Hemilaminectomy, Diverticular Marsupialization, and Vertebral Stabilization for Thoracolumbar Spinal Arachnoid Diverticula in Five Dogs

ABSTRACT Medical records (2004–2016) of five dogs with a thoracolumbar spinal arachnoid diverticula (SAD) that was diagnosed with stress myelography in four dogs and magnetic resonance imaging in three, and who had hemilaminectomy, diverticular marsupialization, and vertebral stabilization, were reviewed. Data on previous treatment, pre- and postoperative neurologic status, diagnostic findings, surgical techniques, and outcomes was retrieved. Follow-up clinical and radiographic evaluations were performed immediately; ∼1, 2, and 6 mo postoperatively; and at annual follow-up examinations. The stress myelography demonstrated spinal cord dynamic compression in three of four dogs and change in size or shape of the SAD in all four. Two dogs who had SAD recurrences 4 and 13 mo after previous surgical dural fenestration, and one dog with no previous SAD treatment demonstrated long-term neurological improvement after vertebral stabilization (49, 77, and 126 mo). In two other dogs, recurrence of clinical signs was observed at the follow-up (8 and 12 mo). This case series suggested that repetitive spinal cord injury from the dynamic lesion appears to be one potential cause of thoracolumbar SADs. In cases with dynamic lesions confirmed by stress myelography, vertebral stabilization with conventional techniques is indicated to prevent SAD recurrence.

Surgical Management of Thoracolumbar Myelopathies in Pug Dogs with Concurrent Articular Facet Dysplasia

Objectives The aim of this article is to present the outcome of vertebral stabilization using pins and polymethylmethacrylate in isolation or with concurrent spinal cord decompression for thoracolumbar myelopathies in Pug dogs with associated caudal articular process dysplasia. Materials and Methods Retrospective case review of 14 Pug dogs with thoracolumbar myelopathy and concurrent caudal articular process dysplasia identified with magnetic resonance imaging and computed tomography. Pug dogs were graded based on the Texas Spinal Cord Injury Scale and clinical follow-up was performed immediately after surgery, at the discharge and at during the postoperative period (median 5 months). Postoperative computed tomography was performed immediately post-surgical intervention in all cases and a variable postoperative time (6 weeks or 6 months). Follow-up with telephone interview with owners was performed at a median time of 12 months postoperatively. Results Median age of presentation was 8.5 years. In 10/14 cases, neurological improvement was observed, while urinary/faecal incontinence resolved in only two of seven affected cases. Other congenital vertebral malformations were identified in 9/14 cases. Clinical Significance In our population of Pug dogs with thoracolumbar myelopathy and concurrent caudal articular process dysplasia, vertebral stabilization in isolation or with concurrent spinal cord decompression appeared to result in a favourable clinical outcome in the majority of patients. This technique may be favourable for myelopathies with a reportedly poor surgical outcome in this breed.

Ventral Stabilization of a T2-T3 Vertebral Luxation via Median Sternotomy in a Dog

An 8-year-old neutered male miniature Poodle presented for evaluation of a suspected T3-L3 lesion with cervical component following vehicular trauma. Magnetic resonance imaging and computed tomography revealed a T2-T3 luxation with right displacement of T3. A T2 caudal endplate fracture was present as well as multifocal noncompressive bulges of cervical intervertebral discs. Conservative management failed and ventral stabilization of C7-T4 was performed via a median sternotomy. Paired String-of-Pearls plates were placed on the ventral aspect of vertebrae. Eight weeks postoperatively, the dog was ambulatory with moderate pelvic limb paraparesis. A luxation of T2-T3 is uncommon in small animals and surgical stabilization is poorly described in literature. This case report demonstrates the use of a ventral approach to cranial thoracic vertebral stabilization with a successful outcome.

Clinical Evaluation of Percutaneous Vertebroplasty in a Patient with Paraplegia and Immobilization Syndrome: A Case Report

We will discuss a potential role of percutaneous vertebroplasty (PVP) in the management of a patient with immobilization syndrome due to paraplegia and vertebral osteoporotic fractures. While PVP is commonly used for the treatment of osteoporotic thoracolumbar vertebral compression fractures, its role in vertebral stabilization in patient with immobilization syndrome has not been reported in the literature. A 73-year-old woman affected by immobilization syndrome due to paraplegia and vertebral osteoporotic fractures was treated with PVP of vertebrae D12, L1, and L4. After PVP, the patient did not need any antalgic therapy, and there was a significant improvement regarding mobilization, performance of physiological functions, daily management of personal care, and treatment of decubitus ulcers, increasing life quality and psychological well-being.

Hemilaminectomy and vertebral stabilization for thoracolumbar intervertebral disc associated dynamic compression in 11 dogs

Summary Objective: To describe the diagnostic findings, surgical technique and outcome in dogs with thoracolumbar intervertebral disc-associated dynamic compression. Study design: Retrospective case series. Animals: Client owned dogs (n = 11). Methods: Medical records (2005–2010) of dogs with a stress myelographic diagnosis of spinal cord injury due to thoracolumbar intervertebral disc-associated dynamic compression with inconclusive compression in the neutral myelographic views that had hemilaminectomy and vertebral stabilization were reviewed. Data on pre- and postoperative neurologic status, diagnostic findings, surgical techniques and outcomes were retrieved. Follow-up clinical and radiographic evaluations were performed immediately, and at approximately one, two, and six months postoperatively as well as at annual followup examinations. Results: The stress myelography demonstrated distinct ventral dynamic compression due to bulging of the disc and additional dorsal compression due to infolding of the ligamentum flavum in some cases. The median percentage of post-stress reduction in spinal cord height on the lateral view was 18.0% (9.8-27.2%). All dogs recovered after surgery and at follow-up examinations were still ambulatory (median: 45 months, range: 7 to 94 months). Conclusions and clinical relevance: Thoracolumbar intervertebral disc degeneration may result in disc-associated dynamic compression. Stress myelography was an effective means of diagnosing this condition and hemilaminectomy with vertebral stabilization was an effective treatment resulting in longterm neurological improvement in all dogs.

Directed Injection of Vertebroplastic Cement at the Site of a Lytic Metastatic Lesion Restores Strength With Minimum Injection Volume

Metastatic disease in the thoracolumbar spine represents a large and growing problem. These metastases can lead to pain, pathologic fracture, and neurologic compromise. Over the last two decades, the utilization of polymethylmethacrylate (PMMA) for percutaneous vertebral stabilization has increased. Most of the biomechanical and outcomes data addresses the use of vertebroplasty and kyphoplasty procedures for osteoporotic fractures [1,2]. Use of these procedures for metastatic disease enjoys a long clinical history, but the outcomes and complications are notably higher than in osteoporosis [3,4]. Newer formulations of PMMA used in advanced systems such as the Perimeter System (DePuy, Raynham, MA) may allow carefully controlled, anatomically directed PMMA application with far greater control. However, The relative benefits of these newer, proprietary systems have not been demonstrated. Proposed benefits of direct void reconstruction, as opposed to anterior vertebral body fill include: tumor lysis, decreased risk of later tumor growth with canal compromise, the ability to use less total PMMA, decreased impact on adjacent segment mechanics, and therefore, a decreased adjacent segment fracture risk. This study was conducted to examine and compare the biomechanical effectiveness of the cement augmentation (vertebroplasty) and directed PMMA injection using the Perimeter system.