Spinal Cord Swelling as a Myelographic Indicator of Prognosis: A Retrospective Study in Dogs With Intervertebral Disc Disease and Loss of Deep Pain Perception

Abstract

The association of myelographic spinal cord swelling with neurological outcome was examined in 46 dogs with intervertebral disc disease and absence of deep pain perception (DPP). Spinal cord swelling was measured by calculating a ratio of the length of the loss of the myelographic dye column to the length of the second lumbar vertebra (L2). A positive neurological outcome was defined as return of voluntary motor function. A cut-off value for swelling:L2 of 5.0 was established by the creation of a receiver operator characteristic curve. Using a swelling:L2 ratio of 5.0 as a cutoff for indication of neurological recovery yielded a sensitivity of 74% and a specificity of 61%. Overall neurological recovery rate was 43%. Dogs with spinal cord swelling:L2 ratios less than 5.0 had a recovery rate of 61%, whereas dogs with a ratio greater than or equal to 5.0 had a recovery rate of 26%. Evaluation of these data by chi square analysis confirmed that a ratio less than 5.0 was associated with a positive outcome, and a ratio greater than or equal to 5.0 was associated with a negative outcome, (P < .05). Although other factors, such as duration of neurological signs, affect neurological outcome in dogs with no DPP, evaluation of myelographic spinal cord swelling can assist in establishing a prognosis.

Prognostic Factors Associated with Recovery of Ambulation and Urinary Continence in Dogs with Acute Lumbosacral Spinal Cord Injury

“…Our data support the consensus from previous studies indicating that presence or absence of CPP is the most important prognostic factor for functional recovery from SCI 5, 6, 12, 13, 14, 15. Indeed, we found that loss of CPP seems to be an indicator for poor recovery in dogs with L4‐S3 SCI (1/13 dogs recovered within 3 weeks, and 3/11 had a long‐term successful outcome).…”

Acquisition of Involuntary Spinal Locomotion (Spinal Walking) in Dogs with Irreversible Thoracolumbar Spinal Cord Lesion: 81 Dogs

“…Considering the difficulty of objectively establishing the extent of the spinal cord damage, it is generally accepted to use the absence of pain perception as the most important indirect sign to asses complete functional spinal cord transection 1, 5. Absence of pain perception is classically associated with a severe to poor prognosis for functional recovery of voluntary locomotion 2, 6, 7, 8, 9. A recent study on paraplegic TL dogs with absent pain perception due to IVDE did not identify prognostic factors for any of the investigated variables, including age, corticosteroid administration, early surgical treatment, and severity of compression 10.…”

Recuperação funcional de cães paraplégicos com doença do disco intervertebral toracolombar sem percepção à dor profunda submetidos ao tratamento cirúrgico: 15 casos (2006-2010)

“…Outros estudos demonstraram uma variação de 25% a 100% de recuperação considerada satisfatória em cães paraplégicos e sem PDP (Duval et al 1996, Laitinen & Puerto 1998, Scott & Mckee 1999, Olby et al 2003, Kazakos et al 2005, Arias et al 2007, Festugatto et al 2008. No estudo de Arias et al (2007), os oito cães sem PDP voltaram a caminhar, sendo cinco sem seqüelas neurológica e três com ataxia proprioceptiva.…”

“…No estudo de Arias et al (2007), os oito cães sem PDP voltaram a caminhar, sendo cinco sem seqüelas neurológica e três com ataxia proprioceptiva. Várias são as justiϐicativas para explicar as diferenças nas taxas de recuperação (Duval et al 1996, Laitinen & Puerto, 1998, porém, neste estudo, o baixo número de casos e a diϐiculdade em determinar e estimar a duração da perda da PDP contribuiu para o resultado. Kazakos et al (2005) questionaram o valor prognóstico da ausência da PDP em cães com DDIV toracolombar devido à interpretação subjetiva e veriϐica-ram que a velocidade da perda dos movimentos voluntá-rios é mais precisa e o prognóstico é mais favorável para aqueles com perda progressiva da função motora.…”

“…Vários trabalhos vêm mostrando os resultados satisfatórios do tratamento cirúrgico em cães paraplégicos sem PDP (Anderson et al 1991, Mckee 1992, Duval et al 1996, Scott 1997, Scott & Mckee 1999, Macias et al 2002, Olby et al 2003, Kazakos et al 2005, Laitinen & Puerto 2005. No Brasil, porém, poucos estudos são encontrados em cães com DDIV toracolombar nessas condições e submetidos ao tratamento cirúrgico.…”