Objectives: To define the characteristics of optimum implantation corridors in vertebral bodies C2 to C7 and T10 to S1, using computed tomography examination.

Methods: Measurements were taken from 207 vertebrae from 35 different adult dogs.

Results: Implantation corridors of the cervical vertebrae are narrow. The width preserving the transverse hole is less than 2·5 mm in 68·6 per cent of the 86 vertebrae C2 to C6. Dorsal implantation corridors of the last four thoracic vertebrae are narrow, and major anatomical structures are very close to their emergence point. In 63 per cent of the 40 thoracic vertebrae, the right azygos vein is at a distance less than or equal to 1 mm from the vertebral body. The first six lumbar vertebrae have broader corridors. Furthermore, vascular structures are far from the emergence point. The last lumbar vertebra and the sacrum have a broad pedicle, which provides an alternative site for implant placement.

Clinical Significance: For the vertebrae L1 to S1, the dorsal implantation can be performed. For the cervical vertebrae, the risk of laceration of the vertebral artery is high. For the last four thoracic vertebrae, the dorsal implantation should not be used.