# Computed Tomography Prevalence of Cervicothoracic Endplate Junction Alterations in Dogs

## TL;DR

This study examines CT scans of dogs to find how often changes in spinal endplate junctions occur, which could lead to disc degeneration and back issues.

## Contribution

The study reports the prevalence of cervicothoracic endplate junction alterations in dogs using computed tomography.

## Key findings

- Endplate junction alterations were found in 1.16% of intervertebral disc spaces in dogs.
- C6–C7 and C7–T1 disc spaces were most commonly affected by these alterations.
- The overall prevalence of these alterations was low in the studied dog population.

## Abstract

The intervertebral disc acts as a cushion for the spine and as a flexible transition between the non-flexible vertebral bodies. The intervertebral disc attaches to the vertebral body at the endplates, and alterations in the endplate junction could predispose to spinal degeneration and intervertebral disc weakness, potentially leading to the presence of pain and/or herniation. Computed tomographic studies of the cervicothoracic spine of dogs were reassessed to evaluate the presence of endplate junction alterations that could potentially lead to intervertebral disc degeneration. Abnormalities in the annular–vertebral junction were only visualized in 1.16% of evaluated intervertebral disc spaces.

Spinal degenerative changes can predispose back pain and neurological deficits in dogs. In humans and veterinary patients, the endplate junction has been proposed as an alternative site of failure in addition to damage of the annulus fibrosus, leading to intervertebral disc herniation. Some alterations lead to contour abnormalities with or without regional mineralizations and can be classified as Endplate Junction Failure (EPJF), osteochondrosis (with or without fragmentation), or spondylarthritis. The objective of this retrospective study was to describe the prevalence of endplate junction alterations (EPJA) on CT in dogs at the cervicothoracic junction and classify alterations based on recent presumed EPJF grading. Computed tomographic scans of 315 dogs that included the cervicothoracic (C6–T2) spine for a variety of reasons obtained between January 2020 and December 2022 were assessed for the presence of alterations, location and type. Other spinal abnormalities were also described. A total of 945 intervertebral disc spaces were evaluated, and EPJA were found in 11 intervertebral disc spaces (1.16%). C6–C7 and C7–T1 intervertebral disc spaces were equally affected (five cases each), with only one case affecting T1–T2. In conclusion, cervicothoracic endplate alterations were anecdotically observed on CT in a population of dogs.