| dc.description.abstract | Background: Modic changes (MC) are signal intensity changes in the vertebral endplates visible on Magnetic Resonance Imaging (MRI). In humans there is a strong association between the presence of MC’s and lower back pain. MC’s are also visible on MR images of dogs, however the association between the presence of these changes and lower back pain in the dog is yet undetermined.
The purpose of this study was to investigate whether there is a correlation between MC’s and lower back pain in dogs.
Material and Methods: For this retrospective research 340 lumbar MRI’s were analyzed from dogs referred for MRI December 2013 to November 2016 to the Department of Clinical Sciences of Companion Animals, Utrecht during University. These MR images were evaluated for the presence, type and severity of MC’s and for the presence and grade of disc degeneration and herniation. A scoring sheet was used to determine whether the patients were experiencing low back pain at the time the MRI was performed.
Results: tatistical analysis with Pearson’s Chi MC’s are present in the canine spine with a prevalence of 77% and sSquared Test showed a significant predilection site on the lumbosacral junction (p<0.001) in comparison to other lumbar segments. Type 3 changes are the most found changes in the canine spine. Logistic regression analysis showed that protrusion of the intervertebral disc (IVD) is a risk factor for the presence of MC’s on L7-S1 (<25% protrusion with OR of 2.436 [95% CI 1.339-4.433, p=0.004], >25%<50% protrusion with OR of 3.611 [95% CI 1.813-7.192, p<0.001], >50% protrusion with OR of 14.711 [95% CI 5.364-40.344, p<0.001] and extrusion with OR of 17.105 [95% CI 3.788-77.249, p<0.001]).
Predictors of disc degeneration are age (OR 1.336, 95% CI 1.199-1.488, p<0.001), Chondrodystrophic breeds (OR 6.229, 95% CI 2.921-13.286, p<0.001), >50% protrusion of the IVD (OR 5.591, 95% CI 2.039-15.327, p=0.001) and MC type 1 (OR 9.856, 95% CI 1.956-49.659, p=0.006).
No significant correlation is found between low back pain and the presence of MC’s or other radiographic findings.
Conclusion: Modic change type 3 is a common finding on MR images of dogs with a predilection site on L7-S1. This study found that MC’s are positively associated with protrusion and extrusion of the adjacent IVD. Disc degeneration has positive associations with age, chondrodystrophia, protrusion of the IVD and MC type 1. So far no correlations have been found between the presence of MC’s and low back pain in the dog. | |
