Abstract: Background: Clinical characteristics of cervical hydrated nucleus pulposus extrusion (HNPE) in canines compared to other causes of cervical myelopathy are not well described.
Hypothesis/Objectives: HNPE dogs will have specific clinical characteristics allowing differentiation compared to intervertebral disc extrusion (IVDE) and fibrocartilaginous embolism (FCE).
Animals: 268 client-owned dogs (46 HNPE, 192 IVDE, 30 FCE) presented to a neurology service from 2010-2022.
Methods: Retrospective study. Patients diagnosed with HNPE, IVDE, or FCE on MRI were included. Age, weight, pain score, Modified Frankel Score, and lateralizing signs were included for logistic regression. Central cord signs, disc space involvement, and ventilation requirement were evaluated separately.
Results: In a multinomial model (HNPE vs IVDE, and HNPE vs FCE), decreasing age modestly decreased the odds of HNPE (OR:0.98 and 0.96), decreasing weight modestly increased the odds of HNPE (OR:1.03 and 1.01). Increasing pain score increased the odds of IVDE (vs HNPE; OR:2.05); while decreasing pain score increased the odds of FCE (vs HNPE; OR:0.42). Lateralization dramatically increased the odds of either IVDE or FCE (vs HNPE; OR:2.3 and 7.3, respectively). 35% (16/46) of HNPE dogs had central cord signs, compared to 19% (36/192) IVDE and 13% (4/30) FCE. 70% of HNPE dogs had a lesion at C3-4 or C4-5. Ventilation was required for 9% HNPE, 1% IVDE, and 0 FCE cases.
Conclusions and clinical importance: Compared to IVDE and FCE, HNPE dogs have differences in clinical characteristics, and might be more likely to require ventilation. These differences should be considered for case management.
.jpg "Megan Lin, VMD photo")
