Thoracic spine - lateral canine veterinary X-ray positioning guide Positioning In lateral recumbency Ensure spine parallel to cassette/table top Use sponges under sternum to prevent rotation Pull thoracic limbs cranially Centre over T6-T7 Collimate to include entire thoracic spine, including spinous processes Ensure L/R marker in primary beam. What to look for Ensure the entire spinous processes are seen, and the spine is not rotated. Top tips Foam pads under the sternum reduce rotation; also padding under the lumbar spine can often help straighten out the thoracic spine better.