Prevalence and clinical features of thoracolumbar intervertebral disc‐associated epidural hemorrhage in dogs

Abstract

Background: Intervertebral disc-associated epidural hemorrhage (EH) in dogs is a poorly understood neurological condition.Objective: To compare the clinical presentation, magnetic resonance imaging (MRI) changes, and clinical outcome of dogs with acute thoracolumbar intervertebral disc herniation (TL-IVDH) with and without EH. Animals: One hundred sixty client-owned dogs that underwent MRI and hemilaminectomy for acute TL-IVDH at a private practice in Colorado, including 63 dogs with EH and 97 dogs without EH. Methods: Retrospective review of medical record data from 160 dogs presenting sequentially to a single practice with acute TL-IVDH that underwent MRI and hemilaminectomy surgery. Results: Sixty-three of 160 (39%) dogs had confirmed EH. French Bulldogs were significantly overrepresented (23/63; odds ratio [OR]: 4.1; 95% confidence interval [CI]:1.8-9.0; P < .001) of the EH cases. Dogs with EH were more likely to present with clinical signs less than 48 hours than were dogs without EH (24-48 vs 48-72 hours; OR: 2.4; 95% CI: 1.2-4.6; P = .02) and were more likely to be nonambulatory on presentation (OR: 2.1; 95% CI: 1.0-4.1; P = .04). Dogs with EH were more likely to have <50% cross-sectional spinal cord compression than dogs without EH (OR: 2.3 vs. 0.4; 95% CI: 1.2-4.4 and 0.2-0.9, respectively), longer longitudinal spinal cord compression (3 spaces vs 1 space, P < .001), and greater intrinsic spinal cord change (grade 3/severe vs grade 1/mild; P < .001) based on MRI. The location of the intervertebral disc herniation in French Bulldogs with EH was more likely to be thoracolumbar

Prevalence, clinical features, and outcome of intervertebral disc extrusion associated with extensive epidural hemorrhage in a population of French Bulldogs compared to Dachshunds

“…The presence of DEEH was associated with the presence of T2W spinal cord hyperintensity in this study, suggesting that extensive haemorrhage leads not only to mechanical spinal cord compression but also to cytotoxic effect due to red blood cell breakdown products starting the inflammatory cascade. The overall result could enhance spinal cord damage, as proposed in other studies [9].…”

“…Intervertebral disc extrusion and DEEH are well-described pathological conditions in veterinary medicine [ 5 , 6 , 9 , 10 , 16 , 26 , 28 ]. However, to the best of our knowledge, the prevalence of DEEH and its clinical features in specific breeds has not been evaluated.…”

“…A very recent study evaluated the prevalence and clinical features of thoraco-lumbar intervertebral disc extrusion associated epidural hemorrhage in dogs. Among the breeds evaluated, it was found the highest prevalence in French Bulldogs (66%); Dachshunds were less likely to present epidural haemorrhage associated with intervertebral disc extrusion (10%) [ 9 ].…”

“…Intervertebral disc extrusion associated with extensive epidural hemorrhage (DEEH) is a pathological condition well documented in veterinary medicine [ 9 , 11 , 20 , 25 , 26 , 27 , 28 ]. Hemorrhage at the time of intervertebral disc extrusion is probably caused by a rupture of the ventral internal vertebral venous plexus, which lies over the intervertebral disc space on the floor of the vertebral canal and is covered by epidural fat [ 7 ].…”

“…To the best of our knowledge, the prevalence, clinical features, and outcome of DEEH have not been evaluated in chondrodystrophic breeds in veterinary medicine: French Bulldogs and Dachshunds are predisposed to developing intervertebral disc extrusion and have a high allele frequency for 12-FGF4 retrogene, implicated in intervertebral disc degeneration [ 4 , 22 ]. French Bulldogs are also demonstrated to be likely to developing intervertebral disc extrusion associated with epidural hemorrhage (prevalence of 66%) [ 9 ] . We hypothesized that the prevalence of DEEH is higher in French Bulldogs compared to Dachshunds.…”