A retrospective study of dystocia-related vertebral fractures in neonatal calves.

Forty-seven cases of neonatal vertebral fractures/luxations occurred in a 21 year period (1967-1987). All of the fractures were located between the 11th thoracic vertebra and the fourth lumbar vertebra; 77% occurred at the thoracolumbar junction. All but one case was associated with a forced extraction, either unspecified (53%), mechanical (28%), or manual (17%).A weak calf or continuous recumbency since birth was the major clinical sign. Hemorrhage around the kidneys, adrenal glands, and in perivertebral muscles was a consistent necropsy finding and a useful indicator that a thoracolumbar fracture was present. In addition to the vertebral fracture, the prominent necropsy findings were subdural and epidural hemorrhage, myelomalacia, spinal cord compression or severed spinal cord, and fractured ribs. All of the calves died or were euthanized without regaining locomotory function.