The spine is made up of strong bones called vertebrae. A vertebra can break just like any other bone in the body. When the vertebral body collapses, it is called a vertebral compression fracture. These fractures happen most commonly in the thoracic spine (the middle portion of the spine), particularly in the lower part. Vertebral fractures are usually caused by a condition such as osteoporosis, a very hard fall, or another type of injury.