The thoracic spine consists of 12 thoracic vertebrae (spinal bones). The ribs, which contain the lungs have direct connections to each vertebra. Movement in the thoracic spine is limited secondary to the ribs but is still necessary in order for the trunk to fully move in all directions.
The lumbar spine consists of 5 vertebrae (spinal bones). Each vertebra can move slightly independently of each other to allow for full range of motion of the lumbar spine. Motion in the lumbar spine allows for the head and shoulders to be placed in space.
The cervical spine consists of 7 cervical vertebrae. The function of the cervical vertebrae is to support the head and place the head in space. Each vertebra (spinal bone) has the ability to move slightly independently of each other during movement. If there are restrictions at a particular level, the result will be a loss of motion in the neck.