Degenerative Lumbosacral Stenosis Research Articles

Perioperative epidural catheter analgesia as a component of a multimodal analgesic approach in a dog with thoracic hemivertebrae and kyphosis undergoing thoracic vertebral stabilisation

AbstractA 4‐year‐old, male, neutered French bulldog weighing 13.5 kg presented with urinary and faecal incontinence, progressive, non‐painful paraparesis and pelvic limb proprioceptive ataxia. Magnetic resonance imaging revealed a T12 constrictive myelopathy in association with multiple thoracic vertebral malformations, and mildly impinging thoracic intervertebral disc protrusions. Additionally, there was a sacral axial defect and degenerative lumbosacral stenosis. Surgical treatment comprised bilateral dorsal vertebral stabilisation of T9–T13. This case report summarises the peri‐anaesthetic management, which included an ‘in‐plane’ ultrasound‐guided placement of an epidural catheter at the level of L3–L4 and advancement cranially to T12 as a component of a multimodal analgesic regimen. Following the cessation of postoperative epidural bupivacaine administration, the patient remained comfortable without requiring rescue analgesia, and was discharged within 24 hours of surgery. At the latest recheck 5 months after surgery, the dog's neurological status remained static. This technique and application remain unexplored in existing veterinary literature.

Surgical Treatment Options for Degenerative Lumbosacral Spinal Stenosis

Degenerative spinal stenosis is the most common type of degenerative and dystrophic spine disease. The clinical picture of stenosis, which may include axial pain syndrome, leg pain, intermittent claudication syndrome, weakness and loss of sensitivity in the legs, and impaired pelvic functions, can significantly worsen patients’ quality of life and reduce their ability to work and lead an active lifestyle.
 Degenerative spinal stenosis mostly affects the elderly. Therapeutic and neurological communities have stereotypes about spine surgery being too traumatic and invasive, and, therefore, they believe that their use should be contraindicated to and limited in elderly patients. However, surgeons are increasingly giving preference to minimally invasive interventions with high efficacy and safety together with a low risk of complications.
 We aimed at reviewing current treatment methods for degenerative lumbosacral spinal stenosis with an emphasis on surgical treatment methods.

Comparing clinical outcomes of dogs suffering from degenerative lumbosacral stenosis upon surgical or nonsurgical treatment

PICO question In dogs suffering from degenerative lumbosacral stenosis (DLSS), is surgical treatment more effective than nonsurgical therapy in reducing lumbosacral pain and neurological dysfunction in the long-term? Clinical bottom line Category of research Treatment. Number and type of study designs reviewed Two papers were critically reviewed. They were prospective and retrospective studies. Strength of evidence Weak. Outcomes reported Besides the two studies, there are no other studies currently available that directly compare long-term clinical outcome of patients that have undergone nonsurgical and surgical treatment respectively. In the study comparing clinical outcome of nonsurgical treatment by epidural steroid injection (ESI) and surgical treatment of degenerative lumbosacral stenosis, dogs were classified into clinical severity groups ranging from mild to moderate to severe. Mild cases demonstrated degenerative lumbosacral stenosis (DLSS) compatible clinical signs such as lumbosacral pain, reluctance to climb stairs / jump / raise up, lameness and muscle atrophy but no neurological deficits. Moderate cases presented DLSS compatible clinical signs in combination with neurological deficits such as reduced flexor withdrawal, proprioceptive deficits and nerve root signature. Severe cases demonstrated DLSS compatible clinical signs with more severe neurological deficits such as tail paresis and absent perineal reflex. Clinical outcomes were considered complete if clinical signs had resolved at follow-up consultations, partial if there was substantial but incomplete improvement in clinical signs and failed if the dog did not improve or deteriorated further. Improvements in patient condition were measured in terms of clinical outcome grading which is in relation to the initial clinical severity group assigned to each dog. Improvement after single dose of ESI was seen in 27/32 dogs, with 17/22 (after accounting for four dogs whose owners have refused further treatment, five dogs lost to follow-up after re-check as well as one dog whose owners have opted for repeated ESI instillations) relapsing within 6 months. All 17 of these dogs that suffered a relapse after single ESI subsequently underwent surgical treatment and demonstrated improvement in clinical signs, with a complete response seen in eight dogs and a partial response seen in nine dogs. In the study comparing clinical outcome of conservative treatment of exercise restriction with phenylbutazone administration and surgical treatment of degenerative lumbosacral stenosis, outcomes were classified as good in dogs that regained preoperative activity levels; acceptable in dogs with persistent abnormality or requiring continued medication though otherwise active, and poor in all other cases. Out of 16 dogs treated surgically, 11 were treated by dorsal lumbosacral laminectomy and excision of the dorsal portion of the lumbosacral disc, while the other five had additional unilateral facetectomy to decompress the seventh lumbar nerve. Out of the 11 dogs treated with dorsal lumbosacral laminectomy and excision of the dorsal portion of the lumbosacral disc, 6/11 (54.5%) of dogs were deemed to have a good outcome, while 3/11 (27.3%) of dogs were deemed to have an acceptable outcome. Out of the five dogs treated with dorsal lumbosacral laminectomy and excision of the dorsal portion of the lumbosacral disc with additional unilateral facetectomy, 3/5 (60%) of dogs were deemed to have an acceptable outcome. The outcome of conservative treatment was deemed good in 8/16 (50%) of dogs in the conservative treatment group. Conclusion There is evidence suggesting that both nonsurgical and surgical treatments can improve clinical outcomes and reduce lower back pain and neurological deficits. However, based on the current limited literature, it cannot be ascertained whether surgical treatments are more effective than nonsurgical treatments in improving long-term clinical outcomes and vice versa. In the study that tested the efficacy of epidural steroid injection, only a single dose of steroids was given in this study, making it a potential reason for the high rate of relapse following nonsurgical treatment. For surgical treatment of DLSS, the type of surgical procedure chosen would also depend on the part of the lumbosacral region which fails and leads to compression. In conclusion, randomised controlled trials that compare different forms of nonsurgical treatment with surgical treatment for dogs with DLSS caused by different underlying factors need to be conducted to properly address the PICO question. How to apply this evidence in practice The application of evidence into practice should take into account multiple factors, not limited to: individual clinical expertise, patient’s circumstances and owners’ values, country, location or clinic where you work, the individual case in front of you, the availability of therapies and resources. Knowledge Summaries are a resource to help reinforce or inform decision making. They do not override the responsibility or judgement of the practitioner to do what is best for the animal in their care.

Suspected ischaemic myelopathy following lumbosacral epidural steroid injection in a dog

AbstractAn 11‐year‐old, female, spayed crossbreed with an 18‐month history of degenerative lumbosacral stenosis presented for routine epidural steroid injection 4 months after previous injection. Following epidural steroid injection, the dog developed severe left hindlimb paresis with reduced to absent sciatic reflexes, delayed conscious proprioception in the limb, absence of anal tone and lower motor neuron urinary incontinence. Magnetic resonance imaging was performed, which demonstrated findings consistent with an ischaemic myelopathy. The dog's left hindlimb paresis improved on cage rest; however, urinary incontinence remained. The dog was subsequently euthanased due to quality‐of‐life concerns. This is the first published report of suspected ischaemic myelopathy developing in a dog after epidural steroid injection.

Postoperative outcomes of combined surgery comprising dorsal laminectomy, transarticular screws, pedicle screws and polymethylmethacrylate for dorsal fixation in 21 dogs with degenerative lumbosacral stenosis.

To retrospectively review the efficacy of combined surgery comprising dorsal laminectomy and dorsal fixation using screws and polymethylmethacrylate as treatment for dogs with degenerative lumbosacral stenosis (DLSS). 21 client owned dogs diagnosed with DLSS and treated surgically. Based on clinical records, signalments, clinical signs, findings from orthopedic and neurological examinations, imaging findings, and postoperative complications were evaluated at the following time points: preoperatively, postoperatively, and 3, 6, 12, 24, and 36 months after surgery. In all 21 cases, clinical signs were alleviated, proprioceptive deficits were improved from 3 months after surgery, and no recurrence of clinical signs was observed during the observation period. Minor complications were observed in 6 cases (28.6%), including implant failure in 2 (9.5%), delayed healing of surgical wounds in 2 (9.5%), seroma in 1 (4.8%), and swelling of the affected area in 1 (4.8%). There was no case with major complications. Combined surgery comprising dorsal laminectomy and dorsal fixation using screws and polymethylmethacrylate is a useful treatment that can improve long-term clinical signs in dogs with DLSS.

Dynamics of cerebrospinal fluid in correction of degenerative lumbosacral stenozis during the postoperative period in dogs

Dynamics of cerebrospinal fl parameters in postoperative period during correction of degenerative lumbosacral stenosis in dogs is an important diagnostic aspect that allows monitoring changes in the state of animals after surgery. An accurate analysis of cerebrospinal fl id provides a wide range of information about the patients neurological health. The assessment should consist of macroscopic, quantitative and microscopic analyses. Сell count is the most important and potentially sensitive indicator of disease. The aim of this study was to determine changes in the cerebrospinal fluid during the postoperative period in the correction of degenerative lumbosacral stenosis. In the study, there were 9 dogs of various breeds, aged from 2 to 8 years (experimental group), the indicators of cerebrospinal fluid and peripheral blood of 3 healthy outbred dogs obtained as a result of medical examination at the age of up to 5 years were used as a control. Surgical intervention was carried out according to the B.P. Meij, N. Bergknut, which consists in dorsal access to the L7-S 1 vertebral arches, soft tissue dissection, dissection of the dorsal ligament, formation of channels in the cranial articular processes of S 1, L7. From each animal, three liquorograms were taken for examination three times on days 1-3 after surgery, on days 12-15 and 27-30 after surgery. The study of cerebrospinal fluid was performed within 30 minutes after taking. As a result of the data obtained, it was found that the cellular composition of the liquor of dogs in the postoperative period of correction of lumbosacral stenosis was within the physiological norm, erythrocytes in the cerebrospinal fluid were not detected. The number of nucleated cells in operated dogs was the highest on days 1-3 after surgery. On the 12th-15th day after the operation, cytosis in the experimental and control groups of animals was 1.27 cells/l more. On days 27-30 after surgery, cytosis in dogs in the experimental group was lower by 0.45 cells/l compared to the control. Analysis of cerebrospinal fluid can help in the diagnostic assessment of the condition of animals in the postoperative period. However, it should be borne in mind that results are rarely specific to any particular condition and should be interpreted in the light of clinical and additional diagnostic findings.

ОЦЕНКА ХИРУРГИЧЕСКОЙ КОРРЕКЦИИ ДЕГЕНЕРАТИВНОГО ПОЯСНИЧНО-КРЕСТЦОВОГО СТЕНОЗА НА ОСНОВЕ ЭРИТРОЦИТАРНОЙ СОСТАВЛЯЮЩЕЙ У СОБАК

Degenerative lumbosacral stenosis is a common cause of lumbosacral disease in dogs of medium to large breeds. However, decompressive surgery is considered the primary technique for reducing cauda equina and nerve root compression in dogs with degenerative lumbosacral stenosis. The study of the dynamics of the erythrocyte component remains the main indicator of control over the postoperative period during surgical interventions in dogs and deserves their careful analysis. The aim of this study was to evaluate changes in the structural characteristics of erythrocytes during the postoperative period. In this article, an assessment was made of changes in hematological parameters and erythrocyte morphology during the postoperative period. Conducting surgical neurological intervention in the lumbosacral region, with strict observance of aseptic and antiseptic requirements and precise implementation of the method of surgical access and reception, ensures the physiological functioning of the erythrocyte link without causing destructive processes during the postoperative period and the presented surgical method can serve as the basis for performing neurological surgical interventions.

Platelet-Rich Plasma for the Treatment of Degenerative Lumbosacral Stenosis: A Study with Retired Working Dogs.

Simple SummaryThe incidence of degenerative lumbosacral stenosis in dogs has been increasing in the last few years, mainly due to longer life expectancy. Given that degenerative lumbosacral stenosis is due to multifactorial causes, there is no consensus regarding the best treatment strategy. The aim of this study was to subjectively and objectively assess the efficacy of a series of epidural infiltrations of a platelet-rich plasma derivative. Fourteen retired working dogs with this syndrome were infiltrated, and clinical and force platform data were recorded. The results showed a significant clinical and gait improvement during the 90-day period. This treatment strategy seems to be a good alternative to other medical treatments, given that the autologous product is effective and considered innocuous.Traditionally, canine degenerative lumbosacral stenosis (DLS) has been defined as a multifactorial syndrome characterized by lumbosacral pain triggered by the compression of the nerve rootlets of the cauda equina. There is still no consensus on the treatment of this condition, probably because there are a plethora of possible causes. In addition to compression, inflammation is a very important factor in the physiopathology of the disorder. Platelet-rich plasma (PRP) consists of an increased concentration of autologous platelets suspended in a small amount of plasma. Platelets are a source of several growth factors. Growth factors were shown to help in wound healing and biological processes, such as chemotaxis, neovascularization and synthesis of extracellular matrix, and growth factors were used to improve soft tissue healing and bone regeneration. PRP also facilitates the restoration of the structural integrity of the affected anatomy. Fourteen dogs diagnosed with DLS were treated with three epidural injections of PRP on days 0, 15 and 45. All dogs showed clinical improvement 3 months after the initial treatment. Gait was also objectively assessed by means of the use of force platform analysis before and after treatment, showing significant improvement. The results show that PRP may provide a good alternative to other nonsurgical treatments, such as prednisolone epidural injection.

Case Report: Successful Therapy of Spontaneously Occurring Canine Degenerative Lumbosacral Stenosis Using Autologous Adipose Tissue-Derived Mesenchymal Stem Cells

The management of degenerative lumbosacral stenosis (DLSS) in dogs usually requires aggressive, costly surgical treatments that may themselves present complications, while do not fully resolve the symptoms of the disease. In this study, the dog diagnosed with severe DLSS, with hind limb paresis, was treated using a new and least invasive treatment. Cultured autologous adipose tissue-derived mesenchymal stem cells (AT-MSCs) were injected bilaterally at the level of L7-S1, in the vicinity of the external aperture of the intervertebral foramen of DLSS patient. In the previously described treatments of spontaneous intervertebral disc degeneration in dogs, intradiscal injections of MSCs did not lead to positive effects. Here, we report a marked improvement in clinical outcome measures related to the ability of a dog to walk and trot, which were expressed by a numeric rating scale based on a veterinary assessment questionnaire. The improved status persisted throughout the observed time course of 4.5 years after the AT-MSC transplantation. To the best of our knowledge, this is the first case of successful therapy, with long-term positive effect, of spontaneously occurring canine DLSS using presented treatment that, we believe, represents a contribution to current knowledge in this field and may shape both animal and human DLSS treatment options.

Three-Dimensional Kinematics of the Pelvis and Caudal Lumbar Spine in German Shepherd Dogs.

Lumbosacral vertebral motion is thought to be a factor in the development of degenerative lumbosacral stenosis in German shepherd dogs. So far, few studies exist describing natural canine lumbosacral movement in vivo. Therefore, this investigation aims to achieve a detailed in vivo analysis of bone movement of the lumbosacral region to gain a better understanding of the origin of degenerative lumbosacral stenosis using three-dimensional non-invasive in vivo analysis of canine pelvic and caudal lumbar motion (at L6 and L7). Biplanar cineradiography of the pelvis and caudal lumbar spine of four clinically sound German shepherd dogs at a walk and at a trot on a treadmill was recorded. Pelvic and intervertebral motion was virtually reconstructed and analyzed with scientific rotoscoping. The use of this technique made possible non-invasive measurement of physiological vertebral motion in dogs with high accuracy. Furthermore, the gait patterns of the dogs revealed a wide variation both between individual steps and between dogs. Pelvic motion showed a common basic pattern throughout the stride cycle. Motion at L6 and L7, except for sagittal rotation at a trot, was largely asynchronous with the stride cycle. Intervertebral motion in all dogs was small with approximately 2–3° rotation and translations of approximately 1–2 mm. The predominant motion of the pelvis was axial rotation at a walk, whereas lateral rotation was predominant at a trot. L7 showed a predominance of sagittal rotation (with up to 5.1° at a trot), whereas lateral rotation was the main component of the movement at L6 (about 2.3° in both gaits). During trotting, a coupling of various motions was detected: axial rotation of L7 and the pelvis was inverse and was coupled with craniocaudal translation of L7. In addition, a certain degree of compensation of abnormal pelvic movements during walking and trotting by the caudal lumbar spine was evident.

Accuracy of Placement of Pedicle Screws in the Lumbosacral Region of Dogs Using 3D-Printed Patient-Specific Drill Guides.

The aim of this study was to report the accuracy of pedicle screw placement using three-dimensional (3D)-printed, patient-specific drill guides in the lumbosacral region of dogs. This was a retrospective study. Thirty-two pedicle screws were placed in five dogs. Medical records were reviewed between November 2015 and November 2018 for dogs showing clinical signs associated with cauda equina syndrome. Inclusion criteria included preoperative magnetic resonance imaging, pre- and postoperative computed tomography (CT) and dorsal stabilization, with pedicle screws placed using 3D-printed, patient-specific drill guides and polymethylmethacrylate. Screw placement was evaluated for medial or lateral breaching on postoperative CT. Five dogs met the inclusion criteria. Four had degenerative lumbosacral stenosis and one had discospondylitis. All dogs had failed medical management prior to surgery. Of 32 bicortical pedicle screws placed, 30 were fully contained inside the pedicle and 2 were partially breaching the vertebral canal (less than one-third of the screw diameter). Postoperative CT revealed good alignment of L7-S1 in all planes. This technique enabled an accurate and safe placement of pedicle screws in the lumbosacral region of dogs with lumbosacral disease. Three-dimensional, printed patient-specific drill guides are a safe and effective method of placing pedicle screws in dogs with lumbosacral disease.

Lumbosacral Fusion Using Instrumented Cage Distraction–Fixation in a Dog with Degenerative Lumbosacral Stenosis

AbstractThis study aimed to assess the long-term outcome and intervertebral fusion following surgical distraction and stabilization using an intervertebral cage and pedicle screw and rod fixation (PSRF) in a dog with severe degenerative lumbosacral stenosis (DLSS).Degenerative lumbosacral stenosis is a common disorder in large breed dogs and has a multifactorial origin. Surgical treatment by dorsal laminectomy and discectomy results in decompression of neural structures, but when distraction–fixation is applied, the ultimate goal is vertebral fusion. A 4-year-old male neutered Leonberger, presented with DLSS and pre-existent chronic discospondylitis, was treated by dorsal laminectomy, partial discectomy, curettage of the end plates, distraction with an intervertebral spacer (SynCage), and PSRF. At 26 months after surgery, the Helsinki pain score and neurological Griffith score were improved; however, the dog passed away shortly thereafter due to an unrelated disorder. The lumbosacral segment became available for computed tomography (CT), micro-CT and histopathology. On CT, bone volume through the largest hole of the cage was 91.0% and for compact bone 76.1%. Micro-CT and histopathology revealed vertebral fusion. Distraction–fixation using an intervertebral spacer and PSRF was well-accepted in this dog with severe DLSS, and the dog had a good clinical outcome with long-term follow-up. CT, micro-CT and histopathology showed evidence of vertebral fusion.

Dynamic MRI is reliable for evaluation of the lumbosacral spine in healthy dogs.

Magnetic resonance imaging (MRI) is commonly used to diagnose degenerative lumbosacral stenosis; however, studies show limited correlation between imaging and clinical signs. The purpose of this prospective observer agreement study was to use dynamic MRI of the lumbosacral (LS) spine of healthy dogs to determine reliable reference ranges. Twenty-two healthy large breed dogs were prospectively enrolled. MRI of the LS spine was performed in T2-weighted, T1-weighted, and T2-weighted SPACE sequences in neutral, flexed, and extended positions. Four observers performed image analyses. Measurements included LS angle, vertebral canal height and area, and LS foraminal areas. Ordinal categorical assessment of loss of fat signal in the foramina, LS compression, intervertebral disc (IVD) degeneration, spondylosis, and IVD protrusion was also performed. The majority of values were significantly larger in flexion versus neutral position, and significantly smaller in extension versus neutral position (P<.05). Subclinical compression and IVD protrusion was noted in a neutral position in 45% and 55% of dogs and in an extended position in 85% and 73% of dogs, respectively. Interobserver agreement was strong (intracluster correlation coefficient [ICC]>.5) except for the L7:LS vertebral canal area ratio (ICC ≤ .03). Intraobserver agreement was high (rho>.5) for all measurements except for the mid-L6:LS vertebral canal height ratio (rho=.38). There was poor interobserver agreement for loss of fat signal in the foramina and evidence of compression. This study provides the groundwork for future studies using dynamic MRI to evaluate dogs with signs of clinical LS disease.

Evaluation of L7-S1 nerve root pathology with low-field MRI in dogs with lumbosacral foraminal stenosis.

To describe low-field MRI findings associated with lumbosacral foraminal stenosis and radiculopathy and correlate these with clinical signs. Retrospective study. Client-owned dogs (n = 240) that underwent a clinical examination and standardized MRI protocol of the lumbosacral junction. Medical records of dogs with degenerative lumbosacral stenosis with neurological clinical evaluation and MRI of the lumbosacral junction were used to describe imaging pathologies and relate them to clinical status. In total, 480 L7 neuroforamina were evaluated. A loss of foraminal fat signal was identified in 364 of 480 neuroforamina of which 87.9% (n=320) showed also concurrent nerve root changes. Magnetic resonance imaging features of L7 radiculopathy included nerve root enlargement and hyperintensity to surrounding connective tissue in dorsal oblique gradient echo short time inversion recovery sequences and specific changes in shape, size, or position of the nerve root in transverse T1-weighted sequences. Radiculopathy was noted as a consequence of either circumferential (entrapment) or focal (impingement) foraminal stenosis. Lateral vertebral spondylotic and intervertebral facet joint changes were the most common underlying spinal and neuroforaminal pathologies. Clinical signs were present in the ipsilateral hind leg in 85% (n = 65) of dogs with unilateral lumbosacral imaging findings. A loss of foraminal fat signal was likely to be associated with L7 radiculopathy and foraminal stenosis. Unilateral lesions were generally associated with clinical signs on the ipsilateral limb. Loss of foraminal fat signal revealed by low-field MRI should prompt the assessment of concurrent radiculopathy and underlying stenosis, and in coherence with clinical findings, when is combined with clinical findings, improves the diagnosis of lumbosacral foraminal stenosis.

A critical appraisal of the literature exploring the surgical treatment of degenerative lumbosacral stenosis in dogs

Objective: To critically appraise the literature exploring the surgical treatment of degenerative lumbosacral stenosis in dogs.&#x0D; Background: Several surgical procedures to treat degenerative lumbosacral stenosis (DLSS) in the dog have been reported, however, definitive criteria for surgical technique preference are currently lacking (1).&#x0D; Evidentiary value and methods: A critical appraisal tool that examined the conduct and reporting of studies on the results of surgical treatment of DLSS was designed and, after a systematic search and screening of the literature, a critical appraisal was performed in 20 papers.&#x0D; Results: Results showed that 18/20 studies included did not clearly report inclusion and exclusion criteria and in 14/20 it was unclear whether consecutive inclusion of participants was applied. 19/20 studies reported age, breed, and sex of the participants, and 13/20 did not report duration and prevalence of clinical signs. In 13/20 studies, it was considered that the condition was not measured in a standard and reliable way. Objective outcome measures were used in 7/20 studies.&#x0D; Conclusion and application: The results demonstrate that there is room for improvement in the conduct and reporting quality of case series so that rigorous data can be generated and analysed, to inform research design, guide clinical practice, and improve veterinary healthcare delivery.&#x0D; &#x0D;

Single dose epidural methylprednisolone as a treatment and predictor of outcome following subsequent decompressive surgery in degenerative lumbosacral stenosis with foraminal stenosis

Alternative treatments to surgery in canine degenerative lumbosacral stenosis (DLSS) remain limited and reliable predictors of outcome are lacking. The aims of this clinical trial were threefold: to assess the usefulness of single epidural steroid injection (ESI) in DLSS, to compare the outcomes of ESI and decompressive surgery, and evaluate ESI as a predictor of outcome following decompressive surgery. Dogs diagnosed with DLSS were prospectively recruited and administered an ESI. If clinical signs persisted or relapsed, decompressive surgery was recommended. Follow-up was obtained.Thirty-two dogs underwent ESI with 17 having subsequent surgery. Improvement after ESI was seen in 27/32 dogs (84.4%), with 17/22 (77.2%) relapsing within 6 months (n = 15/17 relapsing within 2 months). Five dogs failed to respond to ESI and another five (15.6%) presented a persistent post-ESI favourable response (mean follow-up time, 9.4 months). Post-surgical improvement occurred in all dogs. Outcome appeared more favourable following surgical decompression, with a trend towards reduced pain, increased mobility, and greater quality of life score. This study was unable to demonstrate that ESI could predict surgical outcome. ESI was confirmed as an effective treatment in most but not all cases, leading to transient alleviation of clinical signs for longer than previously reported. ESI provided a complete and apparently long-term sustained resolution of clinical signs in a subset of dogs. Despite this, there was indication that surgical decompression can lead to a more favourable outcome. Epidural steroid injection has a role in the management of DLSS dogs, particularly when surgery is not an option.

The effects of foraminotomy and intervertebral distraction on the volume of the lumbosacral intervertebral neurovascular foramen: An ex vivo study

Degenerative lumbosacral stenosis in dogs frequently involves L7-S1 foraminal stenosis and L7 nerve root compression. Surgical techniques to decompress the L7 nerve root include foraminotomy and intervertebral distraction. The objective of this study was to compare the effect of foraminotomy and intervertebral distraction on the total, cranial, and caudal compartmental volumes of the L7-S1 intervertebral neurovascular foramen (NF). CT images were obtained from eight canine lumbosacral (L5-CD1) specimens in the following sequential conditions: native spine (1), after dorsal laminectomy and partial discectomy of L7-S1 (2), after L7-S1 foraminotomy (3), after distraction with an interbody cage between L7 and S1 (4), after cage distraction stabilized with pedicle screw-rod fixation in neutral (5) and flexed position (6). The volume of the complete NF and its cranial and caudal subcompartments were calculated using the CT images and statistically compared between conditions. P < 0.05 was considered statistically significant.The volume of the complete NF was significantly increased after foraminotomy (mean ± standard deviation (146.8 ± 26.5%, P < 0.01) and after distraction (Condition 4, 121.0 ± 19.1%; Condition 5, 116.6 ± 29.3 %; Condition 6, 119.0 ± 21.8 %; P = 0.01) with no difference between the distraction conditions. Foraminotomy induced a significantly larger increase in total NF volume compared to distraction. Foraminotomy, but not distraction, induced a significant increase in volume of the cranial subcompartment (158.2 ± 33.2 %; P < 0.01). Foraminotomy is more effective in increasing the foraminal volume and especially the cranial subcompartment, which is where the L7 nerve root traverses the NF. Hence, foraminotomy may be more effective in decompressing the L7 nerve root.

Canine Degenerative Lumbosacral Stenosis: Prevalence, Impact And Management Strategies.

Canine degenerative lumbosacral stenosis (DLSS) is a syndrome of low back pain with or without neurologic dysfunction associated with compression of the cauda equina. Most commonly occurring in medium- to large-breed dogs of middle to older age, German shepherd and working dogs are predisposed. Diagnosis is based on a combination of clinical signs, advanced imaging and ruling out other differential diagnoses. The volume of the intervertebral foramina at the lumbosacral junction is naturally reduced on extension but degenerative changes lead to a more marked reduction that can impinge the L7 nerve roots. Evidence is lacking on which to base decision-making for treatment of dogs with DLSS. However, surgical intervention may be indicated in dogs that do not respond to conservative management, or for dogs in which there is a requirement to work that prevents lifestyle adjustments. Improvements in electrodiagnosis and novel intra-discal treatments may improve the management of DLSS in the future.

CT measures of lumbosacral paraspinal muscle size are not correlated with CT measures of lumbosacral stability in military working Labrador Retrievers.

Management of degenerative lumbosacral stenosis in military working dogs more frequently utilizes core conditioning exercise programs. Future research on the effectiveness of these programs may benefit from an improved understanding of relationships between paraspinal muscle size and lumbosacral stability. The aim of this retrospective, secondary analysis, cross-sectional study was to test the following hypotheses related to CT measures: (a) transverse paraspinal muscle area ratios differ between hip flexion and extension, (b) lumbosacral angle and lumbosacral range of motion differ by lumbosacral angle measurement technique, and (c) transverse paraspinal muscle area ratios are correlated with CT measures of lumbosacral stability (parasagittal and parasagittal oblique foraminal area changes) regardless of hip position and with lumbosacral range of motion within each hip position. Lumbosacral CT scans in hip flexion and extension were retrieved from a previous prospective study of military working Labrador Retrievers. A single observer performed triplicate measurements of transverse paraspinal muscle area ratios, parasagittal foraminal area, and parasagittal oblique foraminal area for each hip position and another observer independently performed triplicate measurements of lumbosacral angle and lumbosacral range of motion at L7-S1 using two published techniques. Thirty-nine dogs were analyzed and significant differences were identified between hip flexion and extension for all mean transverse paraspinal muscle area ratio values (P≤.05). Mean lumbosacral angles also significantly differed between the published techniques in both hip flexion and extension. When comparing mean lumbosacral range of motion values, one of the published techniques produced significantly smaller values. No significant correlation was found between transverse paraspinal muscle area ratios and parasagittal foraminal area changes, parasagittal oblique foraminal area changes, or lumbosacral range of motion. These results should be considered when designing studies using these CT measures in military working dogs.

Clinical findings in degenerative lumbosacral stenosis in ten dogs—A pilot study on the analgesic activity of tramadol and gabapentin

Degenerative lumbosacral stenosis is a relatively common multifactorial disease that affects mainly large breed or working dogs. It can cause neuropathic pain, and advanced imaging techniques are essential to achieve a final diagnosis. For improving the quality of life, when surgery is not possible, a conservative treatment is necessary. The management of pain requires early intervention and evaluation of response on an individual-patient basis. The aim of the study was to evaluate the use of tramadol for the treatment of lumbosacral pain in dogs affected by degenerative lumbosacral stenosis diagnosed by radiographs, computed tomography, and computed tomography myelography, considering gabapentin as an alternative treatment in case of unresponsiveness. Ten dogs were enrolled, and clinical findings and their severity scores were recorded; the short form of the Glasgow composite pain scale was used to assess pain scores before (8.6 ± 1.5; 7-11/20) and during treatment (after 1, 2, and 4 weeks) with oral tramadol (3 mg/Kg every 8 hours) and prednisolone (0.5 mg/Kg/die) for 4 weeks. After the first week of therapy, only half of the dogs (5/10, T-group) showed a significant improvement of Glasgow composite pain scale score; in the remaining five dogs (G-group), tramadol was changed with oral gabapentin (10 mg/Kg every 8 hours for 3 weeks), with an improvement in pain score in one week. At the end of treatment, all the dogs showed low pain scores (T-group: 2.8 ± 0.8; G-group: 1.6 ± 0.9), below the intervention level (4/20). Given the supported evidence, oral tramadol should not be relied on as a sole or, perhaps, first-line analgesic in dogs, and gabapentin might be a valid alternative option in an outpatient setting. As controlled clinical trials are still lacking in animals, further studies should be carried out to confirm the analgesic activity of gabapentin in veterinary painful conditions and to rule out eventual adverse effects related to a prolonged administration.