Thoracic Kyphosis Associated with Hemivertebra

Abstract

To radiographically assess the influence of thoracic hemivertebra on kyphosis and neurologic status in 45 dogs. Case series. French Bulldogs without neurologic signs (n = 41) and 4 dogs with compressive spinal cord disease associated with hemivertebra. Thoracic spinal radiographs were divided into 3 groups: 1 = dogs with no hemivertebra, 2 = dogs with hemivertebra but no associated neurologic signs, and 3 = dogs with hemivertebra associated with clinical signs. Vertebral canal height, vertebral column angle, and the step between 2 adjacent vertebrae were measured in each group. Vertebral canal height was not significantly different in the 3 groups; however, mean vertebral column angle was significantly (P < .001) different between groups 1 (178°) and 2 (169°), and group 3 (133°). Median cranial step was significantly different between groups (P < .001): 0 mm (group 1), 0.3 mm (group 2), 3 mm (group 3). Vertebral canal height does not differ between normal dogs and dogs with thoracic hemivertebra. There is an important association between neurologic signs and kyphosis and subluxation. Vertebral realignment without vertebral canal opening could lead to spinal cord decompression in dogs affected by thoracic hemivertebra.