Predictors of urinary or fecal incontinence in dogs with thoracolumbar acute non‐compressive nucleus pulposus extrusion

Abstract

Background: Urinary (UI) and fecal (FI) incontinence occur in up to 7.5% and 32% of dogs, respectively, after thoracolumbar acute noncompressive nucleus pulposus extrusion (ANNPE).Hypotheses/Objectives: To investigate clinical, diagnostic, and therapeutic predictors of UI and FI in dogs with ANNPE affecting the T3-L3 spinal cord segments.Animals: Hundred and eighty-seven dogs with T3-L3 ANNPE diagnosed based on clinical and MRI findings.Methods: Multicenter retrospective study. Data were obtained from medical records and telephone questionnaires and analyzed by logistic regression.Results: UI and FI were reported in 17 (9.1%) and 44 (23.5%) dogs, respectively. Paraplegic dogs were 3 times (95% CI = 1.25, 10.87) more likely to develop UI (P = .018) and 4 times (95% CI = 1.94, 12.56) more likely to develop FI (P = .001) compared to nonparaplegic dogs. Dogs with an intramedullary hyperintensity greater than 40% of the cross-sectional area of the spinal cord at the same level on transverse T2-weighted MRI images were 4 times more likely to develop UI (95% CI = 1.04, 21.72; P = .045) and FI (95% CI = 1.56, 10.39; P = .004) compared to dogs with smaller lesions. FI was 3 times (95% CI = 1.41, 7.93) more likely in dogs that were not treated with nonsteroidal anti-inflammatory drugs (NSAIDs) after diagnosis compared to dogs administered NSAIDs (P = .006) and 2 times (95% CI = 1.12, 5.98) more likely in dogs presented with clinical signs compatible with spinal shock compared to dogs without (P = .026).Abbreviations: ANNPE, acute non-compressive nucleus pulposus extrusion; COX2, cyclooxygenase-2; FI, fecal incontinence; LL:VL, ratio of the length of the intramedullary lesion to the length of the L2 vertebra; NSAIDs, nonsteroidal anti-inflammatory drugs;PCSAL, percentage of the cross-sectional spinal cord area occupied by the lesion; SCI, spinal cord injury; UI, urinary incontinence.

Prognostic Factors in Canine Acute Intervertebral Disc Disease

“…In ANNPE, dogs with a smaller lesion had a shorter interval to unassisted ambulation. In contrast, a percentage cross sectional area that equals or exceeds 90% of the spinal cord had a 92% chance of having an unsuccessful long-term outcome (38), and a lesion exceeding 40% of the transverse area has been associated with an increased likelihood of long-term urinary and fecal incontinence (22). However, a low-field MRI study of 21 dogs with ANNPE found no association between any MRI parameter with outcome (71).…”

“…As such, these cases are scarcely reported in the literature and it is extremely difficult to establish what their prognosis would be if managed long term. There is a recent report of three dogs with ANNPE that recovered walking, but none recovered fecal continence and 2/3 remained urinary incontinent (22). A review of the literature on FCEM revealed seven dogs in this category for which long term outcomes were available; three of the seven recovered ambulation but there is no information on their continence (24).…”

“…Spinal shock occurs much more frequently with FCEM and ANNPE due to the peracute onset of signs in these conditions (52). The prognostic significance of spinal shock has been evaluated and its presence is associated with the development of fecal incontinence in ANNPE but does not appear to affect recovery of ambulation (22,52). The prognostic significance of the Schiff Sherrington posture has not been evaluated.…”

“…High field MRI changes have been associated with outcome in dogs with ANNPE (22,38) and FCEM (39). A larger lesion on transverse images, quantified as a greater percentage cross sectional area of the spinal cord, has been considered the most useful MRI variable to predict the short-and long-term outcome of dogs with ANNPE and FCEM (22,38,39). In ANNPE, dogs with a smaller lesion had a shorter interval to unassisted ambulation.…”

Bladder and Bowel Management in Dogs With Spinal Cord Injury

“…However, this clinical trial recruited dogs with Hansen type 1 intervertebral disc herniation in which spinal shock is less common than in more severe cases, moreover, the majority had only moderately severe injuries, again making spinal shock unlikely. In another study on thoracolumbar acute non-compressive nucleus pulposus extrusion, a weak association was found between spinal shock and the odds of remaining faecally incontinent, although this likely reflects an association between spinal shock and severity of injury ( 24 ). Interestingly, bladder atony at the time of spinal shock can be improved with functional electrical stimulation of sacral nerve roots in experimental dogs ( 25 , 26 ) when delivered early in the disease process.…”