The adverse influence of diminished spinal cord blood flow has been well documented. There is increased skeletal blood flow in Paget's disease of bone, with a corresponding reduction in the size of the anterior spinal artery. Use of salmon calcitonin results in rapid reduction in the bone perfusion. The recovery of cord function following calcitonin therapy in patients with paraplegia due to Paget's disease of the vertebral column is likely to be due to enhanced spinal cord perfusion.