educational Institution of Higher Education MGAVMiB – MBA named after K. I. Scriabin. The object of the study was sectioned material from dogs of chondrodystrophic breeds (n=5), the subject of the study was the thoracolumbar section of the spinal column Th10-S1. The range of motion of the vertebrae in each individual spinal motion segment was studied by comparing their positions in the neutral position, during flexion and during extension: in the native state – 3 samples, in the native state and after hemilaminectomy at the Th13-L1 level – 1 sample, in in the native state and after performing a mini-hemilaminectomy at the Th13-L1 level – 1 sample. At the site where the decompression technique was applied, the range of Th13-L1 vertebral motion increased by 51,66 % with hemilaminectomy and decreased by 0,76 % with mini-hemilaminectomy (the difference is statistically significant, p=0.001). In the adjacent spinal motion segment Th12– Th13, the range of vertebral motion increased by 22,25 % with hemilaminectomy and by 8,39 % with mini-hemilaminectomy (the difference is statistically significant, p=0,01). The correlation coefficient between the frequency of relapses of extrusions and changes in the range of motion of the vertebrae at the site of decompression is 0,71, which indicates a relationship between the average tightness between the analyzed indicators. The correlation coefficient for the risk of the «domino effect » and changes in the range of motion of the vertebrae in spinal motion segments adjacent to the site of decompression is 0,77, which indicates a strong correlation between the analyzed indicators.

Conservative treatment of recurrent intervertebral disc extrusions in a lionhead rabbit

ABSTRACTA 4‐year‐old lionhead rabbit with an acute onset of abnormal hindlimb gait was presented. L4–S3 neurolocalisation was determined based on clinical findings of paraparesis, bilateral proprioceptive positioning deficits, left pelvic limb hyporeflexia and discomfort during lumbar spine manipulation. The magnetic resonance imaging (MRI) revealed an intervertebral disc extrusion (IVDE) at L4–L5, with mild spinal cord compression. The condition was treated conservatively, with cage rest and non‐steroidal anti‐inflammatory drugs. The rabbit was fully normal after 1 month. Two months later, a relapse of clinical signs was observed. A new MRI study revealed a L5–L6 IVDE with mild spinal cord compression. Conservative treatment was repeated and full recovery was confirmed at 4‐month follow‐ups associated with MRI follow‐up study. To the authors' knowledge, this is the first case report of spontaneous IVDEs in a rabbit, where MRI was used to monitor the effectiveness of the conservative management of the disease in a rabbit.