Vertebral Fractures and Luxation in Dogs

Abstract

Background: Vertebral fractures and luxations (VFL) are a major cause of neurologic injury in small animals. They are most commonly associated with severe external trauma from road traffic accidents, aggression, or falls from heights. There were few studies concerning VFL, mainly on results of treatments and sequelae. This retrospective work aimed to study patients with extrinsic trauma in the spinal cord that were treated at the Neurology and Neurosurgery Service of a Higher Education Institution in Brazil from 2007 to 2018, describing main etiologies, location of lesion, degree of neurological dysfunction, treatment, and results and sequelae after surgical or conservative therapy.Materials, Methods & Results: One hundred and nine dogs of various breed and ages were included in this study. The main etiology of the spinal cord injury in these dogs were fractures and/or dislocations caused by road traffic accidents (66%), followed by interaction with other animals (5.5%). The body region most frequently affected by the lesions were the thoracolumbar segment (T3-L3) of the vertebral spine (52.3%), followed the lumbosacral segment [L4-S3] (54.8%). The degrees of the most prevalent neurological dysfunctions for each of the segments were grade V in 73.7% of the dogs with lesions between T3-L3, and grade III in 54.8% of the dogs with lesions in L4-S3. Twenty-one tutors of dogs subjected to surgery and 20 tutors of dogs that underwent clinical treatment could be contacted by phone. Statistical analysis performed on data from these patients indicated that there was no significant correlation between the motor recovery and the type of treatment instituted. However, when the degree of motor dysfunction was analyzed in conjunction with recovery, milder grades were found to be accompanied by the best recovery results.Discussion: Road traffic accidents were the most common cause of damage to the spinal cord, a finding described in other studies on extrinsic trauma. Due to the retrospective nature of this study, the analysis of the patients' motor recovery was performed using data from only 41 patients whose tutors could be reached by phone. We found that, in dogs that had satisfactory or partially satisfactory recovery, the ability to walk was restored between two and six months independent of the type of treatment (clinical or surgical). The criteria taken into account to choose the therapeutic option were degree of neurological dysfunction and/or presence of vertebral instability based on the three-compartment theory and the choice of the tutor after information on prognosis, postoperative care, possible neurological sequelae, and costs. Even though rigid external immobilization is indicated for the conservative treatment of VFL, in this study, all dogs subjected to clinical treatment were kept in cages without the use of external immobilization. Rigid immobilization causes discomfort to the patient, as well as complications during use. Loss of deep pain sensation (nociception) may occur immediately after acute injury, and it may be recovered after stabilization. In some cases, patients may experience urinary and/or fecal incontinence. Urinary and/or fecal incontinence was the main sequela reported by tutors, and was the main reason for euthanasia of surviving patients. We believe that further studies on this subject are necessary in order to gather information that can be used to provide better assistance for future patients affected by medullary trauma due to extrinsic factors.